I believe here the answer is not to fill the void (loose joint) with glue,
but to close up the gap (tighten the joint)
Lets say the loose joint is the handrail to the newel post. No amount of
filling will tighten up the joint or truly fix it for the log run. Here, to
tighten up (close) the joint you need to draw the to pieces together
(handrail and newel post) I would do this with screws. If a box newel pot
remove one of the sides so you can drill a pilot hole in the newel post (use
a bit the same diameter as the screw shank) then drill a smaller pilot into
the handrail. now drive a screw to pull the two pieces together. If the
newel is solid you will have to drill through the post (same as above) and
plug the hole after the screw is driven.

Good Luck

Jeff

"Nehmo" wrote in message
...
I have an ornate wood interior staircase that is several decades old.
Many of the railing joints are loose to one degree or another, and I'm
going to make them more solid. It would be chore to disassemble &
reassemble the entire railing assembly to repair, so I'm trying to come
up with another method.
I've never done this, but is it a reasonable idea to drill holes, say
3/16" diameter, to every joint (in places that aren't very visible) ,
and then use a syringe to pump some polyurethane glue into the joints?
In some places I could also drill holes and insert trim screws.

Recommendations welcome.

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