Drilling Fiberglass

Post by **Markus** » Fri Jun 04, 2004 11:41 am

I'm mounting a planner mast this weekend and I need to install the mounting bracket to the front of the bow. I need to drill 4 holes into the fiberglass.

Can I use a normal wood bit?

Would I drill at high speed or low speed?

Should I put a peice of tape down first? would this help with spider cracks?

This will be my first time putting holes in my boat....a little nervous about screwing it up!

Post by **McQ** » Fri Jun 04, 2004 11:59 am

Markus, use tape (masking tape is great), high speed drill and don't worry, everything will be fine.

Have you given any thought to under mount support, there can be stress from a mast and the support will spread the load. Maybe a piece of 1/2 plywood?

Post by **Jamesh** » Fri Jun 04, 2004 12:07 pm

When bolting down the mount make sure you use nylock nuts so that they do not vibrate loose later. Do not forget to use stainless,don`t want rust stains.

Post by **franklauzon** » Fri Jun 04, 2004 12:09 pm

Mey Markus,

My absolutely non-professional, but baed on experience response would be to use Tape, The speed of the drill doesn't matter, and I find a dull bit to work better... it doesn't seem to pull itself through as quick...

Maybe that's just me though...

Post by **Markus** » Fri Jun 04, 2004 12:15 pm

McQ wrote:Have you given any thought to under mount support, there can be stress from a mast and the support will spread the load. Maybe a piece of 1/2 plywood?

I have a 1/4" plate of alluminum to go underneath. I also have 5/8" alluminum. Do you you think this would surfice? No rust, and should be strong enough??

So a wood bit is OK?

Thanks for all the help guys.

Post by **nighttroller** » Fri Jun 04, 2004 1:21 pm

I put mine through the floor board on the front deck of a Legend boat and I never had a problem. I just used big washers on the underside of the wood. I think either the 1/4 or 5/8" aluminum backing would be fine but if you want to be safe use the 5/8"! I recently bought a fiberglass boat and I am like you, the idea of drilling into her scares me a bit. Good luck!!

Post by **McQ** » Fri Jun 04, 2004 1:41 pm

Markus, the 1/4" aluminum plate will work fine. You would want something thicker if using plywood.

Use a high speed drill, preferrably a really sharp one and a little oversize. You want a fast clean hole, do not use a wood bit they wobble and you'll hurt the glass for sure.

If your deck is make like others I am familiar with the glass is laminated over marine plywood, be sure to seal the holes with a bit of silicone on the bolts. This step will slow down any water seepage and ultimate softening of the floor. If your deck pan is laminated over aluminum then don't worry.

Previous advice about using stainless fastenings and nylock nuts is a great recommendation and I'm sorry I missed that little clue in my first response.

Post by **Clipper** » Fri Jun 04, 2004 4:55 pm

Markus, check out this URL, it will take you to an article on drilling holes in fibergass boats.

http://www.sailnet.com/collections/arti ... suelar0169

Good luck.

Post by **Wall-I-Guy** » Sat Jun 05, 2004 6:27 am

Clipper wrote:Markus, check out this URL, it will take you to an article on drilling holes in fibergass boats.

http://www.sailnet.com/collections/arti ... suelar0169

Good luck.

Hey Clipper, welcome abaord

Yet another helpful member. that's what makes the board so great

Post by **big-o** » Sat Jun 05, 2004 8:40 pm

Clipper

welcome to the site....thanks for the tip!!!!

Marcus... how are you getting around the fiber glass support under the front deck plate

Make sure you don't tighten the bolts too much and crush that the fiber glass reinforcment

Fish-Hawk.Net

Drilling Fiberglass

Drilling Fiberglass

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