Gluing cross-braces of a Windsor chair back into the legs

[NY]

I have a wooden chair with four legs that fit into the seat, with front and back legs on each side held from splaying out by a fore-and-aft cross-brace; those two braces are themselves joined by a side-to-side brace. On one side, the braces have come loose from the holes in the legs, making the chair rickety. I tried gluing them with PVA glue but the glue joint broke almost immediately (after letting it set for several hours).

I don't want to have to unglue and re-glue any of the other joints (in case I make things worse). What is the best glue to use for sticking a joint where one wooden piece fits into a hole in the side of another? I can extract the cross-brace by about 10 mm, but there isn't enough play to remove the brace totally to line the hole with glue, so I have to rely on straining the joints to expose as much of the ends of the brace, smearing glue around the exposed part of the brace (at both ends) and then pushing it back together.

[harry]

You won't get a secure joint unless you remove all traces of the original glue. Even if it means completely dismantling the chair. You need some means of clamping the parts together until the glue sets. If the joints have a lot of play, you need a gap filling glue (not PVA) eg resin

[harry]

[newshound]

GIYF

This one is OK

Drill access holes as required with a small drill (less than 2 mm). A dremel type drill is useful for this.

[Rednadnerb]

Araldite is what I have used in the past. It didn't last, I've found that once chairs start to get rickety there is no saving them with glue, even screws do not give it much more life. I haven't tried completely dismantling one and regluing but I suspect that that is what you need to do.

[Bob Eager]

I did this with four dining room chairs about ten years ago. I used Cascamite.

They have been rock solid ever since.

[John Rumm]

The only glue that will cope with joints that are not snug fitting is epoxy. PVA has not gap filling capacity.

Disassembly, clean-up and re-gluing is probably the best approach.

For really good pull out resistance on a mortice and tenon joint, you would need a wedged or "foxed" tenon. With chair leg joints you normally have blind mortices, and so need hidden wedges.

Kind of like a round version of :

(typically the mortice in the leg is widened toward its base, and then the tenon on the stretcher, has a saw kerf cut down it across its diameter. The wedge is then placed into the kerf once everything is glued up, and the joint assembled and driven home)

[rmlaws54]

I would get it all steam-damp with hot water and pull apart all the leg joints, then reassemble using traditional glue (which is plant based now not animal based). I'd use spanish windlasses to bind it together while the glue sets. Using old fashioned glue like this means that there is no need to get every last smidgeon of original glue out because it will be bound in when the new hot glue goes in.

But whatever glue you use, remember to have the chair standing on a good flat floor (or use a flat board if the chair is upside down) as you glue it so the four legs will touch the floor properly.

Robert

[newshound]

Interesting. That's never been obvious to me in any of the chairs that I have had come loose, but then I guess they don't come loose!

What do you think of these things like Chair Doctor that are supposed to make stuff swell up and then set? They have worked OK for me in a few things, but I do normally try to clean out the old glue fairly well, and I am pretty good at strapping things up tight either with tourniquets or with multiple luggage elastics while they set.

[rmlaws54]

In some chairs, where the holes in the elm seat go righ through, you can see that kind of wedge. But in others I think the motice in the seat don't go all through. Did they sometimes hide a wedge inside the mortice before driving the leg in? That would be neat. I'm talking here about those typical bentwood chairs I suppose.

[John Rumm]

Well possibly - I don't know how commonly its done on modern chairs. I would expect allot of modern stuff might just have a pin nail fired through the side of the mortice and into the tenon.

If it makes the tenon swell, then its kind of doing a similar thing (although without the undercut in the mortice, you don't get quite the same mechanical lock).

[John Rumm]

Yup, exactly (pretty much what is shown in the last photo on the wiki page). The wedge bottoms out in the mortice, and then as you drive the tenon home, it spreads itself on the wedge. So once in, its locked in place.

[Nick Odell]

I'm interested in your remarks about traditional glue. I've been using hot hide glue for decades now and - probably because I still have a mountain of pearls in stock and haven't needed to buy any for ages - I hadn't noticed that it's plant-based now.

What's it like to use? Does it have the same/similar properties as hide glue eg, self-clamping and adhesive properties that vary according to dilution? Does it keep as well or better? I know when not to reheat a pot "one more time" and wondered if the vegetable glue gives off the same sorts of clues about its condition.

Thanks,

Nick

[Brian Reay]

Good advice, as is the epoxy. If you can, drill a small cross hole and add a small pin/nail to hold while the epoxy sets. Drill from the underside and it doesn't show. A couple of belts or rope will act as clamps, if you don't have a proper clamp.

[newshound]

Pearls! Wow that takes me back. My grandfather who died in the 1950's had some in his workshop. My father was less of a carpenter, but I remember him using it a few times in the 1960s. I can still recall the smell!

I still have a large wooden plane that my grandfather was supposed to have made, but I havn't used it for 30 years.