Cutting Big Holes In Fibreglass

[davidimurray]

Anyone got any advice on how to drill the big holes in the rear wings for lights. I've had a few suggestions from chain drill and dremel to holesaw running backwards.

Has anyone who has done it got any advice?

Cheers

Dave

[fabbyglass]

Cover the area where you want the holes with masking tape, mark out the holes and chain drill them but use a blunt drill as a sharp drill pulls thru too quick and will chip the gel coat. When you have your ring of holes break the centre out then clean up to your marked edge with a file or dremel...beware the dreaded 'glass dust though;)

Air whizzies are better as spin a lot faster than those dremel things and the tooling you can get for them is bigger to so takes a bit more abuse.


wear a dust mask and goggley things as glass bits in yer eye don't half hurt..:)

[wylliezx9r]

I used brand new multi use hole cutters running forwards from screwfix. Didnt chip the gel coat at all and was much easier/quicker than chain drilling. If using this method don't bother with masking tape as it just gets ripped off as soon ad you start drilling. Obviously drill a small pilot hole to start off before you go in with the larger bit on the arbor.
Cheers Dan

[AshG]

i used a hole saw for mine worked a treat. i put masking tape on the wing then marked the centre point then drilled it

http://i707.photobucket.com/albums/ww75/ashgardiner/Running%20Gear/P1030031.jpg

http://i707.photobucket.com/albums/ww75/ashgardiner/Running%20Gear/P1030032.jpg

[spud69]

As said Dave these work a treat:

http://www.screwfix.com/prods/47149/Drill-Bits/Holesaws/Cobalt-Holesaws/Bosch-Cobalt-Holesaw-70mm

If you do then drill the pilot hole separately then drill through with the hole saw with just very light pressure so that it doesn't dig in and rip the gel. Practice on a bit of scrap first.

All the Best.....AndyH

[Bonzo]

Hi Dave

As others have said, I much prefer to use decent hole cutters ( As per Spuds link )

On soft stuff like GRP I normally use my cordless drill .... I tend to go a bit mental with the electric drill :eek: :o

If I am worried about cocking things up, i'll measure a gazillion times, mask the area off, drill the hole 1 size smaller than needed & fettle to size with my die grinder or round/half round coarse file .... Well, you lot know me, like to do it the hard way if at all possible :D

[davidimurray]

Thanks for all the tips and advice guys - planning a day in the garage tomo so hoping to get the reat wings fitted and make a start on the lights. Will post some pics when they are done.

[davidimurray]

Holesaw worked a treat :D

http://img262.imageshack.us/img262/6393/dsc02745a.jpg

http://img3.imageshack.us/img3/8987/dsc02744cj.jpg