Windlass Help, Please !

[ti325v]

Hi All,
Boating newbie, here please bear with me if I sound a bit stupid...
I have received terrific support from this forum in the past and was hoping to glean a bit more wisdom.
My situation:
15 x 4 meter dive boat pictured below.


I would love to have an electric horizontal windlass below deck to raise my amazingly heavy anchor.

Now the hard part.
I am located in Vietnam, on a remote island, and my boat was the talk of the island having technological marvels such as demand water pump, automatic bilge pump switches..I think you get the idea that they are in the dark ages here.
Anchor lines are about 1 1/4 inch manilla. Nobody uses chain on anchor roads. There are hundreds of fishing boats here and they all use anchors very similar to the one pictured below, as do I.
Currently my anchor is of this type pictured below, we anchor in sand, and weighs about 70 pounds / 30 Kg.
Kedge type.

I have found a 12 or 24 volt horizontal windlass
For about $600.
this is rated at 1000 watts. I can get a 2000 watt for about $800.

I have 2 x 200 amp hours in series to start the engine (24 V,) with a 60 amp alternator and 2 X 120 amp/hours for the house batteries in parallel with an 100 amp alternator.

The anchor is raised 2 times in three hours of running when we go out.
I have no draw except running lights and nav instruments on the 12 V system, and just the engine on the 24 volt system.
This boat weighs a whole lot ! 2 inch tropical hardwood hull, builder told me 50 tons ! I have not calculated the displacement, but it might be about right !
Local conditions, we sometimes anchor in moderate current ( 1 Knot) any more and we drift dive.
Always anchor on clean sand bottom. The boat is always manned when not on solid moorings. Maximum depth on anchor is 18 meters.

To top it off....I need to do this on a budget, ( I know boats and budget are mutually excursive words)...

I would be grateful for advice on how to best put this system together.

1) I may be able to find locally a danforth anchor, how much should it weigh ?
2) If I stick with the current anchor will 1000 watts be enough ? I can get a 2000 watt unit.
3) Should I use 10 or 12 mm rope and how much and what size of chain ?
4) Should I run the winch off the 12 or 24 volt system ? the 12 v can easily be reconfigured to 24 as a back up starting system. ( 2 alternators)

Any other thoughts or advice will be greatly appreciated...
I hope I have provided enough information, if not please let me know.
Thanks in advance for your help !!!
Larry

Have to run, cannot insert photos for some reason, will return tomorrow with a follow up with photos

[captain58sailin]

If you use a 24 volt system it will draw less amps for the same work. You might want to consider going with hydraulic for your windlass, using a 12 gallon pump equipped with an electric clutch belt driven pulley mounted on the engine opposite of your alternator. Given the area of operation it might prove easier to keep running, also you could equip yourself with a hydraulic pot puller, in case you are in an area where you can catch shrimp and crabs, or fish pots. My experience with electric windlasses is limited and every time I have had the opportunity to use one, it failed after a short amount of time used. I have used hydraulics a lot and the only trouble I've had was when we put a hook through one of the pressure lines which was quickly remedied with a splice joint. If the electric magnetic clutch should fail, you can always use a couple of bolts to secure the clutch and at least get your anchor up.

[GordMay]

The two things to consider are the Maximum Pull Capability and, the Working Load of the winch. Maximum pull (sometimes referred to as stall load) is the maximum short term or instantaneous pull of the winch. Working load is generally rated at about one third of the maximum pull, and is usually considered to be the load that the winch is pulling once the anchor is off the bottom.
To determine your required maximum pull capability:

a) Maximum Pull (in pounds) = Total Weight of your ground tackle (anchor + Chain + Rope) x 4 .
Pick the nearest LARGER pulling power. The factor of 4 covers the effects of windage and the speed of tidal current and includes a safety margin for unknown circumstances.

b) Use the manufacturer’s recommendations.

See also ➥ http://www.cruisersforum.com/forums/...ion-14928.html

And ➥ http://www.cruisersforum.com/forums/...lass-1475.html

[ti325v]

Hi Gordmay..
Thanks for your advise.
Is it really that simple ?
If that is the case the 1000 watt should be plenty.
Considering the max load of the winch is 1600 Kg, and the max pull is 300Kg.
30 Kg of anchor, 30 Kg of chain (?????) = 60 kg x 4 = 240 kg...looks like I am far above what I require.
Suggestions on rope thickness ? chain dimensions ? I would like to go with 1/2 " but that may be to light, 5/8 will limit my amount of anchor rope...think it is strong enough if I can get some good quality stuff here in the back of beyond ?
Should I get rid of that massive anchor ?
Thx again

[CarlF]

If you are serious that you only plan to use this anchor in light to moderate conditions on a sand bottom with the boat actively manned then your least expensive option is a good small anchor with a new light rode (with the big anchor as backup)

Try to calculate your actual pull some day (how many guys are needed to hold the line). I'd be surprised if it was more than a few hundred pounds.

Get an anchor rated for five time that pull in sand. Same with the rode. This will be very small (say a 7lb aluminum Fortress and 3/8" rode). Just because that will look silly, you might go up a bit. Put 10ft of 1/4" chain on too to help a quick set. In these small sizes, I'd favor galvanized steel over aluminum because the weight will dig in quicker (although I bet the Fortress people disagree)

What you care most about is quick reliable setting. Be careful of knockoffs because even a tiny angle difference can make a huge difference. Also don't be afraid of used anchors from quality manufacturers. An old Danforth or Bruce would be a great choice.

Obviously never use this rig in harsh conditions or when leaving the boat.

Carl

[ti325v]

Hi Carl
Great and helpful info.....
Yes conditions are exactly as I described, boat staff is three man on board whenever there are divers in the water....This is the boat....
Scuba, vietnam, Con Dao, Snorkeling


My captain advises this current monstrous set up, and I appreciate his concern, but this thing is not run as a fishing boat, from which he bases his experience.

From my reading it is way over kill. Now that you have seen photos of the boat, do you still go with those recommendations ?

Any preference as to 12 or 24 volts ?

Thanks again for your input !

[donradcliffe]

The 1000 watt windlass should be fine. If you go with 24v, you can save money on the cables from the battery to the windlass, which are expensive. I would go with the 5/8" line, or better 3/4". If the current anchor works, keep it. Using 10 meters of 3/8" chain is optional in sand, and you will have to deal with how to get the chain/shackles through the windlass. My guess is that the boat weighs about 25 tons.

[ti325v]

Hi Don..
Thanks very much. i think that settles it !

[cat man do]

Originally Posted by donradcliffe

The 1000 watt windlass should be fine.
My guess is that the boat weighs about 25 tons.

Really?
I have a Maxwell 1500 (1200w) windlass on a 8500kg (9.3 ton) boat and I thought that would be borderline, considering the anchor I recently purchased.

Personally, seeing as you will probably be getting one of the myriad of chinese made windlasses available, all possible claiming to lift more than they actually can and all very cheap in comparison to western branded (not necessarily manufactured) windlasses, if it was me, I would be getting the largest most powerful one you can get.

No one ever complained about being over winched when they really need it, same goes for the anchor.