How to make sub-hatch with bubble?

[dana]

so basically im putting a sub hatch on my mean machine. the problem is i need it to bubble up where the motor is. i bought some 2 mm black pvc sheet, and my plan was to heat the center and push a bubble into it. well it was a little tougher than i thought... i got it to bubble but torn a hole in it doing so. now i could just lay fiberglass over it and go with it, but it looks so ugly now. i just want some ideas on what i can do. I was thinking to just cut a hole in the sheet and use an rc airplane cowel hatch and glue it over the hole. thats all i came up with. i do want it to look nice like the rest of the build so far, so giving it a finished look would be nice. thanks, Dana

[T Nissen]

The method that I have used for both primary and sub hatches is to cut to size whatever material you are using for the base of the hatch (ply, abs). Then shape a piece of styrofoam for your"bubble" and glue it in position on top of your hatch base. Next apply epoxy/finishing resin and fiberglass cloth over the "bubble" and overlap the base by about 3/4". After the epoxy has cured cut out the base on the bottom side where the styrofoam is. Take a lighter and melt out the foam. That's all there is to it. I'm sure there are other ways to do it but this is my method and it works great. I attached a few examples that I made for some of my boats. One is a primary hatch and the other was a sub for a hydro. Hope this helps!

[Alexgar]

thats a great idea i use gardening foam and vasaline with fg resin

[Alexgar]

came up with this after trying to build a rail dragster right when bl motors cane our, wasted alot of fg resin and it never worked out but taught me the basics of fg