Plywood

[guydickinson]

Do you think its always a good idea to use marine ply for use in a boat in sheltered places where it might get damp sometimes but mostly dry (ie storage spaces)? Or will other grades do? Not always easy to get - marine ply - is it?!

 

[Drascomber]

For use in the cabin I use what my local timber merchant sells as "marine ply". It is durable but has thin outer veneers and is awfull to work without getting crumbly edges - but it is cheap.

For use on deck (or if I was building a hull) I use the real McCoy from Robbins at 4 times the price.

 

[VicS]

I guess you are thinking about WBP exterior ply as an alternative to marine ply.

I once used exterior ply from a timber merchant to make the box of a camping trailer. Absolutely no problems with it.

Some years later I decided to make a deeper box. Again using exterior ply but this time I shopped around for a low price. Disaster it delaminates if it stays wet for long.

I also built small dinghy using exterior ply. Still in good nick 30 years later.

Click: I reckon that if you use exterior ply you must be sure it is good stuff. Buy cheap and you get the rubbish I got for my deeper camping trailer box

 

[guydickinson]

Thanks all - well I am really thinking of lining the lockers (esp floors) where the previous wood has deteriorated - no idea what that was! Earlier I checked Robbins who I know are good and who I've dealt with before. One sheet of 8x4 12mm marine ply is about £40 - but its £22 to deliver! (£25 for 2 sheets and so on). Hence the question really.

 

[PCUK]

WBP is fine for interior use (Note Vics comments re quality!)
Marine for hulls etc.
If you further encapsulate the ply with GRP you should have no further problems.

 

[oldsaltoz]

G'day Guy,

The primary differance betweem marine and construction ply is that the latter will have voids caused by knots in the original timber, marine ply is made from the core timber so no imperfections. That's the therory anyway.

Construction ply is fine if properly treated after cutting to size. We normaly use epoxy, a bit of an overkill but never fails. We thin the epoxy resin with Methylated Spirits, 30% by weight or volume, makes it thin and ensures good penetration; the edges need close attention as the end grain sucks up lots.

Hope this helps.

Avagoodweekend......

 

[Heckler]

bit of thread drift, but, do you thin after adding catalyst or before?
Ta in anticipation
Stu

 

[smeaks]

what a cracking dinghy!

 

[Tranona]

Suggest you try Howells in Cobbs Quay. They stock a wide range of Ply and no delivery charges.

 

[guydickinson]

Many thanks Oldsaltoz - by the way, which part of the East coast are you in Oz? Sounds great.

 

[oldsaltoz]

Mix epoxy and hardener then add Metho.

Avagoodweekend......

 

[oldsaltoz]

G'day Guy,

Southern end of the Whitsunday Island group.


Here


But our Cat is in Cairns, so I try to work a 20-10 roster, 20 days at work and 10 off, spent in Cairns, sailing the local reef and sand kays as well the odd visit to the resorts and other Islands.

Here

Avagoodweekend......

 

[S2Jimlad]

Have you thought about starting a post to see if anyone else wants any? You could combine the shipping then. I did this when I re-built a wooden Silhouette. Saved a fortune.

 

[Topcat47]

You really have to watch with WBP. Looking for half and quarter sheets, I was utterly dismayed with the quality of timber I found at B&Q & Wickes. Delamination was particularly poor in the quarter sheets, where in some cases laminates were barely glued together at all. The staff shruged their shoulders in each case although B&Q were particularly helpful in locating a good sheet for me. I now buy full sheets from a local timber merchant and have him cut them down for me. he does find large voids from time to time, but I don't get the problem, his supplier does.

 

[tangomoon]

Three coats of epoxy should keep the water away from the ply