Robert11 wrote:
....
Have a real old wooden bed frame that is in pieces, that I would like to put
back together.

It was originally held together by very large Biscuits, and a few Dowells,
it appears.

Re the biscuits:

a. Should I use an epoxy glue, or perhaps that Gorilla Glue which I think
they call an acrylic adhesive ?
Which would be better ? Why ? (anything even better these days ?)

b. Some of the biuscuits have old, very hard, dried glue on them.

Would either the epoxy or Gorilla glue work (well) if I don't go to the
trouble of sanding them clean ? Or, must I really get rid of the old stuff
before either would grab ?
(looks like a lot of work to try and sand them clean)

Some advice already --

How old is "real old"?

If biscuits are original that indicates more than likely 20s-vintage at
the earliest and machine, not hand produced.

The glue to use depends in part on what is there but the the general
advice of cleanup is sound.

Assuming the joints are original and not something already hacked on, if
you can take a hot, wet cloth and soften the glue, that would indicate a
hide glue which is certainly one possibility. In that case, going that
route as a repair would make sense.

Otherwise, if it is nonsoluble in water/heat, cleanup and dry fit as
well as possible, particularly to ensure dirt and years' of crud aren't
in the way. If the biscuits are larger than a current new one,
depending on what they actually are, you may be able to fabricate
replacements relatively simply from thin ply stock. Otherwise, cleaning
them before reuse is about the only reliable technique.

After that, if not using hide glue, I'd recommend any of the current PVA
wood glues--on a clean, well-fitted joint they're as strong as the wood
in well over 50% of joint tests so there's no need for anything stronger
than that.

I recommend against epoxies or polyurethanes (gorilla, et al.),
resorcinol, etc., as simply unneeded for the job and making additional
repair/restoration down the way if required nearly impossible, not just
difficult.

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