Coffin lid rebuild

[CDUX]

Good morning, I'm Fred, I boat in So. Maine, on a '82 22' CC which has been in the family since '84, and has seen its share of neglect over those years.  I'm glad to have come across this site from iboats, found wealth of info here.

Presently I'm re-coring my coffin lid over the tank.  I noticed while removing the old core that it was made up of 3 8" wide pieces of ply.  Any reason to replace in kind or would one sheet cut to size do?  Also is marine ply necessary if I'm completely encasing w/ glass? The original only had one sheet of porous woven mat on the under side.

BTW anyone know or recommend what size ply to get, after pulling off the under coat the core was too far gone to get a accurate measurement on thickness.

Thanks
Fred

[kaptainkoz]

I would think the multiple pieces was a cost saving move on Aquasports part. If it were me I would replace with a single piece as thick as I could fit in the space provided. Measure as best you can and at least go with the same. If you dont want to spring for marine grade then at least use an exterior grade ply. It has to be made with a waterproof glue regardless of being encased or not. Water will find its way eventually. In that application personally I would use an exterior ply and be done with it. be careful of its orientation on the lid. Remember that whatever you put in may have to clear the rim/frame of the coffin. I also supported the center of the coffin when I put mine together. I carefully dremeled a channel in the coffin and 5200'd in a piece of hardwood.

[slvrlng]

Welcome! If you look down the threads on this section wingtime has a most excellent rebuild on his lid. Its the one under"another fuel tank". Like I told him I'm just glad mine is solid for now!

[wingtime]

Fred,

I used 3/8" Okoume marine plywood that meets British Standard 1088.  Do a search and you will find out all you need to know about this wood.  I believe my core was about 29" x 82".  I used almost 2 gallons of resin on my lid.

[CDUX]

Yeah I read thru his posts the other day before I removed the lid.  Unfortuntally my tank is in a similar condition to his and after seeing his custom made tank he post the other night, I got some calls out to a few buddies down at the shipyard. Maybe I can get a tank for the cost of materials and few 30 packs.

Kap
Thanks for the pix and the thoughts. I think I'll put the tank back in and see what I can get away w/.

[wingtime]

On the cost of the wood core.  The 3/8 Okoume was $57.00 for a 4 x 8 sheet from a local plywood company.  I probably had about $125-150 in glass.  I'm also planing on glassing in a couple of wood supports on the bottom of the lid to beef it up since a 29" wide unsupported span is a tad wide in my book.

[billfish33]

my lid also has to be redone soon.
I have a gal of mas epoxy resin,as well as a 1/2 gal of med hardener with a 2 quarts of filler,
I still need the fiberglass mat,as well as the plywood.

I may do this within the next few weeks.