Subwoofer install in panel covered in fabric

I am looking to install a 10" MTX Marine subwoofer, and the panel I have to install it in is carpeted on the back side, and vinyl on the front. I want to cut from the back side(carpet) but would like to only cut the round hole through the carpet, and wood, and not cut the vinyl. I want to pie cut the vinyl after, and wrap it round the hole to the carpet side. Does anyone have a good idea on how to do this? Type of cutter? I was thinking of a dremel or router. Anyone else have a better idea? Thank you in advance!

Re: Subwoofer install in panel covered in fabric

Cut the carpet with a very sharp box cutter or razor knife using a template cut from cardboard or styrofoam sheet. Cutting the hole in the wood is another issue. Typically a circle cutter would be used to cut smaller diameter holes but a drill mounted circle cutter that big is not practical (and possibly not even available). One method would be to scribe the circle on the back side of the panel. Then use a drill with a small bit (anything in the 3/16 inch range to drill holes around the inner side of the scribed line. Drill the holes as close together as possible. Then using a dremel or RotoZip tool, cut the webs between the drilled holes. A RotoZip tool could be used to cut the hole without drilling as well. Just a matter of what you have a available. Use a drum sander attachement for your drill to clean up the hole. All of this must be done without puncturing the vinyl of course. Once you have the hold, make the vinyl pie cuts and staple (stainless staples) them on the back side. I would also suggest that rather cutting a round hole for the speaker that you cut the carpet such the hole matches the overall shape of the speaker. Bolting the speaker to the panel with the carpet between the speaker flange and the panel may cause uneven pressure and possible warping of the speaker.

Re: Subwoofer install in panel covered in fabric

Thanks for the idea of drilling multiple holes around the perimeter of the hole. I never thought of that! I am planning on getting a RotoZip type tool.