Best way to cut fibreglass?

BellevilleMXZ

I need to trim a bit , as I bought a door to go where the crappy cooler opening was. I need to trim the edges a bit, whats the best way to do this?

Black_Diamond

A router is probably best. Will be messy. Tape the area with painters tape first, will help chipping of the gelcoat. 

reneechris14

X2 on the router,try to make some kind of fence or straight edge to help guide it.

LaRea

The cut will be concealed, right?  Just try to avoid creating sharp corners (like you'd get using a reciprocating saw).  Corners tend to concentrate stresses, and can lead to cracks later.  Cut the corners using a drill or router.

99270fv

I need to trim a bit , as I bought a door to go where the crappy cooler opening was. I need to trim the edges a bit, whats the best way to do this?

how much is a little bit? a sanding drum on a drill may work best

diggin2day1

Depending on how much you need to remove... I would use a jigsaw with a down-cutting blade(like a laminate blade) to reduce tear out. Masking tape all cutting areas and go to work. 

duane.mosley

BellevilleMXZ said:

I need to trim a bit , as I bought a door to go where the crappy cooler opening was. I need to trim the edges a bit, whats the best way to do this?

i did this to mine and i love it!

the door the i got from great lakes skipper matches great color wise and i only had to trim the top corners of the existing opening to get it to fit.

i used masking tape to put over the fiberglass to prevent splintering when you cut. i also used a fine scrolling blade with my jigsaw. the more teeth on the blade the better. put enough tape over the area so the the foot plate of your jigsaw doesn't scratch the gel coat. make your pencil marks on the tape and cut.


here is a link to a thread where i posted a picture of mine completed.

http://rinkerboats.vanillaforums.com/discussion/1875/hatch-doors-in-290ec-etc-where-to-find#latest

Michael T

Fine scrolling blade and if you still have any concerns use the old carpenter's trick - use a very sharp blade (like a box cutter) to pre-cut the area (scribing) so that if any gelcoat/fiberglass starts to splinter it will not run past the scribe. The line you pre-cut (scribe) should NOT be deep - just a surface cut to stop run away gel coat cracks/chips. We did this all the time when using very expensive exotic woods for carpentry and I did this with all of my gel coat cuts.

BellevilleMXZ

Thanks everyone!! I don't have a router, so ill see about a good blade for the jigsaw. Cant wait to get this installed, such a waste of space. I don't have to take a lot off, mostly the corners, as the original hole, the corners are quite rounded, and the door has sharp corners. Its all hidden also, behind the frame of the door.

Liberty44140

I just enlarged my speaker cutouts for larger woofers. As noted above i masking tapped and cut through the tape to prevent gelcoat issues. I used a reciprocating saw and it was aweful, in 4 holes I trashed two blades and had lots of smoke. Doubt a jig saw will be better but it will work, just have extra blades. Dremel may be better. 

jme097

I have always used a Dremel with a fiberglass cutting bit. Takes a little longer that a jigsaw but its nice and easy to handle to make fine cuts. I tape the whole area off with painters tape as well. Keeps the fiberglass from chipping

zaverin1

I will be doing that soon
need to make two 7 1/2 inch holes for 8 inch pioneer speakers that are coming 

zaverin1

Wanted to go with tower speakers but said screw all that wiring noise and went the easy route. It will have 6.5 and 8 on main deck 

jme097

I just cut in 2 JL 7.7's on my swim platform. Dremel tool is always my go to!

zaverin1

Cut in my 2 8 inch pioneers to match 6.5 pioneers 
ended up using a jig saw with fine tooth blade