Which glue for repairing dovetailed balusters?
I have a loose balusters on the main staircase of an old home. The bottoms are dovetailed into the stair treads and doweled into the upper floor landing. I need to fix the banister now because it is loose and I have small children, but someday in the future I hope to really renovate the staircase so I don’t want to use epoxy or regular wood glue that would make it impossible to take the stairs apart in the future. I know that hide glue can be reversed with heat/humidity, and I read a posting suggesting cyanoacrylate (removable with acetone).
Could anyone comment on either of these two options, or suggest another approach? I don’t think the dovetails would be strong enough to screw through, even with pre-drilling, so I think I’ll need a glue of some kind.
What made these banisters tight when they were made 100 years ago? Were they glued or did the wood simply have more moisture (thus making the dovetails bigger and tighter)? Or, could the problem be simply that the pieces of trim that hold the dovetails into the treads have loosened over time?
I am an amateur, so any input from the pros (or more experienced amateurs) would be appreciated?
Thanks!
Replies
Generally cyanoacrylate (Krazy Glue) is a bad choice because it's quite stiff and brittle. A good wood glue needs to have some "give".
They were not likely to have been glued when new and probably shouldn't be glued now. They just fit back then and, if they didn't, would have had a shim added to make them tight.
If the balusters are loose now it could be because the wood has been compressed by being levered against the sockets over the years. You can take off the trim piece, the end nosing, and add a thin shim, not driving it too hard, and then replace the nosing.
Looseness in the rail is more likely to be due to looseness in the newels and joints in the rail. Without being able to see the installation, I have no useful advice to offer about that.
Ron
It would be interesting to know if they were glued originally. If you see what looks like brittle amber colored glue, it may well have been hide glue. If it is hide glue, new hot hide glue will re-soften the old glue. Also, both white glue and original Titebond are reversible with heat and water, but hide glue is considered the ultimate in reversible glue. I've never had too much success with hot hide glue; there are too many variables to get right for my skill and patience level.
Below is a link to a white glue formulated for instrument makers. They say it dries hard and is reversible. Instrument makers on my other forums say it's great stuff.
http://www.lmii.com/carttwo/thirdproducts.asp?CategoryName=Adhesives&NameProdHeader=Instrument+makers+glue
Dovetailed ballusters were not glued originally. The old timers knew you may have to repair or replace sometime in the future. If you remove the tread return, you should see the balluster has a single nail in it. Glue isn't likely to hold due to the tread movement. Take out the nail and either put a larger one in or use a trim head screw.
You could add support if the landing is close enough
Hide glue was generally used for furniture. I second the recommendation for shims - but use hardwood shims.
If the handrail doesn't have enough support or lacks sturdy anchorage into newel posts, and if it bypasses the landing (within a few inches) you can make a support using the following technique:
Buy a steel lag screw of 1/4" diameter and some steel pipe that the lag can pass through. Find a spot under the rail where the lag can be driven into the landing edge - preferably into solid wood. Drill a pilot hole and use a ratchet wrench to drive the lag screw into the landing until the head comes up on the handrail. Now, back the lag out slightly, enough to cut the head of with a reciprocating saw with a metal blade. Using vice grips, turn the lag back in until it lies fully under the handrail. Now, slip the steel tubing (primed for paint) over the lag - cut it to length so that it will just cover the cut-off end of the lag screw. Now, drill and countersink holes straight through the lag shank - carefully - into the bottom of the rail and screw the lag into the handrail.
Paint the support and you're done. You might be surprised how effective this is in adding support to a railing.
Jeff