Prepping screws for reinsertion

[dragsterhund]

If I need to remove a screw from the deck to replace a piece of hardware, say, a cleat, bimini cover mounting bracket or cheek block, and I want to use the same screw, in the same hole on the deck, do I need to prep that hole before I reinsert the screw? A squirt of 4200? Some other sealant?

I seem to remember reading that removing a screw from fiberglass and replacing it in the same hole can only be done a few times before the fiberglass weakens too much. Should I fill the screw holes with epoxy and repilot/rescrew after it dries?

[model 10]

You must be talking about self taping or sheet metal screws. I doubt your cheek block is held on with these type fasteners? A bit of epoxy with some flox or something works great for old self taping screw holes.

[Cheechako]

most anything should be bolted rather than screwed. With at least large fender washers on the back side where possible. I never screw anything. Ifno other way, I drill and tap the fiberglass.
But......Clean the screw (I replace them) and add a dab of sealant for sure. Under the fitting and on the screw threads.

[cabo_sailor]

For myself, if the screw is cosmetic in that there is no stress, e.g. A cover plate or even a deck scupper grate, I just make sure the old screw is not stripped. For anything that might take a load. The original hole is filled with something like epoxy or Marine Tex and a clean hole drilled for the old fastener.

If it's a spot that can allow water to leak below or into the core, I would drill a larger hole, fill it with epoxy and let it cure. THEN I would drill the correct size hole for the screw or preferably bolt in the center of patch.
A little more effort but a hell of lot cheaper than repairing delaminates glass.


Sent from my iPhone using Cruisers Sailing Forum

[roverhi]

For through bolted fittings that pass through soft core like foam or balsa, best to rout out the core around the fastener, fill with thickened epoxy and then redrill the hole. I use a Dremel 199 bit to do the routing out, use a syringe to pump in straight epoxy resin to thoroughly wet out area then suck out as much of the resin as I can with the syringe, add in the West 404 filler and squirt it back into the hole. Redrill the hole and counter sink so there is a sealant pool at the top of the puka. If I'm careful, the fitting hides the fix. Use good sticky duct tape to seal the bottom of the puka so the resin doesn't run all over. Masking tape won't hold and epoxy is a bitch to clean up off a teak and holly sole. If there is a liner so you can't get at the bottom of the puka to seal it, have been told that construction foam sealant, the kind that actually gets hard, squirted into the hole before you rout out the core works to seal the bottom.

If you are talking self tapping or sheet metal screws, they will eventually hog out the hole and no longer hold if unscrewed and rescrewed a few times.. Should only be used for non structural hardware as the fasteners will pull out if subjected to cyclic shear loads. Won't hold at all if used in matt/chopper gun layups like cabin liners sometimes are made of. If you do have a fasteners that is screwed into the layup and strips out, fill the hole with epoxy resin, maybe with a bit of 404 added, and redrill the hole.

[chriscraft]

Would also recommend that if you are either plugging and re drilling or choose to use the same hole with 4200 to keep it dry that you ensure the hole has a bit of a countersink before caulking and screwing. Regardless of the anticipated level of stress on the screw, you'll want to minimize the chances of any stress cracking the gel or the glass at the surface of the hole. Countersinks are a great insurance plan for that.

[Lepke]

If the screw goes into your core or wood, do as roverhi described. When you redrill the hole you may need a slightly larger hole because epoxy doesn't give. I also squirt in some additional epoxy when I drive the screw. This way you never compromise your core.

[cwyckham]

If the hole goes anywhere near the core, you'll want to read this great article by MaineSail on sealing deck penetrations.