Engine hatch bend fix

[raptorheli2]

Hey all,

I need to fix a fibreglass engine cover on a stern drive that is bending in the middle. You need to walk over it to gain access to the boat so no surprise.

I'm in middle of replacing the sound proofing so now is time to fix this.

I'm wondering what type of wood is best to use to do it? I've already got west systems epoxy/glass here.

 

[RunAgroundHard]

I doubt it matters. I assume the wood will be used as a former, then the fibre glass moulded over to creat a shape that stiffens the engine cover. For example, some boats have foam formers under the fibre glassed ribs. The stiffness and strength comes from the shape created by the fibreglass, not the wood.

Basically, you can use anything to make the shape, as once the epoxy has set, the shape is what will matter to create the stiffness you need.

 

[reallycoliholic]

I read this a different way in that you want the wood to stay there rather than being a mould? In that case I'd go with 3/4 ply, ideally marine ply but since it's not getting too wet, I'd be happy with exterior grade. Stick it to the existing cover with epoxy and laminate it in with two or three coats of epoxy and glass fibre.

 

[Stemar]

I did a similar job on the Lazarette cover of my Snapdragon, which was about 2' square. I used a couple of pieces of roughly 20mm square treated pine (offcuts of gravel board) because it was what I had. I covered it with several layers of GRP, and it was as good as new when I sold the boat 15 years later.

As RAH says, it really doesn't matter what you use, as it's the box shape of the GRP that gives the stiffness, and should be lighter and at least as rigid as a layer of ply. If you go down the ply route, I would use marine ply if at all possible, because it WILL get wet sooner or later.

 

[Refueler]

There are many materials that can do this job ...

Ply sheet to create a second layer - then glassed over.

Wood strakes to create stiffeners - glassed over.

My favourite as used to strengthen Centaur bilge keels - is Glass Rope .... you can get this in various diameters and it is basically glass matt in rope form ... so when you apply - you apply it wetted out ... and then add matt to finish and blend it in. No rot to eventually sort.

 

[rogerthebodger]

You can use a roll of paper to create a ridge across the center on the underside and glass over it with epoxy and glass CSM