Wood Backing Plate in My Sail Locker

[off-the-grid]

It's for 2 U-bolts that are going in my anchor locker to tie the bitter end to.

Should I wrap the wood in cloth, or just put a coat or two of epoxy on it?

[thinwater]

Originally Posted by grunzster

It's for 2 U-bolts that are going in my anchor locker to tie the bitter end to.

Should I wrap the wood in cloth, or just put a coat or two of epoxy on it?

You can get either pre-lam FRP or AL in small sheets through many supply houses, or you can get a small scrap from a fab shop.

There is no reason SS would not work - but it is hard to work and over kill.

[s/v Jedi]

Wrap it in cloth/epoxy so that the bolts can't be pulled through. Plywood wrapped in glass/epoxy doesn't rot, assuming the holes drilled are coated in epoxy too!

ciao!
Nick.

[off-the-grid]

Originally Posted by s/v Jedi

Wrap it in cloth/epoxy so that the bolts can't be pulled through. Plywood wrapped in glass/epoxy doesn't rot, assuming the holes drilled are coated in epoxy too!

ciao!
Nick.

That's the plan. And it's really high grade ply I'm using. Even better quality than most marine grade.

[Wotname]

Just out of interest, exactly what grade of ply is it?

[off-the-grid]

Originally Posted by Wotname

Just out of interest, exactly what grade of ply is it?

Not sure what it's called, but it's used in construction, I think for making molds for pouring concrete. Very thin plys, so it's really strong, and it has a coating on it already.

[GordMay]

Originally Posted by grunzster

Not sure what it's called, but it's used in construction, I think for making molds for pouring concrete. Very thin plys, so it's really strong, and it has a coating on it already.

I’ve never seen a very thin “concrete forming plywood” .

A typical plywood concrete forming panel consists of a substrate of five, seven, or nine cross-laminated plies, or layers, of wood veneer joined with waterproof adhesive under heat and pressure. The standard 4x8-foot panel is available in nominal thicknesses of 15/32, 1/2, 19/32, 5/8, 25/32, and 3/4 inch. It is strongest parallel to the face grain (normally in the 8-foot direction).

Specifications for the manufacture of plywood forming panels are detailed in a commercial standard titled "Voluntary Product Standard PS 1-07" published by the National Institute of Standards and Technology and the APA-The Engineered Wood Association. This standard outlines the species and grade of the wood veneers allowed as well as the type of waterproof adhesives used to ensure that the panels will meet expected strength and durability requirements.

PS 1-07 ➥ http://ts.nist.gov/Standards/Conform...oad/ps1-95.pdf

[off-the-grid]

I meant each layer is thin. therefore more layers, so stronger. I'm using 1/2 inch.

[sabray]

Sounds like medium density overlay or high density overlay. It has more layers then standard ac usually 7. Sometimes the overlay/coating is paper based. Should do fine for the application you are applying it to

[s/v Jedi]

Originally Posted by GordMay

Specifications for the manufacture of plywood forming panels are detailed in a commercial standard titled "Voluntary Product Standard PS 1-07" published by the National Institute of Standards and Technology and the APA-The Engineered Wood Association. This standard outlines the species and grade of the wood veneers allowed as well as the type of waterproof adhesives used to ensure that the panels will meet expected strength and durability requirements.

Ah, Gord, you always manage to make me smile ;-) Plywood and standards, they don't go together, unfortunately.

First, I know of no international standard. Every standard is national and every country has it's own, although sometimes, two bordering countries have standards that are different in name only.

The document you linked to is great. You learn a lot about plywood from it, but when you go and buy plywood, you will find it isn't much help. A good shop in the US will quickly tell you that the Dutch Bruynzeel plywood is the best there is, but it is grade "A/A" while you would expect grade "N/N". And it isn't even as simple as the US grade "N" equals Dutch grade "A". But the good shops all stock Bruynzeel.

If you are looking for solutions, browse this site: DUURZAAM BOUWEN MET BRUYNZEEL-MULTIPANEL
You will find plywood with up to 20 year (!!) warranty, or plywood with a balsa or foam core etc. etc. And I think it is all available worldwide.

ciao!
Nick.

[Wotname]

Oh goody, I have managed to drift the OP's thread into plywood standards - one of my favourite subjects.

Many years ago, I did read the British Standard and the Australian Standard for marine ply. I even understood some of it. I did work out there was some slight benefits with the Aussie standard although the rest of the world used to think the BS was best especially if it was Cabon or Bruynzeel.

However it seems that the various standards have been lowered over the decades to allow for the reduction of availability of quality species and grades of veneers; EXCEPT the Aussie Standard. The Australian manufactured marine ply ONLY uses one species (Hoop Pine) for all the veneers and while there may be equal quality in other parts of the world, the AS marine ply is very consistently excellent. Too bad you can't buy it .

It isn't the lightest by the way .

[Wotname]

Originally Posted by grunzster

Not sure what it's called, but it's used in construction, I think for making molds for pouring concrete. Very thin plys, so it's really strong, and it has a coating on it already.

Hmm, what I would call form ply and usually has one very thin but tough semi gloss plastic face (like a very thin formica finish).

Anyway sounds reasonable for your job, especially if you are of the school that believes the best product to use is the one you already have to hand and is readily available to you.