Using epoxy in old screw holes?

[mrybas]

I will be reinstalling several items that were screwed or lagged into the deck and cabin-top (hatches, ports, deck prisms). I would like to have maximum screw holding when reinstalling the new screw and would like to know the best method to achieve this? The other day I reinstalled a deck prism that I over drilled the old screw holes (next drill bit larger than the existing screw hole), filled with cabosil thickened epoxy, then drilled a pilot hole once the epoxy cured. 5/6 of the screw achieved a real nice bite, but one stripped out before the frame was properly bedded down to the deck. Is this the best method, or is there a better way?

[Maine Sail]

Best bite is through bolting.. The best way to ensure a good thread interface is to pot the hole with the screw in it. Treat the screw with cooking spray or wax first though so it will come back out after cure...

[mrybas]

I like the wax/cooking spray suggestion. Would thickening the epoxy with colloidal silica or milled fibers make a stronger hold? Someone on another forum suggested enlarging the old screw hole, fill with epoxy, then tap it after cured, then use a machine screw. This sounds like a good method, no?

[oomfh]

West System has an epoxy product called G/flex - flex meaning elastic - so you don't have to coat screws and insert them while the epoxy is curing. I filled some old screw holes in my teak handrails, let cure 24 hours, drilled pilot holes and achieved great holding strength.

http://www.epoxyworks.com/26/pdf/Fas..._toughness.pdf

Good luck!