Will joint compound stick to plywood?

I was doing some electrical work at my in-laws this weekend and had to relocate an electrical box. Unfortunately, they have plaster and lath wall construction that quickly crumbled away as I was cutting the hole (it had multiple cracks before I even started).
To get things fixed up as quickly as I could, I mounted the electrical box and repaired the hole with the only supplies I had available at the time, an old piece of 1/2" plywood. The switch box has a nice sturdy mounting and it holds the wall together nicely.
Of course, the piece of plywood and the crumbled plaster edges don't look all that great, so I'd like to patch it up a little to make it blend a little better. The rest of the wall is in pretty rough shape already, and we're planning on remodeling that room in a few years anyway. It doesn't have to be top quality, but I don't want the patch to crumble away in a few weeks either...
So, I'm curious if I can apply joint compound directly over the plywood patch? I would use fiberglass mesh tape to control cracking, but will the compound stick to the plywood? The plywood is very dry and has a rough texture.
The overall patch is about 6" wide x 9" high.
Thanks,
Anthony
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HerHusband wrote: ...

It will do fine. You could always staple a small chunk of screen or similar mesh to provide a little more "teeth" but more than likely for the purpose of a "temporary" patch no larger than that you could get by with just a skim coat then a finish coat (or two).
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I know it's practically impossible to remove joint compound I've dropped on a plywood subfloor! :) So I figured it would work fine. I just wanted to see what experience others have had.
In any case, I just want to pretty it up a little. The whole house could use a complete gut and rebuild, but we can only do a little at a time.
Thanks for the feedback!
Anthony
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HerHusband wrote:

Actually, if the plywood patch is behind the plaster so you have the full thickness to build up, you'll probably get better results if you have some wallboard around in filling the bulk of the hole with it and then finish it like taping a joint. A full thickness a plaster wall w/ mud is likely going to crack. If the ply is at or very near the surface, as I was originally thinking, no sweat.
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Yep, the plywood patch is screwed over the existing lath, leaving the surface of the ply less than an 1/8" lower than the surrounding plaster.
Normally I would patch in with sheetrock, but when you're in a bind, you use whatever is available... :)
Sounds like the joint compound should work well. Thanks!
Anthony
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HerHusband wrote:

Hell yes..... believe me...joint compund will stick to anything that gets in its way... ~:>
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wrote:

Yes
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