Replacing screws

[Kaa]

A quick question.

If I have to take out a bunch of screws from a piece of plywood, what should I do to the holes before putting the screws back in? Keeping in mind that I might have to repeat this, so I don't want to fix the screws in there for eternity. Is the proper procedure different for plywood and for wood?

Kaa

[Thorne]

Is this "piece of plywood" on a boat? Will it be under water or out in the weather? Are they going into anything other than the ply, like a frame or base?

GIGO, my friend....

[Kaa]

Yes, on a boat :-) Above the waterline. The screws (predominantly stainless) sometimes go into solid wood and sometimes into another piece of ply.

Kaa

[The Bigfella]

I drill all screwholes into ply out to about a 1/2" diameter and fill with a reasonably thin filled epoxy. Typically I have to top these off due to the soak in effect. When dry, sand flush, drill your pilot hole and Bob's yer Uncle.

ask me why I go to all this trouble - and the answer is that it is much easier than the replacement process.

[Thorne]

As above, why make them removable at all? Water wicking into the plys via fastener holes may be the main reason that some boats rot while others don't -- one reason that Oughtred's glued lap construction without many fasteners or holes of any kind is gaining converts.

I'd either go the epoxy route as described above (the recommended method) or use red lead as a combo screw lubricant/anti-fungal material.

[Kaa]

As above, why make them removable at all? Water wicking into the plys via fastener holes may be the main reason that some boats rot while others don't -- one reason that Oughtred's glued lap construction without many fasteners or holes of any kind is gaining converts.

I like the ability to assemble/disassemble stuff without doing major damage to it. It makes proper maintenance much easier, which, in turn, means you're less likely to find bad surprises in a few years' time.

Anyway, I don't have in mind hull fasteners or anything majorly structural. The question is mostly about smallish things on or above the deck -- for example, cleats. If I take off a small cleat and then want to put it back, do I really need to drill a half-inch hole, fill it with epoxy, and then screw my fasteners into that epoxy? Sounds like overkill to me.


I'd either go the epoxy route as described above (the recommended method) or use red lead as a combo screw lubricant/anti-fungal material.

I don't need a lubricant as much I need a hole filler. Once you've taken a screw out, it won't hold as well if you just screw it back in.

Kaa

[The Bigfella]

If I take off a small cleat and then want to put it back, do I really need to drill a half-inch hole, fill it with epoxy, and then screw my fasteners into that epoxy? Sounds like overkill to me.


Overkill? Hardly. Also definitely better than the kill caused by wet ply. You cannot stop moisture getting in to ply any other way.