Could I replace this failed plywood with plastic?

[salar]

This gap in the side mouldings of my GRP cruiser has a rope locker made with a piece of ply coated in flo-coat. As you can see it has rotted! Rather than replace like for like, I am toying with the idea of making a replacement panel with GRP (time consuming and expensive in materials) or a cut sheet of plastic. There are many sheet plastics available, cut to size by the supplier. Has anyone any experience of using sheet plastic for this type of application and if so what type - HIP? I'm thinking 6mm would do the job. If so, what glue would be best to fasten to GRP? Thanks in anticipatio

 

[V1701]

Whatever you use if it's closed and damp stuff goes it it it'll always be damp in there, maybe a few drain/breathing holes would help?

 

[salar]

Whatever you use if it's closed and damp stuff goes it it it'll always be damp in there, maybe a few drain/breathing holes would help?

It does have drain holes actually - the problem is that is was very badly made by a previous owner and is right by a wet area from the wheelhouse roof and side deck. That's why I want to avoid replacing with ply covered with csm again because water is bound to get into the core. I'm hoping the right kind of plastic sheet will be easier than making a GRP sheet myself.

 

[Stemar]

It isn't original, so it won't be structural. Make it of whatever you want, but I'd put a "floor" in it sloped towards drain holes or anything left in it is going to get pretty manky.

 

[Fantasie 19]

Having had my second cockpit locker lid fail for the same kind of reason (and this was ply with two coats of epoxy) I'm thinking of doing the same thing.. interested in the suggestions...

 

[bedouin]

There is a material called "poly-wood" that comes in sheets and is a replacement for marine ply in situations like that. No cheap

I would have thought many of the plastic panels (e.g. the foam cored ones) would do the job there as well and be a much cheaper option

 

[steveallan]

Use UPVC sheet

 

[Ian_Rob]

The gas locker door on the Dufour 365 is an Acetal (Delrin ) panel. I think a 4mm panel would bend to the curve you have and you should be able to fairly easily cut it to the correct shape using a router. I would make a thin MDF template and use a router bush to follow the outline. The same template could be used to cut the round cornered opening. If care is taken with the preparation of the template you can achieve a very professional result. A problem will be the junction between the panel and the sides but this could be pointed with mastic - possibly rebating the edge of the panel to better achieve this.

PS check the flexibility to ensure that 4mm will bend over the length. 3mm and lesser thicknesses are available.

 

[sur-la-mer]

You can buy fibreglass sheets in various thicknesses. Do a proper job matting into place and gelcoat and it'll match and last as long as the rest of the boat.

 

[Ian_Rob]

You can buy fibreglass sheets in various thicknesses. Do a proper job matting into place and gelcoat and it'll match and last as long as the rest of the boat.

Must admit that I am inclined to agree...

 

[Snoopy463]

The material used for house facias and soffits could be used. Easily cut and stuck, designed to be wet most of the time in our climate. Comes in widths of at least 18”. Cheap especially if you have a neighbour having replacement windows.

 

[rogerthebodger]

I have used this for various boat / home projects

FOAMALITE® X-press - Maizey Plastics

Or this if you need thicker.

M-Foam Architectural | PVC Foamboard | Solid PVC Material

Should be available in the UK

 

[V1701]

I have used this for various boat / home projects

FOAMALITE® X-press - Maizey Plastics

Or this if you need thicker.

M-Foam Architectural | PVC Foamboard | Solid PVC Material

Should be available in the UK

King Starboard is the same thing as well I think, I don't know of anywhere that it's available in UK. I was looking at it as a possible material for making a hard sprayhood...

 

[salar]

I have used this for various boat / home projects

FOAMALITE® X-press - Maizey Plastics

That's given me an idea....I have a couple of sheets of something very similar I'm using in my studio. Do you think it would be strong enough, and what do you bond it with?

 

[rogerthebodger]

That's given me an idea....I have a couple of sheets of something very similar I'm using in my studio. Do you think it would be strong enough, and what do you bond it with?

Strength depends on the thickness and unsupported panels. 10mm would I think be ok.

I glue it with PVC weld the same used for PVC electrical conduit

 

[salar]

For those that are following this thread - thanks for all the replies! I have sourced a couple of metres of 400mm wide UPVC soffit which I will be using to replace the plywood. Thanks to the Nexdoor app I was able to get exactly what I needed with 24 hours, for free, from someone in the next village. When it's done, if I think it is presentable enough I'll share a photo.

 

[salar]

As there were several folk following this thread I thought you might like to see the outcome. I had a cubbyhole with a ply coveraing that had completey rotted. I stripped it out (carefully, avoiding wrecking the teak-effecr deck) and cut to shape two new locker sides from a scrap piece of 400mm UPVC soffit. I was able to use the rounded edge flange of the soffit as the corner by routing a mating edge on the side panel. The cut edge is a bit softer than the polished face so I pigmented some two-pack epoxy and painted the cut edges with that. It was all glued and sealed into place with Evo-stik Sticks Like Sh*t. Final job is to put an 8mm floor piece in the bottom to raise it to the level of the surrounding deck so it drains out - not like before! Total cost abot £7 for the glue.

 

[sogood]

That's a sweet looking job. Well done!

 

[Stemar]

 

[PCUK]

A professional job at an amateur price! What could be better?