Fixing a poor Balloon Back chair glue repair

[Fuzzie]

A friend of mine who likes his antique furniture had previously had repair work done on some balloon back chairs. The top of one has come loose again and I have offered to try and fix it. :console:

The last repair was reportedly done by a 'professional' restorer. I was hoping hide glue had been used, but when the top was fully removed it looks like some new dowels were attempted to be glued in using a lot of PVA. It doesn't soften or dissolve with hot water.

I'm wondering what the best approach to take now is. I can scrape the visible PVA off the end grain but the dowels look to be a loose fit in the holes and I'm guessing clearing out the holes will be problematic.

Any suggestions on how to proceed? First getting the old glue out and secondly filling the gaps around the dowels when they go back in? What are the gap filling properties of hide glue?

[markharrison]

Some pictures would be helpful.

If the dowel is solid in one end of the joint. I would just leave it. Clean out the other hole of glue. I would even consider using the next size larger drill bit to get back to bare wood then upsizing the dowel by gluing on shavings with hide glue to fit the enlarged dowel hole. Hide glue has almost no gap filling properties without additives. It is almost water thin.

According to the Hide Glue book by Stephen Shepard (which I am consulting right now);


Fillers are sometimes added to hide glue to thicken it for various applications. It can be as simple as adding some chalk (calcium carbonate) to slightly thicken to fine sawdust or wood flour for making a filler with the consistency of putty. Minerals such as gypsum, plaster of Paris, marble dust (also calcium carbonate), mica, quartz etc. can also be mixed with hide glue. Bone flour can be added to hide glue to thicken for applications requiring gap filling and production assembly.

I have no idea where you would buy bone flour (AKA bone meal) from. It would be a technique I would personally be testing before using anyway. I think wrapping a wood shaving around the dowel using hide glue would probably be simpler. If it is too thick, you can always resize with sand paper until you get a snug fit.

[Fuzzie]

Some pictures would be helpful.


Ah yes, I resized them but forgot to attach to the original post. :doh:

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[auscab]

Gap filling with hide glue is a very bad choice . Adding fillers to it may help a little but not a lot is what I think . I’ve never used fillers with hide glue in a situation like that . Try it and see ? I’ve seen a lot of hide glue failures , mostly older work that’s come in for repair . But also my own work that I’ve held onto . It’s fantastic glue but not for gaps .
The best way for it to hold is with two pack . You can add oxide colours and it’s a hard putty at the same time if it’s needed . Clamping something like that can be hard . Rope or the elastic bandage I showed in a thread a little while back can hold things right . Another good way for holding that can be the brown packaging tape . Balloon backs were a dumb chair idea in the first place . They get weaker with each repair and they break easily .

[Fuzzie]

Thanks Rob and Mark. I've just discovered metho softens PVA enough to be able to scrape the faces of the joints clean. Having done that I can now see one of the uprights has been filled/repaired with epoxy and the dowel holes redrilled. I think the holes in the arch were purposely left sloppy in order to get things to align during glue up. Tthe dowels used did not have a bleed groove so I guess everything just pistoned down during glueup which didn't help with the final seating of the parts.

I'm working on making things align now. Maybe epoxy is the way to go then.

[Christos]

Personally I like the idea of the dowels been used. I would clean up the holes and glue it back on. As stated the problem is the clean up might make the dowel holes bigger.

Before you start trace the holes on the other end, clean the holes, patch the holes, then drill out the holes using the trace.

This is going to be time consuming and slow.

The other idea is the pack the clean out holes with splinters of wood(tooth picks maybe) and adjust until they align.

[Bohdan]

The only glues that will successfully glue to themselves are hide and epoxy.

If there is any old PVA is left on the original joint then any new PVA will simply be a gap filler.

Any joint that is reglued without removing ALL old PVA is doomed to fail.

You are much better off removing the original dowels, redrilling the holes larger and then using new dowels with epoxy with a sloppy fit for alignment.

[Fuzzie]

The current holes are out of alignment. Here is a pick of the joint cleaned and reseated on the existing dowels. One side is misaligned more than the other.
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I'm pretty sure my ability to drill new holes all in the right direction into endgrain would be found wanting. I could probably more successfully elongate the existing holes in the direction I want the arch to move and fill the resulting void with epoxy.

[Xanthorrhoeas]

Unfortunately, balloon-backs, as well as being ugly (I agree, an unnecessary value judgement) are structurally unsound. Use the epoxy (I will forever be damned!) But, they are only a balloon back, after all.

[markharrison]

The current holes are out of alignment. Here is a pick of the joint cleaned and reseated on the existing dowels. One side is misaligned more than the other.

I'm pretty sure my ability to drill new holes all in the right direction into endgrain would be found wanting. I could probably more successfully elongate the existing holes in the direction I want the arch to move and fill the resulting void with epoxy.

Does the misalignment only show at the back? That is, the front of the chair looks fine where the chair legs meet the balloon top? If so, you could either leave (it would be no worse than when you received it) or you could trim the legs to match where it meets the balloon top. It looks like there is going to have to be some finish touch ups anyway.

[auscab]

Here Franklin is a two pack special . You can get some clamping tip off the pictures.

Worn gappy glued before dowel joints. Breaks Glued before with Hide glue and broken again means two pack is going to hold things together for the longest period.

See how the brown packing tape is used . If you have ever tried to break the stuff without a blade to help you will know its strength . Its wrapped and stretched to help pull impossible to clamp parts together . The webbing with a stick twists and pulls the top of the back forward if its needed for alignment. And on the right join a steel quick action clamp shifts an out of alignment joint forward . We must have put one on the left after that because it looks like it needs it .
The clamp around the base frame is an old one made in the days these Gents chairs were new

It came in upholstered worn out and loose all over .
we pulled it to bits and started again from that pile of sticks .
That's the whole chair in that picture!
Same clamp techniques we use on Balloon backs.

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Rob

[Fuzzie]

Oooh that looks torturous but a great result! I'm not doing a full rebuild just trying to get the arch back glued on cleanly. I spent part of yesterday cleaning the joints getting things to fit as well as I could. I removed another one of the extant dowels and trimmed 1.5mm off one side of the remaining two so I could pull the faces into line. I'll replace the two I have removed with slightly thinner 8mm ones which are a sloppy fit in the holes that can be filled out with epoxy.

I played around with a few different clamping arrangements and started to get a better understanding of your thoughts Rob! I eventually hit on a fairly simple arrangement that looks like it will work easily for this job given that it is not a full rebuild. I'll take a pic later today when I do the actual glueup!

[Fuzzie]

All glued up!

I haven't used epoxy much and this one from the $2 shop seems a bit runny and has a fairly long set time. I thought the other thing I used it on took about 48hr to harden up satisfactorily.

Knowing how runny it was going to be I tried to be prepared for the squeeze out, so I paused before pushing everything all the way home and cleared the meeting faces using a thin steel bristle from a street sweeper (I've found a few uses for these street pickups recently. I must actually keep an eye out and collect a few more to have a stock on hand.)

When I pulled up the clamps there was the inevitable little bit more squeeze out that smeared on the finish and I had to think quick about cleaning it off before it ran further so I grabbed a rag and dosed it in Turps to wipe away the evil bits and realized straight away I had grabbed the Kero bottle rather than the Turps. :frustrated:

This turned out to perhaps be a good thing. The Kero seemed to take off the epoxy without overly affecting the finish. I'm sure Turps would have been worse and as I found when softening the PVA with metho, that would have been a definite no no to use!

I think I'll leave the clamps on till Monday.

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