Re: Roof Material on 1995 320 SE
Reply #7 –
Bob,
Not sure what kind of repair you need to make, such as a crack, hole, delamination, etc. The roof is first a layer of gel coat, then some fiberglass reinforced polyester plastic, bonded to a 3/8" thick plywood panel. Next you will find some foam insulation in between square aluminum framing. On the ceiling side is another layer of wood and thin plastic. This is normally done upside down in a mold that has been treated with a release agent like a wax. First the gel coat is sprayed on then the FRP (usually with a chopper gun, a tool that chops the fiberglass into short strands and sprays the plastic resin together) is applied (could also be fiberglass mat which is slower, but gives a more even thickness}. If you have a crack and it has been there for awhile it is possible the plywood is rotten in which case that needs to be replaced. Normal procedure for a crack is to carefully grind away the area around the crack with a disk sander to create a feather edge at the crack, Then you can apply fiberglass mat and resin to build it back to original thickness. Sand to get it smooth and level with the original roofing. Apply gel coat and repeat the sanding process. In order to get the gel coat smooth and shiny you have to sand through all the grits up thru 2000 grit. Polyester resin is probably what you should use as it will stick to polyester, but not epoxy. Epoxy resin is stronger and will stick to polyester and itself. What I have said is just a start. Consult a book on polyester fiberglass repairs.
Since you are in British Columbia, there are probably some boat yards that will have experience doing fiberglass repairs and may be able to do the repair in case you think this might be a difficult job.
Topic: Roof Material on 1995 320 SE