Drilling through Fiberglass - 101

[Jedi Bob]

I am in the process of a new outfitand I need to make a small hole into finished fiberglass. I am very nervous as I do not want to ruin or crack the finish.

How should I do this? I was thinking of placing a few layers of masking tape on the finished side of the armor and using a tiny drill bit on the dremel make the hole. Then using gradual sizes of drill bits, keepon working on the hole until I get the right size.

Hopefully, the masking tape will preotect the finish and it won'tcrack.

Any thoughts orideas would be MOST welcomed.

 

[fettpride]

Heya ! Long time no see

Your caution is certainly not out of line. It seems every time I drill into gelcoated fiberglass, I at least chip it up a little bit (the gel coat).

I'm not sure that there are any miracle tricks to preventing this. What I DO know, is you should be very careful with doing the different bit sizes up from a small pilot hole. The reason for this is the pilot hole may give the next sze bit a place to dig in, but it also promotes chipping the gelcoat from the previous sized hole. It's actually better in my own experience to start with the bit size for the finished hole that you need, make sure it's really sharp ... then go slow and easy. When you get past the finish (gelcoat) your gold.

If you're really sketchy about this, I think what you said about the dremel is your best bet. Use it to start the hole. But don't size up your bits form there. Use the dremel to continue working the hole to the size you need.

Now maybe I didn't understand completely. You said "finished" fiberglass. Are we talking painted???? If that's the case, the the tape is most definitely in order. But in my experience it won't stop the cracking. It's only good if you slip and run a blade over an area you didn't want. A couple of layers of tape is good for an interference layer. But not for chipping and cracking. If it's going to chip, it just will. You never can tell what's in the gelcoat. There could be an air bubble right there .. where you are wanting to drill Sorry, not trying to make it worse for ya

Wish i could be more help. If someone else has a special trick, I'm all ears as well !!

Good luck bro,

FP

 

[FettFanatic]

I have used a carbide cutting attachment on my dremel to drill holes through fiberglass. This is the one I use.

http://www.dremel.com/en-us/attachm...accessory-detail.htm?H=188537&G=66240&I=66305

You can use the tip to plunge through the fiberglass, but go slowly. With the cutting surfaces being so close together it gives the bit less chance to catch the gelcoat and rip a piece out of it. Well that is at least how I think it works. You can then use the side of the cutter to enlarge the hole a little at a time. Like I said I have used it in the past with good results. Good luck on your project.

 

[SinisterFett]

In my experience of drilling through gelcoated fibreglass is to use a couple of layers of masking tape to stop the bit from scooting across your nice smooth finish and to use the size of bit that you want the hole to be. but set your drill or dremmel on a slowwww setting, that way you'll minimise the chances of your gelcoat chipping. However as Fettpride said if it's going to chip it will, it's just one of those things.

 

[CombatBaby]

you got it, just go easy with it and mask off the region you are cutting.

i do this everyday, and it helps to be easy with it and not be forceful.

 

[Jedi Bob]

Is there a specific Dremel bit that is recommended???:confused