Loose stair spindles

How dry is the house? Mahogany can move quite a bit and with the advent of air conditioning, this can create this problem. What you have is the tread and the balustrade shrinking, creating your gap. Once you get some humidity in the house, these will tighten up and if the gap is filled, the wood will split.

My recommendation would be to leave them alone. If you want to make them tight, glue only one face and put a wedge in the other side to hold it until dry, then take the wedge out. This will keep them from rattling and still allow for movement.

-- Love woodworking and fixing most anything

We use silicone caulk. It allows for some expansion and contraction. On 1/8” gap you may need to inject with a syringe. Don’t fill the area. Just enough so that the spindle will not move when the caulk is set. This doesn’t add any strength, just keeps them from making noise.

Have you thought about the entire removals of the spindles instead? Perhaps you can find a way on extending them once they’ve been taken out and then put them back in once you’re able to find a good solution for the problem.

-- Marcio Wilges @ http://www.platinumremovals.com.au/

Thanks for all the feedback. I don’t have Ac as I live in Mass, my house is well shaded, I have 10’ ceilings and a whole house fan in the attic.

However I didn’t consider that humidity could have caused the gap, which is more than likely.

Perhaps silicone would work if I could get it in with a syringe as the gaps as 1/16”. If this doesn’t work then taking the spindles off could be the next step.

I already use silicone and it was a good choice

-- Pascale, Cannes, http://www.lesoccasionsauto.com