How to cut hole(s) for cup holders?

[tmh]

As one of my MANY winter boat upgrades, I plan on adding a few cup holders in the bow section of my boat. If i am cutting into the top of the fiberglass - say in front of the winshield where there is a flat spot -, how would I do it to reduce the chance of spidering of the gelcoat/fiberglass? I'd say the hole would be 2-3" diameter.

Do I drill a starter hole then use a Sabre saw to cut the hole? Certain type blade for fiberglass?

Also, I thought I'd use 3M 4200 to secure the cup holder in place - is that the way to go?

Thanks.

 

[Zamboni]

Re: How to cut hole(s) for cup holders?

After ensuring theres nothing behind the fiberglass your cutting use the proper size hole saw designed for fiberglass. There are brands with a rake angle on the teeth that won't chip glass or start those spider webs. I always go around with dremel sanding wheel after to make sure its clean with no cracks that will spread out from the hole.

Just sit the cupholders in hole-no epoxy....they collect a lot of crap so nice to remove them for cleaning and to replace if they crack/discolour.

 

[Mark42]

Re: How to cut hole(s) for cup holders?

Just to add to what Zamboni wrote, you can use a regular hole saw but they get expensive in larger sizes. Fiberglass will dull the common hole saw quickly. Actually, cutting fiberglass dulls any saw quickly. So either buy a cheap hole saw and toss it when done, or get an expensive one that will be usefull afterwards.

 

[strizzy]

Re: How to cut hole(s) for cup holders?

Also, never hurts to tape where your going to be cutting. But when the cutting, or drilling in general is done, its a good idea to chamfer the edges. You might want to add just a little sealent of some kind (4200 might be a bit much if you want to take them out, but if not then they should be fine), sometimes going down the road or water will cause things to take flight...

 

[tmh]

Re: How to cut hole(s) for cup holders?

A hole saw, OK even easier I guess. Thanks.

Good advice on not epoxying the cup holders in - cleaning/replacing....duhhh....should have thought of that. I may use something to hold them in place, but not a permanent epoxy.

Thanks again. The kidswill be glad to have cup holders in the bow to spill their sodas from!

 

[kalla man]

Re: How to cut hole(s) for cup holders?

just to add an extra bit of advice... If you run the hole saw in reverse first to score the top of the glass it helps to prevent any chipping of the glass/gel.~~~~~~~~~~~~~~~~~
THE PROJECT.......
s99.photobucket.com/albums/l309/kallaman/

 

[Boomyal]

Re: How to cut hole(s) for cup holders?

Fiberglass will dull the common hole saw quickly. Actually, cutting fiberglass dulls any saw quickly.

You got that right Mark. When I needed to cut down the length of my BeachCraft fiberglass doghouse, I thought I need to get a fine tooth saw blade to keep from splintering the fiberglass. I bought a 60 tpi blade for my Makita battery powered saw. I made about half the cut with great effort. The teeth were worn round.

I put on my somewhat dull 24 tpi carbide blade and sliced thru the rest of it without a hitch. I did use duct tape on both counts.

I just tossed that $9.00 60 tpi blade in the trash after that. I'm still using that somewhat dull carbide blade.

 

[ondarvr]

Re: How to cut hole(s) for cup holders?

You can get grit edge blades for each type, they last a long time and cut well and the sabre saw blades are easy to find.
A dull hole saw will cut a clean hole, and running a sharp one backwards to start the hole works well. Sharp hole saws tend to grab and jump out of the pilot hole, so be careful when you are starting to drill.