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sailorchic34
21-07-2012, 16:56
So here I was floating in the California delta, and I decided to check my prop zinc. I have one of those cone zincs that go on the end of the prop shaft.

So I dove and looked / felt and what do you know, No zinc. To make matters worst no screw that holds the zinc on either.

Now I hate not being able to do all the boat chores, and paying a diver to change the zinc is, well, I'd rather find a way to do it myself. After a few dives I learned that this girl does not work well underwater, that whole lack of air thingy really gets to me.

So being an engineer and blonde, I started thinking out of the box again. So not a good thing sometimes.

On my boat I have a really large sea strainer. Well Large for my dinky little diesel. Something like 1-1/2” size which is 4” in diameter and 12” high in brass and glass construction. Its connected to the seacock with a 2” diameter copper standpipe, which places the top close the the water line.

So I take the cover off, and pull the basket out. Wow, the Size C prop cone zinc easily fits within the basket strainer and leaves room all around. Nice So I drilled out the zinc shaft hole to match the 1/4” copper rod the holds the cover of the strainer down. I slid the zinc inside the basket, and its a really tight friction fit on the brass rod. Cool.

Then I got some #12 wire out and a few terminal ends to fit the ¼" rod. I attach the wire to the rod between the cap and wing nut and attach the other end to the aft engine mount. Just to make sure, I measure continuity between the prop shaft and wire at the engine mount and at the copper standpipe. Neet... zero ohms. We have continuity..Life is good.

Oh I'll probably upsize the wire to the strainer, but it will be a week or so before I hit a dock / location where I can get some.

As we all know, its rather important that the zinc be electrically connected to the prop shaft. Normally the zinc is mechanically connected on the prop shaft, but that's way too messy for this girl anyway.. Plus the cone zincs have a nasty habit of falling off, when the mount hole gets bigger from zinc loss. So annoying.

I'm thinking that based on the engineering text I read that the blonde zinc replacement might just work fine. The zinc is located inside the basket strainer so any little bits of zinc that break off will be trapped in the basket

So now I have an easy way, in theory anyway to check and replace my prop zinc without getting wet. I'm going to check it over the next few weeks to make sure its hum sacrificing itself.

Now I know there will be a few guys here who will say this will not work. Its Cruisers Forum after all. But I'm just going to give it a try and see what happens. The engineer in me says this will work and the blonde says hey, hair and makeup are good to go. Sort of a blonde win win...

Jd1
21-07-2012, 17:16
Color me confused ....
Sure you got a zinc floating in salt water but are you thinking that you have perfect connectivity from the zinc to the engine out the driveshaft (through a coupler) and into the prop ? What about the path through the water back to the zinc ?

I think there is more blondness than engineering in that solution ....

Therapy
21-07-2012, 17:26
That sound OK I guess but somewhere I read that the zinc has to be in close proximity to the prop itself. Physical proximity. Not just electrically by ohm meter. I don't know where I read it though.

Good luck. I hope the test does not cost you a prop.

fstbttms
21-07-2012, 17:38
Jeezus- all to save the cost of a diver for 15 minutes? :rolleyes:

BTW- the longer the electrical path between the anode and the item (theoretically) being protected, the less protection is provided. And that's assuming (as previously mentioned) that you have good electrical contact between the zinc, shaft & prop. Reinventing the wheel rarely results in a better (or even adequate) solution.

barnakiel
21-07-2012, 18:14
On our ship there is no anode on the prop. There is one on the shaft. This one can be replaced without lifting the boat but it is easier in a calm anchorage on a calm day.

Maybe there is some space on your prop shaft where you could place an anode too?

Just guessing.

b.

sailorchic34
21-07-2012, 18:45
My shaft extends all of 1/4" from the hull to the back of the prop. So no room for a shaft zinc. There's barely enough space behind the prop to get the zinc on between it and the rudder. It's a very tight aperture prop opening.

My basis is anodes for underground pipelines. Where there is wire bonded from the anode to the pipe protecting hundred's or thousands of feet of pipe line My shaft is all of 48" long. The wire from the rear transmission mount to the sea strainer is less then 24".

BTW The zinc in the sea strainer is less then 24" physically from the prop.

Measured ohms from the front of the shaft ( I have a Vdrive) to the sea strainer is 0.00 ohms. Based on the science it should work.

As far as the diver goes. We'll I'm not at a dock, but on the hook. So its a bit more then 15 minutes for a diver to get to me. I'll be at a dock probably in a week or so. I plan on checking the zinc over the next two weeks. If it works I'll keep it. If there is no measureable loss on the zinc, Then I'll get a diver to replace it. Just no diver around where I'm at....

fstbttms
21-07-2012, 18:51
How long do you plan to keep the boat in the Delta? Something else to consider- zinc anodes are not really suitable for freshwater or brackish environments. Zero depletion in two weeks may merely mean that your anode should be aluminum or magnesium, not zinc.

sabray
21-07-2012, 18:57
Not sure what the screw is that's missing. I'm a guy so need pictures. Usually it's a collar that gets around the shaft. Then their are zincs that thread onto the shaft on threads that are also. Holding the prop in place. Are you saying there is no thread left to attach a cone. Is something eating up the zinc stray current etc... Replacing the zinc is good but what is going in that caused the failure. Don't degenerate yourself by playing girl and put down men by categorically thinking we can't be helpful. Your bright with your solution.why the proper install failed is something to look at.

fstbttms
21-07-2012, 19:05
Not sure what the screw is that's missing. I'm a guy so need pictures.
http://www.fotolode.com/images/fstbttms/Hull-cleaning/zincprop.jpg

why the proper install failed is something to look at.
What makes you think there was a failure? Anodes are supposed to deplete and go away. That's how they work.

sabray
21-07-2012, 19:12
Cause usually there is something left of the anode.To loose the whole kit suggests something isn't right. Bad install or stray current. Come on man you know this.

fstbttms
21-07-2012, 19:15
To loose the whole kit suggests something isn't right.
No it doesn't. It means that the zinc depleted to the point that the screw wasn't under tension anymore and backed out.

sailorchic34
21-07-2012, 19:17
Well I am sitting in fresh water, so Magnesium would be better, though all I have is zinc. Zinc will work, better then aluminum though not quite as good as magnesium.

Though I do move around a bit and make it back to the central bay too now and then.

Well It has been about a year since the last zinc replacement. The problem with the cone type zincs that mount to the end of the prop shaft is they tend to loosen around the single screw that holds them in. Then they fall off usually while moving.

Plus I'm missing the screw that attaches it, which is the second time that has happened too.

I don't expect much resistance loss in the 1.125 shaft and I measure ohms from the center of the shaft to the sea-strainer and copper standpipe. I do think a thicker wire will help too as we're dealing with millivolts here and the ohm losses involved can't really be measured with the cheap VO meter that I have. Probably will upsize to #4 or larger wire size.

I just know that my ohm reading is as good as I can get it at this time. Figure its better then no zinc at all anyway... which is my other option at the moment...

fstbttms
21-07-2012, 19:20
Zinc will work, better then aluminum...
No it won't.

http://www.fotolode.com/images/fstbttms/Hull-cleaning/zinctypechart.jpg

sabray
21-07-2012, 19:29
No it doesn't. It means that the zinc depleted to the point that the screw wasn't under tension anymore and backed out.

I disagree unless the boat is not maintained. If the zinc depletes it should have no effect as the screws are not tensioned by zinc.Collar zincs have a sleeve that has the load. Not sure how cone zincs work but think they also have a load sleeve. Either way best to get the zinc back in its proper place. We agree on that yes.

sailorchic34
21-07-2012, 19:35
HUM. on the galvanic chart, aluminum is more noble (Ie lower voltage potential) then zinc, IE less current inductance, so zinc protects aluminum. Or more exact the induced current is lower in aluminum then in zinc. See chart below

http://www.corrosionist.com/Corros1.gif

I'm not sure how a aluminum anode would protect a bronze prop from zinc in the bronze leaching due to micro galvanic action. The galvanic potential does not seem to work between the two...

sailorchic34
21-07-2012, 19:38
Fstbttm's is right. The zinc corrodes to the point where the screw will sometimes loosen. Even with over 2/3 the zinc left...

The cone zinc's are just zinc no collar and then tend to wear from the inside as well as the outside. I actually do check my zinc's btw... and have found them loose sometimes after about 1/3 loss

fstbttms
21-07-2012, 19:41
I disagree unless the boat is not maintained.
I'm sorry but 18 years of underwater zinc installation experience tell me different.

Not sure how cone zincs work but think they also have a load sleeve.
If a prop (cone) zinc depletes sufficiently, the screw can easily be completely unloaded and free to move in either direction. In fact, it is not uncommon for these zincs to deplete in such a way that the main body comes completely off, leaving nothing but the screw and a small disk of anode material where the screw went through the zinc. Nothing securing the screw to the prop nut but threads.

fstbttms
21-07-2012, 19:43
HUM. on the galvanic chart, aluminum is more noble (Ie lower voltage potential) then zinc, IE less current inductance, so zinc protects aluminum.
I'm no physicist or electrical engineer. I just know what the zinc manufacturers tell me. :D

sailorchic34
21-07-2012, 19:56
I really should look in to a magnesium anode too I'm thinking, if I hang around the delta more. Zinc does have issues in fresh water plus it pollutes more. I'm not sure aluminum really protects the zinc in bronze prop's, It works for copper though. Me I would use zinc for salt and magnesium in fresh.

Power boaters could get away with aluminum I'm thinking... But then I've only studied corrosion a little and am not an expert. I do get feisty sometimes.... Feisty sounds better :whistling:

Stumble
21-07-2012, 20:43
Sailorchick,

Do you know exacally what alloy is in the prop? Sadly it seems most manufacturers of marine parts can't figure out the difference between bronze and brass, and use the terms interchangeably. Technically bronze doesn't use zinc as an alloying agent, and instead tin is used, while brass is a copper/zinc alloy.

Of course a lot of marine 'bronze' really has a good bit of zinc in it, but so long as there is less than about 15% zinc the alloy self isolates the zinc from saltwater. On a microscopic level basically the zinc corrodes away, but it is such a small part of the whole that there is a boundary layer of copper surrounding the rest of it. Once the electrolyte can't get to the zinc, no electrolysis.

On the other hand if you have a true bronze prop (and many of them are), then there is no zinc in the alloy to begin with, and what you are protecting is the stainless-bronze connection. Most likely actually the stainless, but it depends on exacally which grade of stainless shaft you have, and what bronze alloy you have. Most combinations are actually pretty close galvanicaly. It is typically the Mid alloy steel in the engine that really need protecting, not the prop-shaft connection.

sailorchic34
21-07-2012, 20:57
Your right.

Bronze most of the time has tin in it. Though now a days it can have zinc or any of a few other metals in it too. Odds are mine has tin as an alloy. Hey blonde moment. Sounds better then a senior moment anyway....

As rosanna rosanna danna would say..... never mind.

So with a tin alloy aluminum would work for bronze props. Though one would need to check to make sure.

Suzybro
21-07-2012, 21:02
OK, I admit that I scrolled down and did not even read all the responses. I am like...both arms in the air and all the way down to the floor. I admire you for...1 Knowing to check this, 2. Diving to check it yourself, 3. For being a do it yourself kind of gal. Kudos to you. I think I am way to accustomed to being "taking care of". I would be so lost and truly admire you. I am a tough girl and have survived being held captive in Russia. No lie...but just don't have that mechanical instinct. Thumbs up to you!!!

sailorchic34
21-07-2012, 21:05
So with the mild steel issue, do you think my zinc in the sea strainer idea, electrically connected to the engine works??? Well at least better then no zinc I'm assuming.

sailorchic34
21-07-2012, 21:07
What can I say, I learned most of the do it yourself from my dad. I also have a son how did two custom engine swaps (cars of course) before he was 19. So maybe it's in the blood.

Stumble
21-07-2012, 21:14
Aluminium has a galvanic potential of -.8, to -1.

The most galvanicaly active brass/bronze that should ever be on a boat for any reason, no matter how bad sits between -.4 and -.3

Unless you have some seriously high zinc brass (some artistic brass goes up to 50% zinc). Theoretically it also is -.4 to -.3, but there is so much surface zinc it never passifies, at least not until there are holes in it. But this stuff is usually used for decorative lamps, and interior architectural detail in houses.

Stainless is tricky, since different alloys can vary massively, and it has different galvanic potential in and out of the water. But generally marine stainless ranges from -.38 to -.58 depending on alloy under water, and 0 to -.1 above the water.

The problem is right at the water-non-water interface for stainless where you can get inter granular pitting. At least without some annode elsewhere in the system to take the load. But it only needs to be more cathodic than the below water cathode to work. So from an electrical standpoint a cast iron anode would be fine, but would obviously rust away in no time.

Stumble
21-07-2012, 21:17
So with the mild steel issue, do you think my zinc in the sea strainer idea, electrically connected to the engine works??? Well at least better then no zinc I'm assuming.

It's certainly better than nothing. But drive shafts are expensive, and the closer to the galvanic cell the better. I thik you are fine for a few days, or a couple of weeks. But I would go ahead and order the proper anode in aluminium.

Alternatively you could replace the drive shaft and prop with titanium ones :D and not worry about it anymore. :whistling::whistling::whistling:

fstbttms
21-07-2012, 21:22
So with the mild steel issue, do you think my zinc in the sea strainer idea, electrically connected to the engine works??? Well at least better then no zinc I'm assuming.
Do you have any kind of synthetic spacer in the driveline? If you do, your zinc is likely protecting nothing except maybe the strainer.

Andrew Troup
21-07-2012, 21:42
It's a little depressing the way new ideas get dismissed on forums like this. Whoever suggests them is automatically considered to be a neophyte, and whoever dismisses them generally portrays themselves as the fount of all knowledge.

Generally, some of the commenters will be in such a hurry to cement their reputation that they don't even read the thread properly.

fstbttms
21-07-2012, 22:22
It's a little depressing the way new ideas get dismissed on forums like this. Whoever suggests them is automatically considered to be a neophyte, and whoever dismisses them generally portrays themselves as the fount of all knowledge.
You know what? It doesn't take a rocket scientist to determine that not every new idea is a good idea. The OP came here looking for opinions about her ad hoc zinc arrangement, and she got them. In this case there were no raves of enthusiasm about what she is doing. Does that distress you? Gosh, I'm so sorry about that. :rolleyes:

cal40john
21-07-2012, 22:34
Manganese bronze which is commonly used to make propellers is actually a brass, it contains 39% zinc. A friend recently lost a blade, previous owner didn't maintain zincs. You can see the pink of dezincification where the blade fell off.

Bronze types:
Types of Bronze (http://www.bronzework.co.uk/Bespoke/bronzetypes.htm)

Here's why not to use zinc in fresh water.

From: Anode FAQs (http://www.performancemetals.com/anodes/AnodeFAQs.shtml)
Zinc anodes can become inactive after only a few months due to the build up of an insulating film of zinc hydroxide.

Seems to me a scrub of your zinc every few months would work.

From same site above, why aluminum alloy works. It's :
Navalloy™ (aluminum/zinc/indium alloy) with -1.1 V on the galvanic table.

(For myself 8 years in fresh water with zinc, took the maxprop in for reconditioning a couple of years ago as the blades get some slop over time shifting back and forth, they didn't find anything else wrong, as in no corrosion issues. Also I have no dock power which might influence what's happening.)


If you really want to read more than you ever wanted to:
Metal Corrosion in Boats
The prevention of metal corrosion on hulls, engines, rigging and fittings
by Nigel Warren

He writes about wiring zincs to nearby metals to be protected.

John

Andrew Troup
21-07-2012, 22:48
You know what? It doesn't take a rocket scientist to determine that not every new idea is a good idea. ..... In this case there were no raves of enthusiasm about what she is doing. ....

It follows from your statements, specifically from the qualifiers I underlined, that you must be aware of a number of threads on this forum where a new idea was met with "raves of enthusiasm" ....

or even widely acknowledged as possibly having some merit.

It would be helpful if you could provide links to these threads. I've not come across any.

Stumble
21-07-2012, 23:46
Cal40,

Manganese Bronze is used almost exclusively on ships propellers. Not boat propellers. These props are so massively different than what you will see on your boat it's barely worth the comparison...

First they are huge. Absolutely massive, think somewhere around 16-20" thick at the mid point. Most boat props could sit sideways in one of these monsters and not hit either side. They also have to deal with cavitation problems from the tips moving so quickly.

The other issue is simply cost. Unlike our props where we just want them to last forever, a commercial ship wants an economical solution.

There are also other concerns, like the speed at which the casting cools that have to be taken into account. Casting a part this size is its own special nightmare, requiring very precise engineering to ensure that the part doesn't rupture from thermal issues on its way from liquid to solid. This just isn't an issue with boat props, even if you have a 200' yacht, your prop is a fraction the weight of these things.

The other thing is that these ships are almost always made out of mild steel, which is just outside the galvanic compatability index of zinc anyway ( a .2v delta, where .15 is considered acceptable), so the problems they have to deal with are peanuts as compared to a private boat, where you will typically find a 304 shaft, 316 bolts, bronze wheel, Monel strut, ect... If you make it all out of the same alloy it's a lot easier to control.

cal40john
22-07-2012, 00:14
I have no idea what %age props are manganese bronze on rec boats but I wonder how many price point boats, or people looking for an economy prop use:

For the cruiser over 30', the 3-blade MP propeller has the blade area to get the job done. The thrust provided by the MP3 propeller not only produces cruising performance when the sails are down, but also offers excellent maneuverability while docking. - The MP3 3 blade fixed pitch propeller series for sailboats is available in diameters of 10" - 24", in a wide range of pitch. Custom sizes are also possible. The typical material for the Michigan Wheel MP3 propeller series is Manganese Bronze Michalloy K, although NiBrAl Michalloy XX (Nickel, Bronze, Aluminum) material is also available.

From:
Michigan Wheel 9" (3/4" shaft) Bronze Inboard Prop eller (http://www.shopyourway.com/michigan-wheel-9-3-4-shaft-bronze-inboard-propeller/172847776)

Note the Title of the Ad only says bronze propeller, only if you read the fine print do you see manganese bronze, then you have to know that this is actually brass. How many would look twice after seeing the name Michigan Wheel?

John
Cal40,

Manganese Bronze is used almost exclusively on ships propellers. Not boat propellers. These props are so massively different than what you will see on your boat it's barely worth the comparison...

First they are huge. Absolutely massive, think somewhere around 16-20" thick at the mid point. Most boat props could sit sideways in one of these monsters and not hit either side. They also have to deal with cavitation problems from the tips moving so quickly.

The other issue is simply cost. Unlike our props where we just want them to last forever, a commercial ship wants an economical solution.

There are also other concerns, like the speed at which the casting cools that have to be taken into account. Casting a part this size is its own special nightmare, requiring very precise engineering to ensure that the part doesn't rupture from thermal issues on its way from liquid to solid. This just isn't an issue with boat props, even if you have a 200' yacht, your prop is a fraction the weight of these things.

The other thing is that these ships are almost always made out of mild steel, which is just outside the galvanic compatability index of zinc anyway ( a .2v delta, where .15 is considered acceptable), so the problems they have to deal with are peanuts as compared to a private boat, where you will typically find a 304 shaft, 316 bolts, bronze wheel, Monel strut, ect... If you make it all out of the same alloy it's a lot easier to control.

sailorchic34
22-07-2012, 11:18
:popcorn:


I love CF. Its better then watching republicans and democrats debate.. :popcorn:

Well I do have 3 other prop zincs on board in my spares box, so when I get back to the salty water I'll see about having someone put one on.

I would love a titanium prop and shaft. I expect though that if I have to ask the price, Well...

I do keep up on my maintenance... except for the &^%$# prop zinc which keeps falling off and thats the &^$$ screw with it...

zeehag
22-07-2012, 11:21
i , for one, would like to know if that practice of placing in the screen works---please keep posted re this.

sabray
22-07-2012, 11:38
Still being dumb ass , if the zinc deteriorates to such extent that it cannot be maintained. Then there is galvanic action somewhere eating or transferring the electrode. Nothing left is not the design intent. Bad design bad install or electrolytic reaction. Get these right and your not sticking. zinc in place that we don't normally stick zinc.

Sir Rondo Normal
22-07-2012, 11:45
Simple... hope for the best until you can get a new cone anode (of the appropriate type for your application) and a new screw and re-install using threadlock. :)

sailorchic34
22-07-2012, 11:45
Will do Zee.

Oh for the question on my drive from the diver. Not no drive saver and anything like that. whoever put the engine in left only a 1/4" between the end of the drive coupling and the steps. (Its a v drive so the coupling faces the pointy end.

I did check that I have continuity between the shaft and seastrainer. Which can only be had with the wire I added, btw.. I do need a bigger wire I'm thinking too

I did come up with another way to mount the cone prop nut too. A redesign if you will. Design the zinc with an internal spring clip arrangment, Two clips 180 degrees apart, mechanically fastened to the zinc, put a 3/4" round disk on the end of the bronze carrier nut thats say 1/4" larger diameter. Then if properly designed the zinc would just slide on and clip in. The zinc needs a slightly different shape too to make the clip work.. OK so somebody make that so I can buy it In Zinc and Aluminum at least :)

zeehag
22-07-2012, 11:59
ok iam a dummy--how does prop stay on boat after zinc disappears from use and screw falls out--is there a secondary back up for the keeping of the prop??? i know some folks lost prop during cruising passages--curious...

sailorchic34
22-07-2012, 12:18
there's a nut and then the zinc carrier nut thingy. the cone prop zinc connects to the carrier with a screw. The bad news is as the zinc wears away it gets loose and can wobble around.

Looks like a design feature to me. So I'm trying to work out better ways to mount the zinc, without it falling off before its time.

Its different then a shaft zinc, btw, there is less contact patch with the cone zincs so they tend to wear out more from the end near the contact point then toward the prop.

fstbttms
22-07-2012, 13:54
Still being dumb ass , if the zinc deteriorates to such extent that it cannot be maintained. Then there is galvanic action somewhere eating or transferring the electrode. Nothing left is not the design intent. Bad design bad install or electrolytic reaction. Get these right and your not sticking. zinc in place that we don't normally stick zinc.
The zinc is designed to deplete, as all sacrificial anodes are. Left long enough and everything working as it should, it will deplete 100%. Maybe Chic didn't check it regularly enough. She has not said how long it had been on there. Your assumption that because the zinc is missing, there is an issue is wrong.

fstbttms
22-07-2012, 13:57
ok iam a dummy--how does prop stay on boat after zinc disappears from use and screw falls out--is there a secondary back up for the keeping of the prop??? i know some folks lost prop during cruising passages--curious...
The zinc mounts on a special cone-shaped nut which is secured to the shaft by a cotter pin. The zinc itself does not keep the prop on the shaft, so loss of the zinc and its screw does not mean the prop is going to back off the shaft.

http://www.fotolode.com/images/fstbttms/Hull-cleaning/zincprop.jpg

ixtlan22
22-07-2012, 14:08
So there's supposed to be zinc thing down there eh? I've had my boat for the last 10 years and nobody mentioned this to me...no wonder I can't get out of my slip...and all this time when I looked I just thought I had a really small prop!

David M
22-07-2012, 14:18
I was just trying to think of a solution for the machine screw backing out. Would Teflon tape create enough friction at the threads to prevent this? Obviously applying Blue Thread-Lock underwater would not work...but it might work hauled out. :)

I know what you mean Sailorchic, I used to use the zinc fairwaters (called that on ships). They were never still on there a year later when I hauled the boat out, so I started using zinc shaft collars, which did the trick.

noelex 77
22-07-2012, 14:20
The problem with zinc is that in freshwater it develops an insulating layer. You can remove his by periodicaly sanding the zinc, but unless you are you are prepared to do this an alternative anode material like magnesium is needed.

Your zinc in water filter will not be as effective as an anode on the prop. I doubt it will work adequately. Anodes need to "see" the material they are protecting. There needs to be a flow of electrons in the electrolite ( seawater). This will happen much less readily to a zinc in the seawater strainer then to a zinc bolted to the prop.

I do sympathise. I am good free diver, but replacing a zinc underwater while holding your breath is harder than it sounds.

The prop anodes are a very poor design. Painting around the screws of the zinc at your next hallout will stop them corroding around this area which helps stop them falling off. The wasting and consequent protection of the zinc will still occur over the central thicker area.

Hire a diver if you want your prop to last. Or learn to hold your breath a long time, relax, slightly hypventilate and try swallowing. Have someone watching out for you.

Sir Rondo Normal
22-07-2012, 14:22
Apply the threadlock to the screw before you go under. Let it set up, then it's like a nylock nut

sy_gilana
22-07-2012, 14:34
Hiya Sailorchick, As I have read several of your posts before, I know I am speaking to a peer or senior, in terms of engineering.

I have a 11 pound anode bolted into the floor of my seachest, I have magnesium ones in the bottom of my bilges in case of a leak of any type of water. I have anodes in my holding tank. I'm with you totally on this one.
Theoretically.

Now allow me to comment as a sailor, steel boat owner, diver, and Mr Fixit for a lot of boats over the last 14 years. Get a prop anode on there asap. Get ready in the water, have someone assist by handing you the allen? bolt inside the anode, head down with the allen key inserted. Use Loctite on the threads a good coating, and dive and insert it. The loctite will only set after a while, it requires O2 to go off. The anode will fall off, but the bolt will be there, and you can break it out again. Better yet it will rattle and tell you its time to change it.

I like your thinking.

zeehag
22-07-2012, 14:35
i adapt my collar zincs to use a lock washer so they dont fall off--when i dont do that, they go away and cause bad vibration---mine doesnt use a prop end zinc--just the collar. i have only had one fall since i began using lock washers with em

fstbttms
22-07-2012, 15:08
Apply the threadlock to the screw before you go under. Let it set up, then it's like a nylock nut
No, it's not. Normal threadlocker requires oxygen to work. Pre-applying it to parts to be assembled underwater does is not effective. To my knowledge the only product that can be pre-applied to parts and then assembled underwater is Loctite 248 (which I have only found online.) This from one of the parent company's engineers.

http://www.amazon.com/Loctite-QuickStix%C3%A2-Threadlocker-Strength-Removable/dp/B000132VH6

Sir Rondo Normal
22-07-2012, 15:16
No, it's not.
Ya... it is "like" as in similar to a nylock nut.
That is what loctite does, mimmicks a nylock nut.

To my knowledge the only product that can be pre-applied to parts and then assembled underwater is Loctite 248

Sorry for being too generic. Use Loctite 248 :banghead:

noelex 77
22-07-2012, 15:29
Threadlockers, like loctite, are anerobic glues. They set in absence of oxygen.
Establish a good metal metal metal bond and they will set.

Be careful when using these products you do not inhibit the electrical conductivity between the anode (zinc) and the metal ( such as the prop) that wish to protect.
Insulating the zinc, to prevent wastage, around the screws is preferable IMHO.

sailorchic34
22-07-2012, 15:38
Just FYI, thought I would measure the voltage between the prop shaft and the wire to the sea strainer zinc. Based on my trusty $12 voltmeter I get 11 millivolts with negative being toward the sea strainer zinc.

I also decided to check the potential directly at the zinc (with the wire and sea strainer cover removed) to the prop shaft and got the same reading

Of course what I need to do is hang a zinc on a wire over the side and measure the voltage between it and the prop shaft... So more experimentation is required.

But I am getting a voltage potential which is nice. It tells me that the Zinc is in circuit and doing its mojo.. Just not sure what the normal reading should be in fresh water..

Jim Cate
22-07-2012, 15:41
Actually guys you have it backwards about Loctite: it is an anaerobic adhesive. This means that for it to cure oxygen must be EXCLUDED from its surface. It must also be in contact with an active metal ion surface as well, but it is the exclusion from oxygen that triggers the reaction.

Think about it -- it stays liquid in the bottle (always at least half full of air, 'cause they only fill them half way for just that reason). It stays liquid when you apply it to the surface of the fastener. Then when you assemble the fastener and prevent air from getting to the Loctitie it sets up.

I'm not familiar with their 248 and can't comment upon its properties...

Cheers,

Jim

edit: oops, I see that Nolex beat me to the punch here!

Sir Rondo Normal
22-07-2012, 15:52
This is like a union meeting. An awful lot of talk for such a simple fix :)

sailorchic34
22-07-2012, 16:03
Good think I did not start an anchor thread. But I know better then that.

BTW, checked the abyc papers and found in salt water you want 200 millivolts difference between the anode and that being protected. Still looking for the fresh water readings..

http://www.abycinc.org/committees/E-02.pdf

fstbttms
22-07-2012, 16:19
Actually guys you have it backwards about Loctite: it is an anaerobic adhesive. This means that for it to cure oxygen must be EXCLUDED from its surface. It must also be in contact with an active metal ion surface as well, but it is the exclusion from oxygen that triggers the reaction.

Think about it -- it stays liquid in the bottle (always at least half full of air, 'cause they only fill them half way for just that reason). It stays liquid when you apply it to the surface of the fastener. Then when you assemble the fastener and prevent air from getting to the Loctitie it sets up.

I'm not familiar with their 248 and can't comment upon its properties...

Cheers,

Jim

edit: oops, I see that Nolex beat me to the punch here!
You both are correct, of course. In my defense, I have been brewing/drinking beer since about 10:00 a.m. :D

In any event, according to the manufacturer (whom I contacted after participating in a similar thread, maybe on this forum), Loctite 248 is the only thread locker that can be applied topsides and assembled underwater.

LeaseOnLife
22-07-2012, 16:24
The loctite 248 works underwater because it is a paste. The 'normal' blue loctite 242 is a thin fluid and washes away too easily in the water.

Sir Rondo Normal
22-07-2012, 16:28
lmao, the girl is talking technical and the guys are arguing over which goop to use. :thumb:

LeaseOnLife
22-07-2012, 16:29
i adapt my collar zincs to use a lock washer so they dont fall off--when i dont do that, they go away and cause bad vibration---mine doesnt use a prop end zinc--just the collar. i have only had one fall since i began using lock washers with em

Lockwashers won't help on the prop-zinc: The lockwasher works against the underlying material, the zinc, which will be gone, then the lockwasher can't work. On the collar zincs, I use lock-nuts.

zeehag
22-07-2012, 16:31
i have yet to use locktite on my zincs--a lock washer usually is sufficient.
i dont know much about the prop end zincs--but the collars do well with lock washers applied.

Stumble
22-07-2012, 16:34
Abou to stir up some more fun... But I like using loctite on zincs (except shaft zincs). While its great at keeping the parts together, it is also great at acting as an insulator. Exacally what you don't want in a anode system.

fstbttms
22-07-2012, 16:34
The loctite 248 works underwater because it is a paste. The 'normal' blue loctite 242 is a thin fluid and washes away too easily in the water.
Not so. There are many Loctite stick "paste" products that do not perform when used underwater. 248 works because it is a special formulation.

fstbttms
22-07-2012, 17:19
Here is the e-mail I received from the makers of Loctite when I asked them what product could be applied to parts topside and safely used on said parts when assembled underwater (other Loctite products can be used underwater, but must be first assembled and allowed to cure above water, which is obviously problematic when replacing anodes underwater):

From: richard.e.avery@us.henkel.com [mailto:richard.e.avery@us.henkel.com]
Sent: Monday, March 05, 2012 7:16 AM
To: Matt Peterson
Subject: RE: Henkel Inquiry - Case #: 00083412 [ ref:_00D301RJ1._50080IRF10:ref ]


If I am understanding you correctly, then this will not work. Loctite 243 will not cure unless it is between two pieces of metal and restricted of air, hence the name anaerobic. It will remain a liquid if you coat the bolt and just let it sit in open air. If you need a threadlocker that can be applied underwater, you will need to use Loctite 248 Quickstix or Loctite 249 Quicktape.

Regards,

Rick Avery
Technical Engineering Representative
Henkel Corporation | AG Industrial Products
One Henkel Way
Rocky Hill, CT 06067
United States
Home - Henkel North America (http://www.henkelna.com)

sailorchic34
22-07-2012, 17:31
Well I've been playing Mr. Wizard, Er well Miss Wizard today. So after failing to find the millivolt readings in fresh water on line. I went topside and got a bucket of river water. I put some in a clean plastic storage container and placed a stainless steel wire clamp and my bronze deck key in the water and measured the potential differential.. Got 300 millivolts which is pretty good.

Then dug up one of my spare zinc's and placed it in the water with the stainless steel bit and read 1100 ish millivolts. Wow.

Went back below and started cleaning the 40 year old bronze wingnut that my wire is connected too. Now I get about 110-120 millivolts. I expect the bronze rod and the zinc is friction tight on now has got some of that 40 year old corrosion on it too.

So once the zinc corrodes enough for me to pull it out, I'll take some sandpaper to the bronze bits. I'm even thinking of bonding a wire to the zinc and installing a threaded connection through the cap (water proofed of course). Gee I might get some aluminum rod from the hardware store and make some aluminum anodes to fit the basket.

In my on line surfing, I found that 50 feet is the maximum length of an anoid wire, above which no voltage is possible. The shorter the wire the better.

Will let you know how the blonde zinc works after a few weeks.... Or when my prop fails..

Now back to the thread compound discussion,

foggysail
22-07-2012, 19:08
Chic-- are you attempting to use the zinc in a bucket as a reference half cell?

Anyway, I long ago gave up totally on zincs. In fact, on my old Hunter 30 sailboat, I never used an anode. When I sold it after 25 years of usage, there were no signs of galvanic corrosion.

My current boat is a different matter. I use aluminum anodes, no, make that one (1) anode mounted on the boat's stern...in the water of course. Further I made 2 shaft brushes using oil impregnated sintered bronze that ride on each prop shaft to get better bonding than possible through the transmission's oil. And yes, it does bother me that I had to resort to an oil impregnated hunk of sintered bronze. I first tried using just pieces of bronze which wore unbelievably fast just resting on the turning shafts.

Finally, I measure the voltage between wetted bonded points using a silver-silver chloride half cell I was lucky enough to purchase on Ebay for less than $50. I measured last -0.76 on my SS shafts which is fine.

The readings should be less positive than -750mv for SS, -550mv for bronze and -800mv for mild steel when using a silver silver chloride half cell. Anything other than measurements is just plain guess work regardless of who the expert is.

Foggy

EDIT: The reference half cell can be other metals beside what I used. The advantage of using a known standard is there are published numbers of acceptable readings for various metals.

foggysail
22-07-2012, 19:25
Gee I might get some aluminum rod from the hardware store and make some aluminum anodes to fit the basket.

Now back to the thread compound discussion,


Now I know you're joking about making your own aluminum anodes because they consist of a mixture of metals that form an alloy. But a good thought anyway!

Foggy

sailorchic34
22-07-2012, 20:43
well Sort of... I figured its worth a shot. Ha good to know about the splintered bronze, as I was going to try brass strips on the shaft.

yes it is sort of guess work, though having a millivolt readings and comparing to published numbers for stainless and zinc least puts me in the ballpark. Though I don't know the type of stainless so yes its a bit of a wag..

Besides a -150 millivolts to the zinc in the seastrainer is better then nothing at all. which is how it would sit otherwise... Still got the old brain thinking about other options. I'm just a bit annoyed that the zinc was missing on the shaft...

Not to mention that my underwater skills are sorely lacking. Probably because I learned to swin in a lake outside Rudyard, Mi in june some time ago. Cold water up in the U.P. of Michigan in the summer. Of course learning to swim entailed splashing around for 5 minutes till your lips turned blue.

Jd1
22-07-2012, 21:39
Now I know you're joking about making your own aluminum anodes because they consist of a mixture of metals that form an alloy. But a good thought anyway!

Foggy

As far as I know, the anodes in domestic hot water tanks are available in different formulations and you might be able to get the right alloy. You might also find the right stuff with suppliers specializing in anodic protection.

sailorchic34
22-07-2012, 22:16
I thought about a water heater anode, Those generally are magnesium and come with a 3/4" threaded bronze plug.. Would work for the fresh water I'm bouncing around in now. but they are too reactive for salt water..

Most of the Aluminum anodes are alloys of aluminum also, about 95 to 99 percent aluminum, so I need to do a bit more research there. Maybe I can recycle my aluminum diet soda cans....;-)

Stumble
22-07-2012, 22:28
The proper alloy for aluminium anodes is MIL-A-24779

With the following recipea

*Zn- min. 4.00% - max. 5.00%
*In- min. 0.015% - max. 0.020%
*Si- min. 0.080% - max. 0.120%
*Fe- max. 0.090%
*Cu- max. 0.003%
*Others - max. 0.100%

The absolutely critical issue is the iron. Any more than spec can lead to a massive reduction in protection. Sadly cans run around .7 Fe.

Jd1
22-07-2012, 22:38
I thought about a water heater anode, Those generally are magnesium and come with a 3/4" threaded bronze plug.. Would work for the fresh water I'm bouncing around in now. but they are too reactive for salt water..


The magnesium anodes only work in hot water as far as I know but I am pretty sure you can get specialty aluminum anodes. I am not sure what they are used for but I am pretty sure they are available. Apparently zinc is less noble than steel in hot water hence standard zinc is (less than) useless in hot water.
Even if standard heater anodes are not available in the right alloy for your use, we are talking about a VERY common application for fresh water protection and you can use standard zincs for salt water use.

Markhunter1097
23-07-2012, 17:28
Isn't the easy solution to the prop anode falling off, is to paint the area around the attachment points? Another I read somewhere was to dab a bit of silicone to do the same. The silicone could also do the job of loctite, maybe. I haven't tried either as yet but will do at my next replacement date, currently every 2 months!

HopCar
23-07-2012, 19:16
I kind of like your idea of a zinc that can be changed from inside the boat. I don't have any anodes on my prop and shaft. All metal on my boat that touches the water is connected electrically to a large zinc plate mounted on the hull. It seems to work. The zinc goes away and nothing else. It sure would be nice to be able to change the zinc without getting wet or hauling.

sailorchic34
23-07-2012, 19:44
I've been looking at my 2" copper standpipe. I keep thinking replace the 2" elbow with a 2" tee and get a 6" ish long 1/2" or 3/4" diameter zinc's. That should work too. My raw water line is 5/8" so the inlet is oversized.

As would a seachest with a 1" seacock and 1" diameter zinc. A spare unused seacock could also be used.. Using #10 wire for bonding and maybe a splinter bronze strap for the prop shaft and away you go..

Maybe I should put together a kit... Though it's just bits and pieces...

skipmac
23-07-2012, 20:27
I kind of like your idea of a zinc that can be changed from inside the boat. I don't have any anodes on my prop and shaft. All metal on my boat that touches the water is connected electrically to a large zinc plate mounted on the hull. It seems to work. The zinc goes away and nothing else. It sure would be nice to be able to change the zinc without getting wet or hauling.

What? You're in Miami and worried about getting wet?

You do know that there are people from far away places that pay good money to come to Miami and jump in the water?

:p

HopCar
23-07-2012, 20:29
Several companies make shaft contact brushes as previously described. I think they use a carbon contact like those used in electric motors.
2436 - Shaft Brush (http://www.bepmarine.com/home-mainmenu-8/product-409/2436-shaft-brush)

Skipmac - Guilty, I'm just lazy.

bruce smith
23-07-2012, 20:39
I put in a marelon seacock and a plastic strainer to avoid having molecules of bronze going through my alloy engine.
The shaft and wheel being of course isolated.

sailinman
23-07-2012, 21:33
this wont help MUCH with regards to protecting your prop and drive shaft...

it will help... but the issue is ground POTENTIAL.... it will perform it's function and protect / sacrifice itself instead of ship metal that is exposed but it will do so with considderation of proximity to itself and the ship's metal ... the closer the ship's metal the more it will be protected.. the further away the less it will be protected..

the goal should be to place the anode on the shaft as it is the biggest/hardest/most expensive item that could be affected and possibly need replacement...

Nemo55
23-07-2012, 22:34
Correct me if i am wrong,but dont a cathode and anode have to see each other through an electrolytic medium to be able to swap charges/particles???
Does this mean you have your basket immersed over the side in view of the prop?
Sorry,,i had to ask..:popcorn:

Blue Stocking
24-07-2012, 05:15
Several companies make shaft contact brushes as previously described. I think they use a carbon contact like those used in electric motors.
2436 - Shaft Brush (http://www.bepmarine.com/home-mainmenu-8/product-409/2436-shaft-brush)

Skipmac - Guilty, I'm just lazy.

Bluestocking does not have room for a donut zinc on the shaft, and has a Drivesaver between the coupling faces. I therefore use a shaft brush as you have shown, but upgraded the carbon part to a much bigger one from forklift motor.
The bronze tension bar anchors to 1/2" bronze studs thru the hull, to which my zinc plates are attached. All tied into my #8 bonding.

sailorchic34
25-07-2012, 17:07
Well rather then hang the zinc over the side, which works too, there is the 2" seacock and standpipe to bring water to the basket strainer and zinc. So the zinc is physically about 24" to the side and 12" up from the prop.... in some of the same water as the prop sits in, so the circuit is complete.

Hopcar: thanks for the brush link... Another bit to get...

My intent is do do much like bluestocking but with the zinc in my over sized sea strainer. Makes for easy inspection and replacement.... maybe.

Like bluestocking, I have just 1/4" of my shaft is exposed outside the boat in front of the prop.

Cheechako
25-07-2012, 17:24
In theory a zinc attached to a wire, attached to the metal you want to protect and dropped over the side works. So maybe the zinc in the strainer will! Intuition tells me no for some reason.... OTOH if you notice when you remove a zinc from a prop shaft, the shaft is covered with white power... so how good a bond is that zinc getting...??????

sailorchic34
25-07-2012, 22:27
well being blonde I tend to go off in a tangent sometimes.. OK alot of times.

Why I have a 120V fridge running on an inverter, which everyone said would not work. 5 years later and its still running and using no more power then a 12V system. Cost less then $200

Why I have a led anchor light in a plastic mrs dash seasoning jar, zip tied to the aft stay. Its Bright too.. Total outlay of about $20


I expect I'll have some current path issues with the zinc in the strainer. But I'm going to play with it a bit and see if its possible long term. Sure would be easy..

One of the reports I read (think I posted it in this thread too) indicated that corrosion between the zinc and shaft is a problem and the better way was to bond a wire to the shaft and zinc, which no one does..

Nemo55
25-07-2012, 23:55
I luv it when schemes work out...carry on the fine work girl!!!!

skipmac
26-07-2012, 05:35
well being blonde I tend to go off in a tangent sometimes.. OK alot of times.

Why I have a 120V fridge running on an inverter, which everyone said would not work. 5 years later and its still running and using no more power then a 12V system. Cost less then $200

Why I have a led anchor light in a plastic mrs dash seasoning jar, zip tied to the aft stay. Its Bright too.. Total outlay of about $20


I expect I'll have some current path issues with the zinc in the strainer. But I'm going to play with it a bit and see if its possible long term. Sure would be easy..

One of the reports I read (think I posted it in this thread too) indicated that corrosion between the zinc and shaft is a problem and the better way was to bond a wire to the shaft and zinc, which no one does..

So if I decided to steal your anchor light idea would I have to use a Mrs Dash jar or could I substitute with a jar from a different spice? :whistling:

sailorchic34
26-07-2012, 10:25
HAHAHAHA I think the led spice jar might need to be in another thread. But, alot of spice jars are not clear some are redish, some brownish and some a milkish color.

Mrs Dash is clear and so far holds up to the UV. But its early. I just replaced my old glass spice jar as the old led anchor light had some burned out leds and the metal lid was starting to rust.

BTW I used a led bulb from superbrightleds.com.

18 High Power SMD LED 1156/1157 Tower Bulb Specifications (http://www.superbrightleds.com/cgi-bin/store/index.cgi?action=DispPage&category=OTHER&Page2Disp=%2Fspecs%2F1156-x18-T.htm)

Its Very bright and uses 0.1 amps an hour. 10-30V rated too. I just soldered wires direct to the contacts and taped the bulb to the wire for support..

Cheechako
26-07-2012, 11:11
I love handy women!

Vasco
26-07-2012, 11:24
[QUOTE=sailorchic34;998759

Why I have a led anchor light in a plastic mrs dash seasoning jar, zip tied to the aft stay. Its Bright too.. Total outlay of about $20


.[/QUOTE]

Hey, a salt shaker works much better, like a fresnel lens. This one had a GM sidelight bulb, before the days of led bulbs.
https://lh3.googleusercontent.com/-NivFmyPw5Rc/TSdyNkBxTnI/AAAAAAAAAuY/2evNvlZUYUA/s640/DSCN0859.JPG

SV Demeter
26-07-2012, 11:28
Did I miss something but arent you now sucking any depleted bits of zinc through your engine now? Or is the anode on the outside of the raw water strainer screen?

sailorchic34
26-07-2012, 11:59
Was woundering who would catch that. The zinc is on the sea side of the strainer, I did check btw. So anything large enough to damage the raw water impeller will be trapped in the strainer. The normal bits leaving the zinc from galvanic action will be quite small, less then a micron, probably atom by atom really , so not a problem

sailorchic34
26-07-2012, 12:02
HA yes a glass salt shaker would work too (for the led light.... darn thread drift), but mine are plastic and smaller...

sailinman
26-07-2012, 12:27
being handy and just making things is two different things...

your anchor light works, but is not legal... nor would it be considered safe.. does it function?? probably...

with the amount of exposed shaft, you have no choice but to go with what you got.... unless there is some other type of anode that can be placed on the shaft/propeller end (the threaded end)??? not sure if they make one or if that would fit with the small amount of threads left after the prop????

the wires to the shaft and then to the zinc will work also but the resistance in the wire needs to be counted for but that would be minimal...

the zinc in the strainer, not sure if that is fully submerged and or in contact with the water when the motor isnt running?

could the water syphon out of the sea strainer to the sea cock? is the strainer below water line?


is there any 'resistance' or other inhibiting factor thru the 'water column' in the hose to the sea strainer that would impede the anode from working fully? not sure....

but would love to see some numbers or some other 'success' stories...

but stories would be hard/diffiicult to extrapolate working models from as electrolysis is different from marina to marina, dock to dock... boat to boat....

last year, I used one zince for the entire year, and now at a different dock, I used one zinc in one month.... I didnt change anything in my boat during that time....

also, the brushes? do they have any 'friction' that would affect the shaft??? hopefully not much, if any???

sailorchic34
26-07-2012, 13:41
Actually according the to reg's my anchor light meets all the requirements. The light is wider then the backstay and has less then 3 degrees blocked by the mast or forward stays (I measured) plus its blinding bright.. so that 2 mile thingy is not a probem.. I'm sure the coasties who've passed me at o dark thirty would have complained if it was not up to snuff..

Yes the sea strainer is filled water all the time. The entire unit from the bronze sea strainer to the seacock is 1-1/2" and 2" copper and bronze, all 12"-14" of it. So lots of wetted contact area with the water.

I also checked the resistance in the wire connection from the sea strainer to the point of connection.

I'm not just a blonde bimbo, I'm an engineer.

sailorchic34
26-07-2012, 13:47
BTW, I'm at anchor every night, so my boat being seen is rather important to me. The mast head light, is not idea in areas with lights on the hills (SF bay area) or high rise condos such in southern Florida. Its actually darn near worthless in those conditions...

SV Demeter
26-07-2012, 14:01
Actually according the to reg's my anchor light meets all the requirements. The light is wider then the backstay and has less then 3 degrees blocked by the mast or forward stays (I measured) plus its blinding bright.. so that 2 mile thingy is not a probem.. I'm sure the coasties who've passed me at o dark thirty would have complained if it was not up to snuff..

Yes the sea strainer is filled water all the time. The entire unit from the bronze sea strainer to the seacock is 1-1/2" and 2" copper and bronze, all 12"-14" of it. So lots of wetted contact area with the water.

I also checked the resistance in the wire connection from the sea strainer to the point of connection.

I'm not just a blonde bimbo, I'm an engineer.


Give em hell Sailorchic. I wish half the clowns in my marina had your sense!

sailinman
26-07-2012, 14:43
FEDERAL REQUIREMENTS FOR RECREATIONAL BOATS (http://nyss.com/federal#3G)

i couldnt find any 3 degree rule, and I googled and found several mentions that the anchor light should be positioned on top of the mast or highest point...

it wont really matter unless someone hits you and insurance and lawyers get involved and show that you had a diy / non approved device that may or maynot meet reqts'

as for the zinc,

why would stray voltage go past the prop and shaft then go up and into a sea cock and thru a hose to make contact with the anode?

is the hose to thru the seacock always filled? or does the water run down the hose to water level? or is your water filter below water line?

thanks

Vasco
26-07-2012, 14:53
FEDERAL REQUIREMENTS FOR RECREATIONAL BOATS (http://nyss.com/federal#3G)

i couldnt find any 3 degree rule, and I googled and found several mentions that the anchor light should be positioned on top of the mast or highest point...



This is the worst spot for an anchor light. Just work your way through a crowded anchorage and you will know why. Whether in a dink or another boat nobody looks that high up when going through an anchorage. I tie mine to a jib sheet, at the bow, about 5 feet off the deck.

Lights at the masthead get confused with background lights if you're anchored off a built-up area.

cwyckham
26-07-2012, 14:58
FEDERAL REQUIREMENTS FOR RECREATIONAL BOATS (http://nyss.com/federal#3G)

i couldnt find any 3 degree rule, and I googled and found several mentions that the anchor light should be positioned on top of the mast or highest point...

it wont really matter unless someone hits you and insurance and lawyers get involved and show that you had a diy / non approved device that may or maynot meet reqts'

as for the zinc,

why would stray voltage go past the prop and shaft then go up and into a sea cock and thru a hose to make contact with the anode?

is the hose to thru the seacock always filled? or does the water run down the hose to water level? or is your water filter below water line?

thanks

Your own link says: "An anchor light for a vessel less than 50 meters in length is an all-around white light visible for 2 miles exhibited where it can best be seen". Arguably, this would make a mast top light illegal because it can't best be seen way up there. However, I don't think a New York Sailing School website is necessarily the definitive word on this one.

Voltage doesn't actually go anywhere as it is a potential field. It doesn't need to go "past the prop and up the hose". However, the ions do need to flow freely in the electrolyte, and I would wonder if there will be enough ion migration to make this work efficiently enough? I honestly have no idea, but I don't think there will be much mixing in the standpipe.

Sailor Chic, could you sketch the cell and ion flow for us schematically so we can understand what needs to flow through the electrolyte? I think we're all familiar enough with circuits and electrons to understand the dry part. It's the wet part that we're stumbling on.

sailorchic34
26-07-2012, 15:02
well the actual code is below:
Navigation Rules Online (http://www.navcen.uscg.gov/?pageName=navRulesContent#rule30) & 31

As to technical location and angles and such its below:
Electronic Code of Federal Regulations: (http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr&sid=a9fda2309970ca6ae93268c1355ebfa0&rgn=div5&view=text&node=33:1.0.1.5.39&idno=33%20%20%20)

Dude, chill. There is no CG approved anchor lights. There are lights citified by third parties to meet CG requirements, but the coast guard and FED requirements don't "approve" a certain type of light. Gee you can hang a kerosene lantern in the rigging and be 100 percent legal.

As to the zinc. because the zinc cell is at a lower reference voltage then the SS shaft or bronze prop. So negative is at the zinc from a galvanic standpoint.

The Sea strainer is anyways filled with water. The zinc is always in contact with the water

sailinman
26-07-2012, 15:05
i understand that point but want to avoid two scenarios, one is the over zealous coast guard type, and the other is an accident and the subsequent insurance and lawyer situations...

following the laws to the letter seems to be the way to go...., it may not avoid the accident and lawyer situation but at least you can say you followed the letters of the law...

i have seen and heard multiple stories on getting citations for anchor lights... one from a family that was on deck, with multiple white rope lights strung all over the boat, cabin lights all lit, but not anchor light on top of mast....

others had lights but coasties stated it didnt meet regs, for distance viewability... not sure how they tested it or how to present evidence to support or deny that ability,. except to have the mfg state it was tested under that configuration and approved..

i am currently in an approved anchorage, but 'this anchorage' still reqs anchor lights, even though the harbor is lit up pretty well with ambient lights from all around, so the chance of collision seems rare.. and of course about 75% are not using their anchor lights, unless alerted to an upcoming inspection...

sailinman
26-07-2012, 15:14
well the actual code is below:
Navigation Rules Online (http://www.navcen.uscg.gov/?pageName=navRulesContent#rule30) & 31

As to technical location and angles and such its below:
Electronic Code of Federal Regulations: (http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr&sid=a9fda2309970ca6ae93268c1355ebfa0&rgn=div5&view=text&node=33:1.0.1.5.39&idno=33%20%20%20)

Dude, chill. There is no CG approved anchor lights. There are lights citified by third parties to meet CG requirements, but the coast guard and FED requirements don't "approve" a certain type of light. Gee you can hang a kerosene lantern in the rigging and be 100 percent legal.

As to the zinc. because the zinc cell is at a lower reference voltage then the SS shaft or bronze prop. So negative is at the zinc from a galvanic standpoint.

The Sea strainer is anyways filled with water. The zinc is always in contact with the water


chill? i am chill... why are you defensive???

as for the technical verbiage or semantic of who or how something is approved, I bow to your 'correction'... but regardless my point is the same... if in the event of an accident when lawyers get involved, I would rather have an 'approved'/certified, or whatever by an independant party then a diy item in the discussion? I guess you would rather go thru the process of proving your diy item meets the requirement?

I did look at the link to the full context of the rules and requirements and still cant find the 3 degree waiver/release you mentioned earlier? (under section 30 for anchoring)... Is it somewhere else? if you know I would appreciate your posting that for me so I can put that in my folder, just in case...

Believe me, I want as much diy stuff as possible on my boat as long as it is safe, viable, close to the requirmeent and or a store bought item...

I have asked twice and guess I should give up on the sea strainer thing... but maybe this time will be different??

Is the HOSE from the SEACOCK to the STRAINER FILLED WITH WATER WHEN THE MOTOR ISNT RUNNING? CAN IT SYPHON DOWN TO THE WATER LEVEL LEAVING THE anode submerged in water but no water to conduct the ions from the anode to the open water area???

sorry to capitalize... I just want to be clear as this seems to not be answered yet...

thanks

sailinman
26-07-2012, 15:22
Your own link says: "An anchor light for a vessel less than 50 meters in length is an all-around white light visible for 2 miles exhibited where it can best be seen". Arguably, this would make a mast top light illegal because it can't best be seen way up there. However, I don't think a New York Sailing School website is necessarily the definitive word on this one.

.

therein lies the problem.. the arbitrary nature of words, WHERE IT CAN BEST BE SEEN...

from where??? from 3 ft off the beam? or from 1 mile out???

Is it more important to know where there is other boats anchored or whether or not you on an anchored boat already?

If you are in a boat under way, I think it would be best to know there are at least one anchored boat, ahead of me, so I can be on the look out... if I dont see that there are anchored boats until i am a hundred feet away, then I can not reduce speed and adjust course enough to miss that boat...

but if I know there is an anchored boat ahead, I can already reduce speed and be on the look out..

so in my mind, BEST SEN POINT would be the highest point on the ship with the brightest light possible...

but with 'arbitrary' words and all... all the sketches I found, show the anchor light ON TOP OF THE MAST...

no obstructions... cant be mistaken for a stern light or 'two stern lights'...thereby meeting two requirments, ALL AROUND and best possibility to be seen...

airplanes have to deal with 'background' lights and need to be trained and experienced in diferentiating the different navigation lights from a street light...

having to navigate a boat and look up on occasion to see a light vs, being lazy and just trusting what is at eye level is not prudent, imho...

nor compliant... but again, I am asking not really telling...

thanks

sailorchic34
26-07-2012, 15:43
Sorry I'm defensive because your being a little aggressive.

The angle thingy is in the appendix and reads:

b) All-round lights shall be so located as not to be obscured by masts, topmasts or structures within angular sectors of more than 6 degrees, except anchor lights prescribed in Rule 30, which need not be placed at an impracticable height above the hull, and the all-round white light described in Rule 23(d), which may not be obscured at all.

Sorry its angular sector of 6 degrees, which is 3 degrees either side of the mast. My bo..

Again you can't have an approved anchor light as there is no such thing. Certified just means that it meets the 2 mile distance viewing requirement and would be pretty meaningless in a court of law. I mean if I was a lawyer I would be asking how often you cleaned toanchor light lens and how often you checked the wiring for corrosion.

I have no hose between the seacock and strainer. I have a copper pipe that the sea strainer directly connects to. hard piped to the seacock. Sorry just not saying it again.

sailorchic34
26-07-2012, 15:48
The sea strainer is always flooded and the water is continuous to the outside.

sailorchic34
26-07-2012, 15:52
Hey my first Op thread that's longer then 100.. Go me...

sailorchic34
26-07-2012, 15:57
My experience is sailors look up but many a powerboater don't look up all that much. Specially after a beer or three... Its those people I would worry about.

For example, going into Richardson bay (sausalito) at night, A mast head anchor lights get lost in the background lighting on the hills. A lower light that also lights the deck is far safer..

sailinman
26-07-2012, 15:58
sorry for your thinking I was agressive.. I was being asertive?!?!?! j/king.. I really wanted to know and get as much info as possible...

thanks for the highlight to the 6degree issue...

and thanks for the info on the sea water strainer...

i been reading up on electrolysis and found lots to read and lots to be confused about...

as for your setup... I am not sure it will work with regards to galvanic corrosion

Corrosion and Electrolysis as applied to Fiberglass Boats (http://www.boatsurveyor.com/Articles/prevent_corrosion.htm)

the issue is the dissimilar metals of your shaft and prop, (assuming you dont have a stainless steel prop)

so, unless I am mis reading that article and or your intent on the anode, I am not sure that the placement of your anode will work best.. maybe better then none at all, but,.....

i really dont know what other options you may have either.... except to get a sst prop... and or check that area often...

thanks and sorry if I came off OFFENSIVE... nto meaning to...

ArtM
26-07-2012, 15:59
I don't mean this to be critical of anyone else, but it's just a newbie question.

Aren't zinc kits one of the first replacement parts someone would keep on board? I have never done it, but I remember when I was having a boat surveyed , the boatyard installed new zincs and billed me for it because they "knew that I would want it". This left me with the impression that this is a little item which is vitally important, not too expensive, and probably worth keeping an extra set around.

Do they require a diver to install? Is there some reason sailorchic wouldn't want to install them herself? I'm referring to a previous post where it was suggested that she would need to get a diver out to her boat, and that she needed a temporary solution until one could come.

perchance
26-07-2012, 16:02
My experience is sailors look up but many a powerboater don't look up all that much. Specially after a beer or three... Its those people I would worry about.

For example, going into Richardson bay (sausalito) at night, A mast head anchor lights get lost in the background lighting on the hills. A lower light that also lights the deck is far safer..


So how far above the water does the said anchor light have to be so it is visible at two miles?

sailinman
26-07-2012, 16:02
http://www.boatzincs.com/propeller-nut-aluminum-anodes.html

would something like these work?

sailinman
26-07-2012, 16:08
So how far above the water does the said anchor light have to be so it is visible at two miles?

depends on how tall said person is, but generally a 6' person can see 5 miles or more to the horizon..

sailorchic34
26-07-2012, 16:09
Hi artM. Well I do have lots O extra zincs. But the blonde chic forgot to get more screws, well allen head screws for the thing. Really need to add that to my spares list.

Its actually not easy installing a zinc on the prop or prop shaft without some means of breathing under water gear. Lets just say that that zinc replacement underwater is a Blue Job. Because I would drop the zinc, or screw or both before I had them connected on the shaft. I have tried and its just not going to happen. Plus I'm currently in the boonies of the Cali delta where getting a diver to make house calls is tricky...

Sailinman: we're Cool ;-) besides I like an argument now and then. Keeps me on my toes...

sailinman
26-07-2012, 16:13
also ,as i am thinking about the 6 degree thing... where was your light mounted/hung from in relation to the mast and how big is your mast? unless that light was some distance away from the mast, and assuming your mast is as big or bigger then mine, if you located it near the mast you will be more then 6degrees blocked... but then again, the boat is moving, the light is moivng and all that...

just sayin'

sailorchic34
26-07-2012, 16:14
Thats whats on my prop, well the brass bit, the zinc cone tends to wear away and once it's ~40% gone, starts thinking about dropping off. That and my amazing lack of coordination underwater, lead me to search for other options.

Will the zinc in a can work, well better then no zinc, least till I get to a diver...

sailorchic34
26-07-2012, 16:17
well the light is about 20-22 feet behind the mast and my mast is oh maybe 8" wide. I took my bearing compass and checked the arc from one side of the mast to the other and it was somewhat less then 5 degrees.. So I called that good.

Trig would work too, but I'm lazy...

OK so 4.5 degrees of arc. Oh my light is 17' away, the chainplate is 20' away.. Darn blonde moments...

sailinman
26-07-2012, 16:22
yea, almost any distance away from the mast will give it that radii

cal40john
26-07-2012, 16:51
being handy and just making things is two different things...

your anchor light works, but is not legal... nor would it be considered safe.. does it function?? probably...



On a recreational boat the nav lights are required to meet distance and color requirements listed in the appendices already cited. They are not required to be certified.

As of 2002 boat manufacturers are required to install certified lights.

https://www.federalregister.gov/articles/2001/11/01/01-27385/certification-of-navigation-lights-for-uninspected-commercial-vessels-and-recreational-vessels

sailinman
26-07-2012, 17:10
as i mentioned previously, the reason for certification is for the laywers and courts... it is easy to say that you have 'certified' equipment on board and present manufactures info, or you can prove that your equipment meets the requirements.... I for one would rather have the burden of proof on others, rather then myself... just one less thing to worry about...

ArtM
27-07-2012, 09:15
Lets just say that that zinc replacement underwater is a Blue Job.

"Blue Job"?

sailorchic34
27-07-2012, 09:56
Sorry girl talk.... blue jobs are for guys,, Pink for girls. Though ok I do alot of blue jobs too. Welll all of them so far but the *&@##$% prop zinc.

cwyckham
27-07-2012, 10:40
Hi artM. Well I do have lots O extra zincs. But the blonde chic forgot to get more screws, well allen head screws for the thing. Really need to add that to my spares list.

Its actually not easy installing a zinc on the prop or prop shaft without some means of breathing under water gear. Lets just say that that zinc replacement underwater is a Blue Job. Because I would drop the zinc, or screw or both before I had them connected on the shaft. I have tried and its just not going to happen. Plus I'm currently in the boonies of the Cali delta where getting a diver to make house calls is tricky...

Sailinman: we're Cool ;-) besides I like an argument now and then. Keeps me on my toes...

I just installed a couple shaft zincs underwater. Took a few dives (and hyperventilating before diving) to start getting used to the idea of how to do it.

There's no rush, so if you can get the zinc in place and a single turn on the screw in one dive, you can take the rest of the day to finish screwing it on. I put a lanyard on the hex key.

I was pretty darn proud of myself when I got it done.

Sounds like you're better at most blue jobs than I am (and my domain is supposed to be the blue jobs, in theory). Maybe this should be a personal goal...

Stumble
27-07-2012, 10:59
as i mentioned previously, the reason for certification is for the laywers and courts... it is easy to say that you have 'certified' equipment on board and present manufactures info, or you can prove that your equipment meets the requirements.... I for one would rather have the burden of proof on others, rather then myself... just one less thing to worry about...

As a reformed lawyer, this is really a lot of worry about nothing.

It would be pretty easy to just take a duplicate LED light it up, and take some pictures from 2 miles away as proof it is visible. And certified doesn't mean that much. If the light in question isn't visible from 2 miles, that is what's going to be called into question.

As I think someone mentioned, I would be looking at the last time the lense was cleaned, if the lense was cracked, or abraded, diminution of the brightness over time, ect... A certified or non-certified light would just be part of the question.

zeehag
27-07-2012, 11:08
i have a trusted dive service do mine--or a good friend...and i get the update on condition of hull as well as cleaning and zincs changed out. all for one dollar per foot.

SV Demeter
27-07-2012, 11:09
i understand that point but want to avoid two scenarios, one is the over zealous coast guard type, and the other is an accident and the subsequent insurance and lawyer situations...

following the laws to the letter seems to be the way to go...., it may not avoid the accident and lawyer situation but at least you can say you followed the letters of the law...

i have seen and heard multiple stories on getting citations for anchor lights... one from a family that was on deck, with multiple white rope lights strung all over the boat, cabin lights all lit, but not anchor light on top of mast....

others had lights but coasties stated it didnt meet regs, for distance viewability... not sure how they tested it or how to present evidence to support or deny that ability,. except to have the mfg state it was tested under that configuration and approved..

i am currently in an approved anchorage, but 'this anchorage' still reqs anchor lights, even though the harbor is lit up pretty well with ambient lights from all around, so the chance of collision seems rare.. and of course about 75% are not using their anchor lights, unless alerted to an upcoming inspection...


Is this REALLY true? I have NEVER heard of someone getting a citation or being hassled by the coast guard over their anchor light or lack of one. Where specifically did this happen? I want to make sure I never go there. I frequently see boats all over the place anchored with no lights. Not saying its a good idea just surprised that the coasties have time a resources for this sort of stuff.

sailorchic34
27-07-2012, 13:39
I just installed a couple shaft zincs underwater. Took a few dives (and hyperventilating before diving) to start getting used to the idea of how to do it.


My problem is I'm, hum...a bit more bouyant in certain areas. So its way too much fun getting to the prop and staying there long enough. OK I probably need a weight belt.. another thing on my list.....

I've not paid to have the bottom cleaned in almost three years. I find that just moving the boat is enough to get most of the soft growth off, what little there is. OH I do scrub the water line, that gets a little messy now and then.

Costs $2.50-$3.00 a foot in the bay area for a diver. $20 to change the zinc which I have on hand...

cwyckham
27-07-2012, 14:00
My problem is I'm, hum...a bit more bouyant in certain areas. So its way too much fun getting to the prop and staying there long enough. OK I probably need a weight belt.. another thing on my list.....

I've not paid to have the bottom cleaned in almost three years. I find that just moving the boat is enough to get most of the soft growth off, what little there is. OH I do scrub the water line, that gets a little messy now and then.

Costs $2.50-$3.00 a foot in the bay area for a diver. $20 to change the zinc which I have on hand...

Yes, I did use a weight belt. I'm still slightly buoyant, but my hull is fairly flat by the prop, so I just float up against the hull and that helps me stay in place

sailorchic34
27-07-2012, 14:10
ah, My boat has a rear overhang too, so it slopes up. I did find that a toilet plunger helps, but then one hand is trying to keep me in place.....Not my element I'm guessing...

sailinman
27-07-2012, 14:16
Is this REALLY true? I have NEVER heard of someone getting a citation or being hassled by the coast guard over their anchor light or lack of one. Where specifically did this happen? I want to make sure I never go there. I frequently see boats all over the place anchored with no lights. Not saying its a good idea just surprised that the coasties have time a resources for this sort of stuff.


if the area is an official anchorage, then lights arent required, unless stated differently...

the area I am referring to is Marathon, FL...

I have heard that the local officials, come thru the harbor 2-3 times a year and perform sweeps.... they look to see that the wye valves is secured/loced out, and that you have proper anchor lights, and safety gear... they start with the boats that arent lit up at night first...

again, this is hearsay as I have only heard the stories, and the stories have been 'both ways'.. some say it is a problem some say it is ok to hang a light from a halyard or from the rear stay...

sailinman
27-07-2012, 14:19
the info I found on the shaft zincs state that the screws are held in place by imbedded nuts / washer / retainer somethings..

as for the lanyard on the allen wrench, that is a good idea, I was thinking of gluing the allen wrench into the head of the allen screw until you get it tightened and then just break/wiggle it out....

ArtM
27-07-2012, 17:17
Sorry girl talk.... blue jobs are for guys,, Pink for girls. Though ok I do alot of blue jobs too. Welll all of them so far but the *&@##$% prop zinc.

I found several possible definitions for the term. I assumed this is the meaning you intended.

My next comment was going to be that some would consider Engineering to a "Blue Job".

Not me though...

sailorchic34
27-07-2012, 19:06
Yes, still not that many women in engineering, but more now then 33+ years ago. Really I started out as a draftsperson.

That whole engineering thingy was sort of an accident, I read alot. So on lunch breaks way back, I pretty much went through all the engineering books/manuals (ashrae, aspe, nec) plus all the building and fire codes. then all the manufacturers catalogs. Once I finished that I read the computer books and taught myself C/C++, VB and some assembler just for fun.

Well one thing lead to another and one day I found myself with a PE and the senior manager designing high rise buildings (well among other things).

It sort of just happened that way, just because I like to read a bit...

So thats the short brief on the whole engineering thing.

ArtM
27-07-2012, 21:44
It sort of just happened that way, just because I like to read a bit...


I have a 16 year old daughter who likes to read. It does not appear to be leading her toward an engineering career!

I've heard it said that men like sailing and women don't because it's very technical - basically an extended exercise in engineering and mathematics.

Therapy
28-07-2012, 10:35
if the area is an official anchorage, then lights arent required, unless stated differently...

the area I am referring to is Marathon, FL...

I have heard that the local officials, come thru the harbor 2-3 times a year and perform sweeps.... they look to see that the wye valves is secured/loced out, and that you have proper anchor lights, and safety gear... they start with the boats that arent lit up at night first...

again, this is hearsay as I have only heard the stories, and the stories have been 'both ways'.. some say it is a problem some say it is ok to hang a light from a halyard or from the rear stay...

To help continue the thread drift :p This is like an anchor thread :whistling:

Marathon is (sort of) a different planet. Crowded with lots coming and going, including CG traineeeees whom (who?) have their interpretations of "regulations". Not sure they all know how to read the same. :(

No offense meant to the CG. :flowers:

SV Demeter
28-07-2012, 15:11
To help continue the thread drift :p This is like an anchor thread :whistling:

Marathon is (sort of) a different planet. Crowded with lots coming and going, including CG traineeeees whom (who?) have their interpretations of "regulations". Not sure they all know how to read the same. :(

No offense meant to the CG. :flowers:

I have heard nothing good about marathon from cruisers. Crazy fees no anchoring derelict boats. I have no plans of ever cruising there for this very reason. It's a shame because as a kid I lived aboard for a year and we spent a few weeks there anchored. Was a great spot I'm sad to hear it has been ruined. As for an anchor light I still have one I bought thats battery operated and meant to be hung. Even has a photo cell. I guess it's illegal in marathon...

ArtM
28-07-2012, 23:32
the area I am referring to is Marathon, FL...

I have heard that the local officials, come thru the harbor 2-3 times a year and perform sweeps.... they start with the boats that arent lit up at night first...


In that area (meaning So Florida in general), there are a lot of derelict boats - that may be their main purpose - using lighting regulations to root out abandoned and powerless vessels in populated areas.