fiberglass curb

I have a new project where I am wanting to build a curb,frame or ring if you will to set a console, I will be glassing it to the boats deck ten laminating some 3/16 alum plate in the curb to be tapped for mech fasteners , I have a template of the shape and I was going to us a Bldg, grade foam called Tuff R as the shape, The glass will be the strength not the foam The foam is simply a male mold,, Please give me your thoughs Thanks

 

If I understand correctly it's a vertical flange? I think you can just use adhesives for that plate but SS screws and aluminum plate, will that be a problem? You can also embed threaded inserts or just use a core of high density Coosa Board and screw right to that with 5200. That is all I can offer.

 

Not a fan of the ss/alum idea just because I hate how aluminum and ss work together, galling, galvanics, etc. Plywood would be better or high density foam. If you use the plywood, turn it sideways and you can even double it up, but fully encapsulate it. Now, you didn't say how big the console is, so that is the only caveat. If the console is massive, I might take a different approach.

 

The boat is a 15' skiff, and the console will have a mini coffin box I like the above suggestions My though in using the low density foam to form a male mold and leave the foam in place I like the idea of a threaded insert,, just how to do it is the question for me,, Thanks Folks

 

You can mix foams too, high density in any crush, screw locations, low density for the rest to keep it light.

 

Personally, I'd use some screws to hold it in place and I'd put it into a cleat or angle iron shape with the angle open to the inside. You can make the curb strong with a fillet on the inside (after dry fit) and use low den on the bottom and hi den on the sides (jorgepease's idea), or ply and ply. Then a simple screw will be easiest for attaching the console. Maybe like #10 or #12. If you use a decorative washer and measured the locations, it'd look great. Then, if you ever have any issue, the screws are easily removed and the console lifted up. You can seal it at the bottom with 5200 if you want and knife cut if needed for removal. SS screws seem to shear less than others and a #12 is really strong.