Hey all-
I’m doing a job in the next few weeks that involves gluing up a curved handrail. The homeowner ordered it himself. It’s pre-shaped and comes in strips. It’s NOT a spiral stair. It’s a framed up situation that turns 180 degrees over 9 treads. The outside radius is 4′. The handrail may end up being slightly less than that. Looking for some advice from those of you who have done it. My questions are:
A. The strips are thicker than I expected – in the 1/4 to 5/16 range. I’m expecting this could make for some serious springback.Thoughts on how much springback to account for?
B. Glue: In this pre-shaped situation using yellow glue sounds to me like a sanding nightmare. I was thinking polyurethane glue because of its easy sanding and longer open time.
C. Clamping: Rubber band clamp and clamped to curved jig? I’ll be jigging it up on-site with some kind of brackets screwed to the rough treads. can a rubber band type clamp hold enough pressure to keep the strips tight? I keep thinking of the rubber band clamp because it would hold the pieces in line with each other – as in across the top – between strips.
Thanks for your help.
Edited 1/16/2003 11:47:18 PM ET by Capperjohn
Edited 1/16/2003 11:50:12 PM ET by Capperjohn
Replies
Capperjohn
You are wondering about the springback, what is the radius? If its tight then maybe the 1/4" to 5/16" rips will be cause for concern.
When we glue up something of that nature we use yellow glue at times but it seems that we have better luck when we use West System epoxy, you can get different set up times so that helps with open time.
Your idea of jigs screwed to the treads is a good idea but I would not use rubber band type clamping. I dont think that you will get the tight clamping that you need. The good thing about the West Slystem epoxy is that it does act as a bit of a filler in the event that you dont get the joints tight enough, but I wouldnt settle for joints that arnt tight. You will need clamps galore, and them some more clamps.
It seems that you have a good idea, try a dry run first to see how it will go and maybe you can find some potential problems before they happen.
Maybe someone else will chime in here, if your lucky Stan will offer some advise, he is the king of this sort of thing.
Doug
Here's how we do it.
I am assuming that you have Coffman or some other manufacturer's bender rail.
Get your brackets set and braced, screwed down etc.
We use Liquid hide glue. I think it's made by Borden and comes in 1 qt bottles. It is easy to work with and has a very slow set time. I'm talking relatively slow here.
I agree that you will need plenty of clamps. I have boxes filled with 5" long plywood blocks with a hole drilled near each end and 6" carriage bolts to tighten down in between my bar clamps.
Springback is not a concern unless the glue is letting go and allowing the pieces to move. Once cured these rails are amazingly stiff. Don't be cheap with the glue and be prepared for some sanding and scraping.
-Doug