Glue Choices for Chairs and Stools
Furnituremakers discuss which glues they like, and why. April 30, 2006
Question
I have a big batch of stools to do, and after gluing some chairs lately with polyurethane glue, I think I need to switch. The poly glue was foaming and even if I cleaned it with toluene it was swelling away again, making it a real nightmare to clean. Does anyone know of a tough glue which is either easy to clean or doesn't make a glue stain when varnished? I was thinking cascamite, but is there something better?
Forum Responses
(Furniture Making Forum)
From contributor A:
Hot hide glue.
From contributor B:
I have been making benches and chairs for about 8 years now and only use Franklin's Tite Bond. While wet, it is easily cleaned with a damp paper towel. Once dried, if there is a small bead, it is easily chipped off with a knife. It sounds like you get quite a bit of squeeze out. I suggest tightening up the tenon in the mortise and cut down on the amount of glue. On the stretchers, if the design allows, pin the mortise-tenon joint with a 1/4 inch dowel if you don't tighten the tolerance.
From contributor C:
If you just relax and let the urethane foam out and harden, the clean up is real easy. Once hardened it can easily be scraped with the Red Devil or similar scrapers, a chisel, or easily sanded off. It will not clog sandpaper once cured. The trick is to leave it alone until it is solid. You can use far less urethane than yellow types, helping to offset the cost and reducing the foaming. Do remember to mist one side of the joint before joining if the wood is under 10% MC. The bonds are as good, and clean-up easier than with other glues.
From the original questioner:
I've tried all the ways - clean fresh, semi dry, dry and none work. I have to clean in corners where I have the grain running in different directions, and scrapers just tear out the grain. Cutting with a chisel and sanding is not working either, because it's too slow. I'm not working on antique furniture or guitars. I have some Titebond, and I’m going to try it, but knowing a bit about it, I’m worried about the creeping with the chairs. I do tight tenons, but I don't dowel. I have to follow the plan.
From contributor B:
If you are gluing up blanks for seats, creep is not much of a problem, and the only time I have had a tenon pull out of a mortise on a stretcher is when it got frozen before it fully cured.
From contributor D:
If you are looking for glue that has the performance of the Polyurethane without the foaming, there are options. You can use hot melt polyurethane. They have very short open times so you need to be careful there. There is also 2 part epoxy glue. For simple chairs and stuff we like the moulding glue from Titebond because it is thick and won't run. You will get similar performance from the Elmer's Probond glue which is also dripless. It is a better color that the Titebond as well.
From contributor E:
PL Premium Polyurethane Construction Adhesive
From contributor F:
There's no silver bullet in glues. I think the rational approach is to ask yourself what the lifespan of the chair you are building is going to be. If you think your chair will be thrown away after ten years then PVA, Polyurethane, and Epoxy are probably good choices. On the other hand, if you wish your chair to be an heirloom, easily repaired (ie cost effectively repaired) then hide glue is the only logical choice. If you check the numbers, you'll see that the bond strength for hide glue is marginally higher than that of PVA. So what it really comes down to is do you want your chairs to end up in the Smithsonian collection or in the land fill collection?
From contributor G:
We use a product called Waxlit for glue ups such as chairs. You do a dry assembly then coat the surfaces around the joint with the Waxlit. Then, when you glue up, the squeeze out just pops off the areas where you don't want it. You wash off the Waxlit with non oily thinners. We get it at Lee Valley. I like Titebond glue. I know what you mean about the foaming out - I've been there!
From contributor H:
I have been using "Old Brown Glue" for about six months. Warm it up to about 90 degrees F and it flows well. Easy clean up, it stains and varnishes well, and it is repairable. I'll not go back to the hot glue so long as I can get this stuff. It is a bit pricy, and it has a 1 year shelf life. I've been through two 16 oz containers in the 6 months and not a single problem.
From contributor I:
The glue you that you use won't get you in the Smithsonian. All glue eventually will fail, especially if you're relying completely on it to hold your work together. Glue is essential but a real chair will stand when the glue lets go..
From contributor J:
The point about the Smithsonian is that most glues are not reversible like hide glue. A chair that is made using epoxy for the adhesive for instance will be impossible to disassemble for repair if necessary.
From contributor F:
The ability to repair the chair is important. Last week a prospect asked if I could give a price on repairing a factory Windsor chair along with her dining room table set. Before giving her a price I explained that it would take one to two hours to turn a new leg and new stretcher, another hour to extract the stump of the broken leg, another hour to sufficiently clean the mortise out, etc. She quickly got the point that it simply wasn't worth it to repair this chair. The chair was never meant to be repaired. Consequently, it was a great opportunity to highlight the differences between factory and custom.
From the original questioner:
Thanks for your replies. My chairs are cheap, straight legged basic things. They need to last the next 5 to 10 years, and that's it! Hide glue could be interesting, but too labor intensive - heating up the tenons and mortises, plus the wood tends to swell with the moisture if you want to use full strength hide glue. I didn't know about the Waxlit product, but I’ve been thinking of using simple shellac or wax, depending on what the future finish will be. Epoxies are mostly thermoplastic waxes used as glues. Except for a few which are thermohardening, the first ones release above 80 to 120 Celsius, while the second ones are curing and getting harder with heat.
