Join Date: Nov 2009
Thanked 58 Times in 54 Posts
Rep Power: 5
Re: Do I have to predrill before running screws into fiberglass
Originally Posted by jimgo
Lining up the holes isn't THAT hard (and I'm lazy):
Drill the holes in the wood.
Put the wood over the fiberglass and tape it in place.
Put a bit in the drill that is the same size as the holes in the wood, so you're using the hole in the wood as a guide.
Slip the bit into the hole and just kiss the surface of the fiberglass.
Repeat for the other holes.
Remove the wood.
Put the proper sized bit in the drill.
Drill the pilot holes at the point where the drill kissed the fiberglass.
Chamfer the edges of the pilot holes.
Put the wood back over the newly drilled and chamfered holes, and add the screws.
Oops, sorry I didn't answer your original question. Yes, this procedure seems fine. Just chamfer the holes, and bed with butyl.
Um... I'm a real stickler about water intrusion and core rot. If this area isn't solid glass, I'd over-drill every one of these holes, fill them with epoxy to seal the wood core, then re-drill them to the proper size for the screws, and bed them with butyl tape.
If the area is solid fiberglass, then just carry on with your procedure.
S/V Old Shoes
1973 Pearson 30 #255