Chairs and liquid hide glue vs white Glue All

[Dave Lehnert]

I have some old chairs I am restoring. It was suggested I use hide glue.

Some questions

- Hide glue has a longer open time. How much longer vs Elmer's white Glue All?

- Parts with hide glue can be taken apart if needed. That is my concern using it with kitchen chairs. How strong is Hide Glue?

What glue would you recommend for chair repair?

NOTE- I am referring to the liquid hide glue.

[Brian Kent]

In the Fine Woodworking test, hide glue was strong, but not quite as strong as PVA or slow-set epoxy. Liquid hide glue was very slightly stronger than regular hide glue. The exception was on oak with a tight joint, liquid hide glue was second only to slow-set epoxy.

[lowell holmes]

I have had to repair dining room chairs for one of my daughters. The chairs are poor in design and have joints that are not strong. They fail when someone leans back in the chair.
You can take apart an old white glue joint with warm white vinagar water. The surface has to be spotless clean prior to using the white glue. This involves a lot of scraping.

Some of the joints had been repaired using Gorilla glue. They were worse than the white glue.

The original joints were glued with hide glue. I used real hide glue. You can heat the glue in a coke can placed in a pan of boiling water. You don't need a glue pot.

On hide glue joints, minimul cleaning is required. When you place new hot hide glue in the joint, the old glue dissolves into the new glue and the joint is strong.
Books on repairing antique's speak to this issue.

I suggest you repair one joint to develop the procedure. After you know how the job will go, jump in with both feet.

I think if you use white glue, you will regret it if the old glue is hide glue. Like I said, do one chair and see how it goes.

[Dave Lehnert]

How do I know if hide glue was used?

One problem I have is someone in the past had done repairs using some kind of glue. Kinda looks like clear silicon but not.

[Mike Henderson]

The problem with repairing old chairs is that usually the joint is loose, meaning that the wood has shrunk or has been worn from movement - people keep using them after they start wobbling. What I like to do is take the chair apart and tighten the joints. If they used dowels, I'll often re-drill the holes to the next larger size dowel, then re-glue with larger dowels. If mortise and tenon, and the tenon is really loose, I'll glue veneer to the sides of the tenon before re-gluing. In all cases, I try my best to remove all the old glue.

When I re-glue, I usually use a slow epoxy because I feel it's the strongest and it does gap filling.

In a case like your's, where the joint has been repaired with some unknown glue, I'd strongly recommend taking everything apart and cleaning the wood in the joint before re-gluing.

Mike

[Prashun Patel]

Personally, I think it depends on what you're repairing. If you're repairing things that may break in the center - not at the joint - like spindles or stretchers, then it might be worth it to use hide glue. These joints also don't require the strength that the leg/seat or arm/leg joints require. For those joints, failure is likely to be AT the joint, which means an epoxy might be more appropriate.

[phil harold]

As Mike says some joints are damaged from movement, a foxtail joint can be incorporated into the repair.

my personal opinion would be not to use epoxy on chair joints,
wooden chairs are supposed to move and be a little loose this make the chair comfortable
also if the repair fails again epoxy joint wood be hard to repair
while a pva or hide glue can be soften with heat and disassembled

[Howard Acheson]

For chair repair and new chairs I only use slow set, two part epoxy. In the shop I ran we built a line of semi-custom furniture for a well known interior decorator. The interior decorator and the shop jointly funded a series of tests by a stress and strength testing company. The only adhesive that held up was the slow set, two part epoxy. Hide glue was one of the first to fail as it is a hard and brittle adhesive. Therefore as joints work--as they will with chairs) the adhesive cracked. Most of the PVA joints held up but some failed. The shop, interior decorator and our insurance companies did not want to take the chance. Epoxy is slightly flexible and will not fail under repeated racking. For repairs is was far superior to hide glue. The only time we would use hide glue was if we were repairing a true antique.

[lowell holmes]

I agree. I always clean the joint and get the crud out. It's just that with the old glue being hide glue, you don't have to remove all traces of the glue. The warm glue you put back in the joint re-activates the residue that was left.

Dave, if the old glue is brownish color and is soluble in hot water, it is probably hide glue. I would work one joint and see whats there before committing to the whole repair.

The issue I have with epoxy and with carpenters glue is that the repair is not reversable.

[Mike Henderson]

The issue I have with epoxy and with carpenters glue is that the repair is not reversable.
I don't worry about reversibility because if the chair comes back to me with a loose joint, the glue has failed (or the wood has broken). On chairs, the joint that fails is where the seat goes into the back - and I've never seen a chair where one side failed and the other didn't. If I did ever have such a situation, I'll simply cut the other side with a thin saw (like a Japanese saw) and then put a loose tenon in that side.

Chairs that come to me for repairs are not valuable antiques. They may have some sentimental value to the owner but to anyone else they aren't worth much. If a chair is an authentic, valuable antique, I recommend they take it to a specialist conservator for repairs.

Modern glues, such as slow setting epoxy, are so much better than animal glues.

Mike