Reply To: Abandoning a glue-up

I am not sure that’s entirely correct. If the PVA glue has not yet cured, you should be able to remove it with a wet rag, a chisel, or some sandpaper, depending upon how much it has started to harden. To get the best glue joint, you should sand it down to fresh wood, but I don’t believe that it is absolutely necessary if sanding it down completely is impractical. Just a bit of sandpaper in the mortise or tenon (depending upon which you are keeping) should be all you need. I agree that once completely cured, removing enough of the PVA from the joint without damaging the underlying wood will be a real pain, and may not be practical in some cases.

Also, if you are making a new side anyway, you could always cut the new mortise to match the dimensions of the freshly sanded tenon.

I’m also not sure it’s correct to say that cured hide glue can be “reactivated”. Cured hide glue can be reversed with heat and moisture, but once loosened it should be removed if possible. It is more forgiving in that hide glue will bond to a thin layer of hide glue on an existing joint, but even so it will work better on bare wood.

Where dried PVA can pose a problem is with finishes. Even a thin layer can prevent some finishes from penetrating, and sanding it all away can be difficult. Hide glue is more forgiving in that respect. Also, hide glue is more easily reversed after it cures.

Like everything, whether you use PVA, hot hide glue, or liquid hide glue, each type of glue has its benefits and tradeoffs.