Drillin' Holes

[The Dougler]

I need to drill about a 1'' diameter hole in the fiberglass/gel coat that's in the glove box to install a usb socket for the head unit. Anything I need to know in order to not screw up the finish in the surrounding area? Will a key hole drill bit do the job for me? how do i make sure there's no chipping etc?

 

[Sid Schuster]

Re: Drillin' Holes

Just drill a pilot hole then use a hole saw bit and don't push too hard. Nice and easy and it should be OK. Go from outside(Gelcoat side). If by "Keyhole bit" you mean a flat "spade" bit I wouldn't recommend it, it might cause undesired chipping.

 

[The Dougler]

Re: Drillin' Holes

by key hole saw I meant this:

Which is apparently just called a hole saw.

 

[MRS]

Re: Drillin' Holes

That's what I use plus I do put masking tape down where I am going to drill first...... The hole saw I use also as a drill bit in the center of it to start the hole saw bit.

 

[superpop]

Re: Drillin' Holes

I think you want one with a drill bit or pilot bit in the center, and when you first start drilling, go in reverse for about 5 seconds to smoothly cut through the gel coat and then reverse and drill normally. Otherwise you will have a jagged edge with chip out where you drill.

 

[The Dougler]

Re: Drillin' Holes

Thanks for the tip. I have a hole saw set with the pilot drill so no worries there, but running in reverse for a few seconds seems like a great idea. Now hopefully it will drop below 100F outside so I can bear to be outside long enough to do the job.

 

[Mark42]

Re: Drillin' Holes

That's what I use plus I do put masking tape down where I am going to drill first...... The hole saw I use also as a drill bit in the center of it to start the hole saw bit.

Ditto. Masking tape has magic power when drilling holes in gel coat. Its absolutely amazing how a piece of sticky paper will prevent chips in gel coat, but it does.

I've heard of running in reverse to start, but have not done it.

 

[cr2k]

Re: Drillin' Holes

Reverse running to start works good, so does taking an exacto knife and running a scribe around the hole saw once the pilot hole is drilled. It kinda gives the gelcoat a fracture point and helps make a clean cut.

 

[Beefer]

Re: Drillin' Holes

Tape, and run in reverse, as said earlier. Same as if you're drilling through a laminate countertop.