G10 for windlass backer plate

[Rogerh]

I have a Jefferson 52 with the backer plate for the windlass rotted out. It was made from 3/4 inch plywood. It was suggested that I use G10 to make the new backer plate. Since G10 is so much stronger than plywood should I still use 3/4 inch G10 or should I use a different thickness. The plate is 12X12 inch. I have a 45 lbs anchor with 150 feet of 3/8 inch chain. I dont want to go back with wood because of the potential rott issues. I know I could epoxy it first but....
Thanks for your inputs.

 

[FF]

Plywood is flat, Steel is flat.

Should make a change over very easy.

Even with a steel plate I would use large washers to help spread the load.

ALL of the time when anchored load will be on the chain stopper , chain claw or deck cleats, nothing on the windlass.

But in attempting to beak loose an anchor that is fouled frequently requires the anchor to be brought up short and the boat to power up in an attempt to break it out.

Stopping the boat short frequently with the stuck anchor creates high loads.

Sure >next time< you will use a proper trip line and float ball,but most folks will accept very high loading in desperation not to wave By BY to a big $$$$$$ anchor.

 

[Nomad Willy]

My "backing" plate is on the foredeck. Not under but on top. The "plate" is 1 1/8th" plywood w 15 or so screws through the deck w fender washers under the 3/4" plywood and FG deck. It's about 2' square so the load is spread around a large area for a 30' boat. It's bedded in Dolphinite.

The small winch, center anchor cleat and OB mooring cleats all share the mounting plate and I have confidence in it's strength. It's exposed and subject to rain water, sea water and anchor chain but so far has held up well. Servicing or replacement should be relatively easy.

If I were Rodgerh I'd get a bigger and thicker backing plate of plywood.

 

[rwidman]

The problem with plywood seems to be rotting or delamination. I suppose if it was well sealed with epoxy including any holes drilled in it, there would be less chance of this happening.

The plywood transom of my Zodiac dinghy rotted through in just three years. I would have thought a boat would be designed to be waterproof but that's a whole other story.

 

[HopCar]

Wood rots
Steel rusts
G10 is expensive
Starboard, adhesives don't stick
Built up Fiberglass Pad, nasty overhead job
Aluminum?
Stainless steel?

All the backing pads on my boat are epoxy coated plywood. If I ever have to replace them, I'll use G10 but it's certainly not the only option.

 

[Nomad Willy]

My plywood pad was heavily coated w Linseed oil, turpentine and wood preservative. Was going to leave it at that but wanted to experiment and see if an extremely heavy coating of oil would help a top coating of varnish. With all the oil under water seems not to be able to get under the varnish. The varnish I used was McKloskie's gloss w Tung oil. Haven't tried the heavy oil under varnish on teak though.

On my Willard there was no backing plate under the bow cleat .. just fender washers. And the single cleat was rather small.

Heavy plywood under and on top of the deck seems the ultimate in strength to me. Won't bend or otherwise deform in shape and is stiff.

And of course it will delaminate and otherwise weather but is relatively easy and inexpensive to replace. Not heavy either.

But metal and plastic will hold up longer w/o maintenance.

 

[BruceK]

Here`s a pic of the glass over ply "box' on which the metal plate on which the windlass mounts. The metal plate extends well forward. There is a post underneath providing support for the windlass.These days there is a wood spacer between windlass and plate, necessitated by a new windlass motor fitted by the mfr Muir protruding below the windlass casing. It`s a sturdy arrangement now, when I acquired the boat the 'box" was failing generally and required total removal and rebuild

 

[HiDHo]

I used a sheet of 1/2" thick air craft grade aluminum beaded with 3M101 and starboard spacers between the windlass base and the aluminum.
Bill

 

[C lectric]

If you already have the piece of G10 then use it. Overkill is better than the alternate especially when you already own it.

 

[FlyWright]

If you already have the piece of G10 then use it. Overkill is better than the alternate especially when you already own it.

+1

If you don't already own it, try a local fabricator or steel shop. I was able to purchase scrap size pieces of stainless to make my top and backing plates. I had a local polishing shop buff a mirror finish on the top plate. There are 4 large nuts welded to the underside of the top plate with long 3/4 inch threaded studs which run from the top plate, through the deck and backing plate, and secured with oversize washers and locknuts.

I used approx 1/4x12x12 SS backing plate to replace the former wood backplate. IMO, the bigger the backing plate, the better.

 

[FF]

>Built up Fiberglass Pad, nasty overhead job<

Steel is built in a factory,

Plywood is built in a factory

Why would GRP need to be built in place?

Laying up a Sq ft or two of GRP to what ever thickness is desired is a snap .

Then cut and trim to fit , DONE, and it wont rust , rot or dissolve.

 

[Rogerh]

Great feedback and many ideas. I ordered the G10 yesterday because it was a good deal and I thought it might workout great. $33 for a 1ft X 1ft 3/4 inch plate. I will let you know how it goes. My only concern is the tooling of it. I read you need to use carbide blades and drills. The drill is no problem but a 5 1/4 inch carbide hole saw that may be a little tougher to find. Has anyone cut the stuff?

 

[HopCar]

FF, good point. You could make your own fiberglass sheet, then stick it up overhead.

Roger, for a hole that large you should be able to cut it with a jig saw. Carbide jig saw blades are fairly affordable.

 

[Nomad Willy]

Al,
I like your setup a lot. Quite compact (more so than mine to be sure) and I'm wondering what was there on the boat as manufactured? Looks like a lot of manufacturers just bolt this stuff to the deck. Speaking of decks how beefy is yours Al? And how is the deck fastened to the bow? As much as I like your typical setup for a trawler I don't think it's ideal. Seems your windlass is dependent on the attachment to the topsides. Side loads on the end of the pulpit could be double where the pulpit attaches to the railing. Seems to me mounting the whole works down lower flush on the deck w a hole in the bow for pulpit and anchor would be somewhat more desirable.
My friend Ed out of Craig AK mounted his bow roller assembly flat on the deck and through the bow topsides. No extended bow pulpit is required and the overall length of the boat is minimized. The bronze bowpiece serves no purpose that I know of at this time. Notice he has only about 30' of chain and the bulk of his rode is nylon. The big (65lb) anchor is common in AK.

I prefer Bruce K's setup. Short pulpit and little difference in winch height and pulpit height. Everything seems to be in just the right place and looks strong. Nothing appears to be in excess but all looks well up to the job.

With these bow pulpits I wonder what the weak link is? I attach my bow roller assembly w only two 1/4" bolts so if it's torn off the bow the bolts (hopefully) fail and leave the more important parts of the bow intact. The anchor line would then lay over the rail and perform almost as well as if it were in it's normal place.

If I ever get time I think I'll follow Ed's lead. Not sure my laminating skills are up to the hole in the bow though. If I could skillfully cut the hole though perhaps it wouldn't take long for a skilled laminator to wrap it up.

 

[FlyWright]

Eric, my boat came with the pulpit as you see it with a fixed roller and a power winch mounted on the deck. I added the SS plate, windlass, self-deploying anchor roller, chain tube, cleat, safety cable and wash down hose. The pulpit is a hollow box, but there was no chain tube...all the chain lied upon the deck and had to he hand-fed into the anchor locker. You can see part of the cap on the anchor rode pass through. (It's no longer used.)

Here's a pic just before another anchor retrieval after numerous anchorings while fishing. This is why I like the washdown system.

I don't know how the deck is attached, but all the Californians I've seen have similar anchor pulpits. The decks are very stout, as is the entire boat. I remember cutting the deck hole for the chain tube and being impressed with the thickness and apparent strength. I don't remember the exact thickness, but it's in the neighborhood of 3 inches thick. If I ever find that plug I removed, I'll post back on its actual thickness.

This one has lasted 37 years and is still there. I've never seen a Californian without one or with it torn off. Are there more secure ways to fasten it? No doubt there are. Is this sufficient for the loads encountered? Apparently it is.

 

[Al]

Eric- Sent you a PM last evening. Hope it came through if not let me know. Al

 

[FF]

Not everyone would consider a windlass holding the load while anchored is a great idea , if it is not just for a fishing spot.

Over night or God forbid in a storm it could get iffy.

 

[ksanders]

We have this stuff we use in Alaska called All Weather Wood.

I'm sure they sell it in the lower 48 states as well. Its kinda green treated wood, or treated plywood.

The stuff will not rot. It will not delaminate. It is a forever product.

I've used All Weather Wood for all kinds of outdoor, and boat projects for decades and it works great.

If I were doing a backer plate on my boat, and I've done a bunch of them, I'd use 3/4" All Weather Wood and be done with it. Bed it with 5200 and it will forever be a part of your boat.

 

[Nomad Willy]

Ken,
"All Weather Wood" sounds like a miracle. I'll look into it.

But I'll pass on the 5200 there. I want to be able to take things apart.
Polphinite for me and disassembly every few years (5-10).

 

[kthoennes]

Just replaced mine with starboard. I read the post above about adhesives not sticking to it, but what would you glue to a windlass base plate anyway? I did run a bead of sikaflex under the edges and around the motor shaft and hawser holes, but that's a sandwich of course, just for sealing. I know starboard isn't the stiffest stuff though, a big chunk of beefy stainless might be better for heavy use. I'm just on the Missouri River (for now).

 

[Nomad Willy]

kthoennes,
I use Sika Flex under my cleats and capstan. But Dolphinite under the mounting plate. One not so good thing about the Dolphinite is that it oozes out for a long time as it never sets. I just scrape or scoop it up when I see it.