Marine Plywood & Bulkheads - SailNet Community

   Search Sailnet:

 forums  store  


Quick Menu
Forums           
Articles          
Galleries        
Boat Reviews  
Classifieds     
Search SailNet 
Boat Search (new)

Shop the
SailNet Store
Anchor Locker
Boatbuilding & Repair
Charts
Clothing
Electrical
Electronics
Engine
Hatches and Portlights
Interior And Galley
Maintenance
Marine Electronics
Navigation
Other Items
Plumbing and Pumps
Rigging
Safety
Sailing Hardware
Trailer & Watersports
Clearance Items

Advertise Here






Go Back   SailNet Community > On Board > Gear & Maintenance
 Not a Member? 


Like Tree2Likes
Reply
 
LinkBack Thread Tools
  #1  
Old 03-29-2011
Beersmith's Avatar
Sailing to surf
 
Join Date: Nov 2008
Location: St. Augustine, FL
Posts: 208
Thanks: 1
Thanked 0 Times in 0 Posts
Rep Power: 6
Beersmith is on a distinguished road
Marine Plywood & Bulkheads

I am needing to replace many of Windsong's bulkheads and cabinets due to a lot of rot from years of neglected leaks.

I am having trouble finding a local supplier of marine plywood, and am not too excited about the price of what I have seen out there. I plan on using marine plywood, so don't get on my case too hard...I'd just like to see if the alternatives are suitable for above the waterline, and in theory, dry work.

So, must I use marine plywood for interior cabinetry and bulkheads? I plan on covering each piece of wood I use with epoxy to seal it up and prevent water intrusion, but I know that isn't 100% effective in the long run. I'd love to be able to save some cash and time by not having to find and use marine grade plywood, but if the argument for using it is compelling I will stick to that route.

(and before some smart guy says I should worry about the leaks first...yes, I've got that covered )
__________________
My boat rebuild/sailing blog:
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Reply With Quote Share with Facebook
  #2  
Old 03-29-2011
SlowButSteady's Avatar
Senior Slacker
 
Join Date: Feb 2010
Location: SoCal
Posts: 4,223
Thanks: 0
Thanked 17 Times in 15 Posts
Rep Power: 5
SlowButSteady is on a distinguished road
Supposedly, marine-grade and exterior-grade plywood used the same adhesives. The difference is that marine-grade plywood has no interior voids, while for exterior-grade plywood a certain percentage of "void space" is allowed. I would think that a good exterior-grade plywood, with a couple-three of layers of penetrating epoxy on all surfaces (maybe a layer or two extra along the edges) would be as strong and rot-resistant as you can get. Slap a nice-looking treatment (wood "door skin", Formica, or whatever) on the exposed surfaces and it would look like a million bucks.

The "You're-full-of-crap" posts may commence ...... now.
__________________
Never forget them. Do something to prevent it from happening again.
Charlotte Bacon, Daniel Barden, Rachel Davino, Olivia Josephine Gay, Ana M. Marquez-Greene, Dylan Hockley, Dawn Hochsprung, Madeleine F. Hsu, Catherine V. Hubbard, Chase Kowalski, Jesse Lewis, James Mattioli , Grace McDonnell, Anne Marie Murphy, Emilie Parker, Jack Pinto, Noah Pozner, Caroline Previdi, Jessica Rekos, Avielle Richman, Lauren Rousseau, Mary Sherlach, Victoria Soto, Benjamin Wheeler, Allison N. Wyatt

Last edited by SlowButSteady; 03-29-2011 at 12:25 PM.
Reply With Quote Share with Facebook
  #3  
Old 03-29-2011
LandLocked66c's Avatar
Sunsets and Warm Beer....
 
Join Date: Dec 2009
Location: The Bottom of a Pint Glass...
Posts: 2,111
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 5
LandLocked66c is on a distinguished road
I replaced my sole with standard plywood, sealed and potted of course.

Marine grade also has more/thinner ply which allows it to be stronger and lighter. Some say it will also rot slower because of having more ply. Boats were built before marine grade was around so I care not what others say about using/not using it. If it stays dry it should be more than adequate for a bulkhead.
__________________
1971 23' Oday Pop Top
S/V Frida

You can't steer a boat that isn't moving? Just like a life - P. Lutus
Reply With Quote Share with Facebook
  #4  
Old 03-29-2011
tommays's Avatar
Senior Member
 
Join Date: Sep 2008
Posts: 4,235
Thanks: 1
Thanked 24 Times in 24 Posts
Rep Power: 6
tommays will become famous soon enough
I think your will find the marine plywood more stable due the larger amount of plys which is how they also make furniture grade ply before applying the veneer

I find SOME exterior-grade plywood is unhappy and try's to imitate a potato chip shape unless its nailed to house
__________________
1970 Cal 29 Sea Fever

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

1981 J24 Tangent 2930
Tommays
Northport NY


If a dirty bottom slows you down what do you think it does to your boat
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Reply With Quote Share with Facebook
  #5  
Old 03-29-2011
Senior Member
 
Join Date: May 2007
Posts: 602
Thanks: 0
Thanked 1 Time in 1 Post
Rep Power: 8
Siamese is on a distinguished road
If regular plywood's okay, why not just use OSB?
Reply With Quote Share with Facebook
  #6  
Old 03-29-2011
LandLocked66c's Avatar
Sunsets and Warm Beer....
 
Join Date: Dec 2009
Location: The Bottom of a Pint Glass...
Posts: 2,111
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 5
LandLocked66c is on a distinguished road
Quote:
Originally Posted by Siamese View Post
If regular plywood's okay, why not just use OSB?
I believe Chrysler boats did, didn't they?

Or was that press board?


I can tell you that my 1970 Oday does not have marine grade plywood at all! Nor did it ever.
__________________
1971 23' Oday Pop Top
S/V Frida

You can't steer a boat that isn't moving? Just like a life - P. Lutus
Reply With Quote Share with Facebook
  #7  
Old 03-29-2011
JohnRPollard's Avatar
Moderator
 
Join Date: Mar 2007
Location: Chesapeake
Posts: 5,680
Thanks: 0
Thanked 2 Times in 2 Posts
Rep Power: 10
JohnRPollard is a jewel in the rough JohnRPollard is a jewel in the rough JohnRPollard is a jewel in the rough
Hi Beeresmith,

I would really encourage you to stick with marine ply. Bulkheads are structural. BS 1088 marine ply will stand-up better, due to better laminate schedule and minimal voids.

I have several sources of marine ply from whom I purchase. If you do not need a teak veneer, you can get Sapele or Okoume from Chesapeake Light Craft. While not local to you, they are top notch, very good to work with and are experienced at shipping anywhere.

If you would like to get a teak veneer -- which usually looks very nice on boats -- you can order sheets from Buck Woodcraft right there in Marathon FL. I've been very happy with the teak veneers I've received from them -- which I've used for cabinetry.

Yes, it's expensive compared to regular ply. But the real cost of most jobs is the time and effort. It rarely makes good sense to skimp on the supplies.
__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Pacific Seacraft Crealock 31 #62

NEVER CALLS CRUISINGDAD BACK....CAN"T TAKE THE ACCENT

Last edited by JohnRPollard; 03-29-2011 at 04:03 PM.
Reply With Quote Share with Facebook
  #8  
Old 03-29-2011
Senior Member
 
Join Date: Dec 2010
Location: So.Md
Posts: 231
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 4
AirborneSF is on a distinguished road
PT boats were built from marine plywood, must be good for something? .02
Reply With Quote Share with Facebook
  #9  
Old 03-29-2011
mitiempo's Avatar
Senior Member
 
Join Date: Sep 2008
Location: Victoria B.C. Canada
Posts: 7,071
Thanks: 0
Thanked 68 Times in 59 Posts
Rep Power: 7
mitiempo will become famous soon enough mitiempo will become famous soon enough
If it is for cabinets and not bulkheads exterior ply is ok. It would depend on the finish you want. Most exterior grade ply is fir and if you are going to paint it is very hard to get a good finish on fir. But if you are going to use a laminate no problem. For bulkheads marine ply is worth the extra. More plies, more stable, will take a paint finish well if not fir. Marine ply is not lighter though.
__________________
Brian
Living aboard in Victoria Harbour
Reply With Quote Share with Facebook
  #10  
Old 03-29-2011
Senior Member
 
Join Date: Jul 2006
Location: Corpus Christi, Tx
Posts: 962
Thanks: 14
Thanked 19 Times in 18 Posts
Rep Power: 9
ccriders is on a distinguished road
Exterior plywood is never going to look good unless covered with formica or some other such product. So factor that cost and time into the cost calculation. Most exterior plywood is of atrocious quality, the outer skins so rough and porous you would have to sand half of it away to get a level of smoothness for any kind of finish material. And with patches and voids all over the sheet you can never be confident that the area around the chainplate bolts is good solid material. Finally, most of it never lays flat and will drive you crazy.
There are reasons it is so cheap.
John
Reply With Quote Share with Facebook
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

 
Posting Rules
You may post new threads
You may post replies
You may post attachments
You may edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Marine plywood gg30citation Gear & Maintenance 6 01-26-2008 10:23 AM
Marine plywood gg30citation Gear & Maintenance 2 01-25-2008 10:32 PM
Hunt for Marine Plywood landlockvasailor Gear & Maintenance 11 08-30-2007 06:01 AM
Marine plywood VS. pressure treated (wolmanized) plywood duffer1960 Gear & Maintenance 8 03-03-2006 12:12 AM
MARINE PLYWOOD drynoc Gear & Maintenance 3 01-30-2004 08:14 AM


All times are GMT -4. The time now is 02:45 AM.

Add to My Yahoo!         
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
(c) Marine.com LLC 2000-2012

The SailNet.com store is owned and operated by a company independent of the SailNet.com forum. You are now leaving the SailNet forum. Click OK to continue or Cancel to return to the SailNet forum.