Breaking All the Rules ...

[cpa]

Glad to hear that things are going good for you. I can't wait to see the progress. Keep up the good work.

[KASHMIR]

In my experience stainless steel screws are fine in aluminium if Durlac is used. It always amazes me that outboard motor manufactures don't use it. But I guess their motors would not need replacing as often.


Sent from my iPhone using Cruisers Sailing Forum

[Wotname]

Originally Posted by homeless

.............
I have also started painting the sun and water damaged veneer in the pilothouse white. Still not sure about this, but is certainly easier to paint the ply around the windows than replace it, and if it looks too bad I can still replace it at a later date. Using an oil based paint over the existing oil based varnish, so will probably need at least 3 coats. Much harder to paint with white than varnish, as I now have to clean up every drip, smear, spatter.
..............

FWIW, I have started using a Hemple Primer/Undercoat and it is by far the best "oil based" primer/undercoat I have ever used (and I have used many different products both trade and retail).

What impressed me was the fast recoat times around 3 hrs at 20 degrees (C) and it being very very opaque (white). While it isn't a true hi-build undercoat, it was quite close. It brushed very well and I had no problems over coating with traditional gloss enamels.

I have no association with the product other than as a very satisfied user. It has now become my "go to" undercoat. I still prefer to use other products for primers but that maybe me being reluctant to change

[Terra Nova]

Originally Posted by homeless

...
Work planned for the yard :-
1. inspect the bottom, prop, rudder for paint, corrosion, anodes etc.
2. get advice on how to do the antifouling work myself
3. clean the area around any corrosion and grind off the glass patch in the bilge
4. get any pin-holes or pits welded
....

While it is hauled out is the opportune time to hire a certified marine surveyor. Surely any insurance company will require it.

How will you locate any other pinholes?

[homeless]

I have third party insurance with Pantaenius which is very reasonably priced, but more importantly did not require a haulout or survey like some other insurers. If I needed to have a survey to get insurance, then I would not have bought the boat, because all marinas require insurance, and I have now waited 10 weeks to get the boat out of the water.

I guess a recent survey may make the boat easier to sell, so I will consider it after the hull and engine are done.

Pinholes are easy to find as they weep water. To find pits that may soon become pinholes I will wire brush the bilges to remove paint flakes, look for signs of the white jelly or salt crystals that indicate aluminium corrosion, look for deformed paint surfaces that indicates underlying corrosion, and hold a light at a tangent to the aluminium plate surface to make it easier to see the pits. If they are in welds then a good wire brushing and visual inspection will be the best I can do.

[homeless]

The trip up the Coomera river was surprisingly easy at high tide, with plenty of water under the keel. The only stressful time was passing Hope Island Marina where there is an island in mid stream with large trees on it that does not appear on my chart, the water got shallow, and it was not clear which side of the island I should pass on. In the end I passed the island on the marina side and there was enough water.

Arrived at the yard today and they said they could not lift me until my wind generator and satellite antenna were removed as they blocked the travel lift, but they could not wait until I did that work as it would delay other lifts, so my lift was bumped until tomorrow, and I was moved to a marina berth.

So ... the only work today was to mask off the pilothouse windows and apply another coat of white paint.

[dbostrom]

Cliffhanger! All will soon be revealed (or everything below the boot stripe).

[homeless]

The boat is now on hard stand, and water blasted. The lift was about 2 hours after low tide, so timing was not great, and I had to run the engine at full throttle to plough through a foot of river mud to get to the ramp.

Surprisingly the two part putty blob I put on the hole I found in Sydney was still there after quite a long voyage in some rather large waves. After removing the epoxy and glass patch and cleaning it up it is a single hole of about 5mm diameter. Will talk to a welder about filling it.

It was a hot day, but after about half an hour I noticed there was a small patch of hull that was still wet, so suspected water must be coming through the paint from inside the boat. I ran a paint scraper over it, and a stream of diesel started to flow, then get bigger, and bigger, and bigger. I put my finger over the hole to stop the flow, but everybody nearby is working with grinders or water blasters, so won't see me or hear me if I shout for help, so what to do??? Took my finger off the hole and raced up the ladder into the boat to grab the two part putty. My first attempt with the putty failed as in my rush I did not mix it properly, so it came off, but my second attempt worked and the putty set in the hole, reducing the flow to a trickle.

By this time probably about 50 litres have spilled, and are running downhill to the drain that probably leads to the river. Panic number two. Who to report the spill to, as Australian has some rather strict laws on Health and Safety and pollution. Covered in diesel I ran over to the nearest workers to get their attention and let them know there had been a fuel spill and to be careful with sparks, flames, cigarettes etc. (yes, they laughed at me). Then ran over to the office to ask for advise on spill cleanup. There was a bin of saw dust, so I grabbed it and back to the boat to stop the diesel getting to the drain.

After all of this, I went back up to the engine room, shut off the connection between port and starboard fuel tanks, shut off the port fuel tank outlet, then connected the fuel pump to the port tank return line. This allowed the pump to move the fuel from the holed starboard tank to the port tank.

When the starboard tank was empty I removed the putty, and cleaned up the hole in the hull. I can put my little finger through it, so am lucky it happened on land instead of at sea where I would have lost the fuel and/or had it contaminated with sea water. About 8 inches from the fuel tank hole there was some paint deformation, so I ground it off and after cleanup found another area where the hull was corroded through, but this time underneath the shower. Further down the hull I found a third new hole that was completely open and not covered by paint. A few hours with a hole saw and a hammer and chisel found that it was underneath wood below the toilet.

So now I need to clean up all 4 holes, and look around for any areas where the plate is pitted or thin, then talk to a welder.

In all, I am not surprised about the new holes, but good to find them and get them fixed all at the same time.

To make myself feel better I polished the prop and shaft to a perfect shine.

[atoll]

something to bear in mind when welding on the outside of the hull you will need to setup an effective wind break ,otherwise the welding gas gets blown away causing the MIG wire to stick.

also a handy tool to have is a titanium nibbler bit for your drill to clean up holes.

welding patches over the holes might be easier and more effective than trying to in-fill corroded areas.

[dbostrom]

I think this boat was an excellent choice for the sole reason that Lady Luck is smiling upon her, 24 hours a day. Even the circumstances of the diesel fountain were very fortuitous (after all, Lady Luck only bends the rules, cannot break them).

[As well, Homeless seems well equipped to create that little bit of extra, artisanal luck needed to finish bending the rules just enough to see another day above sea level.]

[Terra Nova]

Originally Posted by homeless

...So now I need to clean up all 4 holes...
To make myself feel better I polished the prop and shaft to a perfect shine.

Instead of polishing stuff, I would be looking for all the holes you have not yet found. Sandblasting the hull, below the waterline, would be the prudent thing to do.

[europaflyer]

Originally Posted by Terra Nova

Instead of polishing stuff, I would be looking for all the holes you have not yet found. Sandblasting the hull, below the waterline, would be the prudent thing to do.

+100000.... Full assessment of the corrosion state of the hull below the waterline. More than anything, find the source of the stray current which is eating your hull away! Think through the whole electrical system. Aluminium hulls don't just corrode themselves...

Keep at it...

[NSboatman]

As a Fellow that also ended up with a metal boat with significant pitting and corrosion damage in places (currently under repair... Me and the welder are new best friends); i am loving reading this!

I'm dealing with steel issues, under a temp building in a Canadian winter... But the discoveries sound very familiar. So far we've elected to replace about 25 sq ft of plate, and fill in a few dozen pitted areas, and even though it is tough and looks bad while in progress- it will be 100% when done, and we'll know it.

That 4.236 is a fabulous base engine. Eminently rebuild able and worthy of the effort.

You keep going homeless- you clearly have the cojones to pull this off.

Bg


Sent from my iPad using Cruisers Sailing Forum

[homeless]

Since I need to get a welder in anyway, I pulled out the 6 through hulls left over from previously removed freezer, air conditioner, and generator so I can get the holes patched.

After those six through-hulls are welded closed I will only have another 14 through hulls left ... so also considering whether to replace them before painting the boat.

There are quite a few patches on the pilot house, cockpit, and dorade vent boxes where the paint was deformed or flaking and I could not be sure if there was corrosion or a paint fault. I wandered around today grinding back all the deformed paint I could see to check if there was any corrosion. Almost all of the deformed paint was due to poor application of previous coats of paint over older coats that were flaking or loose. The boat is nicely faired, so good to look at, but this was achieved by fairing with putty before the top coat. By grinding back the paint I also damaged the fairing, so will either need to replace it (unlikely) or live with a rougher paint surface. This is probably why previous owners decided to paint over loose paint knowing it would not last, rather than grind them back and prime again.

There are some suggestions above to blast the hull to look for corrosion. Corrosion is coming from inside the boat, so the plate looks fine on the outside until it breaks through. You could sand blast the bottom today, see nothing, then in a month have a new hole. The only way to find all corrosion would be to rip everything out of the inside of the boat that touches the hull and completely rebuild which is not practical. All corrosion found has been in low oxygen environments or close to dissimilar metals, so not sure why electricity is being blamed, and this is further confirmed by the three new holes found -

1. corroded by water in the bottom of the fuel tank under diesel (low oxygen)
2. corroded between damp wood and hull plate under shower (low oxygen)
3. corroded between damp wood and hull plate under toilet (low oxygen)

Where the boat is dry and well aired, the aluminium plate is perfect as the day it was rolled, but there it is covered by another plate (inspection hatches, deck hardware, exhaust vent etc) or wet wood then you can sometimes find evidence of corrosion.

Best option to avoid or reduce the corrosion would be to allow oxygen to get to all surfaces (don't paint, weld on hardware instead of bolting, dry bilge, fix deck leaks, fix toilet and shower runoff, inspect fuel tank etc).

[Mirage Gecko]

Originally Posted by europaflyer

+100000.... Full assessment of the corrosion state of the hull below the waterline. More than anything, find the source of the stray current which is eating your hull away! Think through the whole electrical system. Aluminium hulls don't just corrode themselves...

Keep at it...

Really not sure if the last sentence is correct.
In OZ we have what is colloquially known as a tinny but in reality is an aluminium dinghy or runabout or bigger.Over the years I have seen plenty of these that live out of the water and without ever having electrical current on board be far thinner than when they were made.Corrosion without electrical current?