Cushion and Seat Rebuild

[76SeaRay]

I plan to use either marine plywood or exterior plywood for the backer wood. Before covering the wood with either foam and fabric (inside the V Berth) or foam and Marine Vinyl (exposed to weather), is it better to leave the wood bare, cover it with a polyurethane paint or cover it with a layer of 3/4 oz CSM? If paint or CSM, is it best to do both the top and bottom of the wood?

 

[Chris1956]

Use dry PT plywood and cover it with spar urethane or polyester resin. Stainless steel screws and Stainless steel staples as well.

 

[Scott Danforth]

Todays boats use HDPE (starboard) if the substrate needs to be structural or PVC proboard if it does not need to be structural. About the same cost per sheet as Marine ply

 

[76SeaRay]

The old cushions use just cheap exterior plywood. I haven't found a source close by for starboard. How do you attach upholstery to starboard? It doesn't look like it would accept staples.

 

[Chris1956]

Just seal the plywood well with one of the coatings recommended. It will last the length of the vinyl's life. My '98 Seaswirl has some kind of 1/4 plastic for the bow backrest cushions. You can staple to it, and it lasts forever, but is not structural. The structural components are plywood.

 

[Scott Danforth]

The old cushions use just cheap exterior plywood. I haven't found a source close by for starboard. How do you attach upholstery to starboard? It doesn't look like it would accept staples.

it takes staples very easy.

if you look at @tpenfield build, his upholstry is all PVC

 

[tpenfield]

Most newer boats use HDPE (i.e. StarBoard) for upholstery frames and backing. You can certainly use plywood, but you should treat it with a wood sealer of some sort (search Old Timer's Wood Sealant) before you mount foam and upholstery covering to it.

 

[76SeaRay]

The design of the boat means the seat cushions at the stern and in the V Berth will need to be structural. I will try again to find a star board supplier in my area so I can get a physical sample to play with, otherwise I will likely go with marine plywood and a coating as mentioned. Thanks..