Thread: Fixing a deteriorating joint in dining table

I haven't used it but you could give this a try

https://www.carbatec.com.au/joinery-...ml-2oz-veritas

I haven't used that glue before, but reading the description makes me think it's not the right stuff. Swelling a joint is fine if it's completely encased, like a tenon, as it will lock against the mortice, but finger joins need to be properly stuck to each other.

It's widely agreed by tradies that people who try to fix things and then take it to a professional after it doesn't work are basically the worst clients on the planet because we have to un-fix things (which generally involves trying to scrape super glue and who know's what else out of joints) before we can fix it properly - turning what should be a fairly simple task into a half-day ordeal.

Probably budget about $150-200 to repair it now, double it if a DIY repair doesn't work.

Where in Melb are you?

I would like to see images of the underside of the table showing the separation of the fingerjointed rail and the inside joins of the leg.
The rail might easily be fixed, need more info for the leg.

Welcome to the forum Dom.

Originally Posted by elanjacobs

It's widely agreed by tradies that people who try to fix things and then take it to a professional after it doesn't work are basically the worst clients on the planet because we have to un-fix things (which generally involves trying to scrape super glue and who know's what else out of joints) before we can fix it properly - turning what should be a fairly simple task into a half-day ordeal.

Probably budget about $150-200 to repair it now, double it if a DIY repair doesn't work.

Ha Ha !! Love that . I agree with that 100% ! That's the bit about the job costing double and the reasons.


What a ridiculous place for a maker to use a finger jointed board!

Originally Posted by domburke

As you can see from the second picture, the leg closest to this joint is now standing at a pretty significant angle. And as you can see from the third and fourth pictures, the tabletop is dipping a bit too.

I guess my main question is how urgently I should get this repaired? And secondly, how much work can I expect to be involved in the repair and at what cost (obviously just looking for a ballpark figure)?

Thanks in advance.

Dom

The top is whats stopping the finger joint opening up more. That may hang on forever like that ? The separated leg joint is another indication of cheap work and a reason why the table could fall if both legs at the same end are bad. The first thing I would do is look in the gap to see whats there . Also in under the top to see whats at the leg to rail joints . If you could spot a tenon in the gap then its just a bad glue job been done , and may be easy for a pro to fix. If its dowels that are broken or loose because of a bad glue job its harder to fix. And If when you look under the top those legs are joined to the rails by some wizzy metal fitting like Ive seen in cheap table shops then its rubbish.
If it is that
I would like to see the leg taken off and the original seller chased with it buy the first buyer.
When he catches him it gets placed where the sun don't shine!

Rob

It looks to me as though the table was used as a pallet at some point in your house move.

I'm not sure that the failed finger joint can be repaired which would involve shortening both long aprons and remaking the joint.
Which is starting to look like a major rebuild of the table. Doable, but not necessarily inexpensive in set-up time.

Originally Posted by auscab

Ha Ha !! Love that . I agree with that 100% ! That's the bit about the job costing double and the reasons.


What a ridiculous place for a maker to use a finger jointed board!

I've done my share of those repair jobs and some of the things I've seen in the process range from amusing to mind-boggling. If the fingers were longer, say 15-20mm, I reckon it'd be perfectly fine.

Originally Posted by ian

I'm not sure that the failed finger joint can be repaired which would involve shortening both long aprons and remaking the joint.
Which is starting to look like a major rebuild of the table. Doable, but not necessarily inexpensive in set-up time.

The plan I had in my head was to wire brush the fingers and re-glue, then rout out the back of the rail to half the thickness, 100mm either side of the fingers, and glue in a piece to bridge the joint. Invisible from the outside, but still strong enough to sit on and no re-cutting needed.

I love these jobs. Dead easy.

The leg is held on with 2 bolts from the inside in the skirt. The table top itself will be held on with toggles/tabs attached to the top and into the skirt.

There are two fixes.

First, pop off the top by undoing the screws in the tabs, repair the skirt by wiggling it apart and re-gluing it.

Second, the leg is dead easy as the bolts just need tightening up.

Originally Posted by elanjacobs

The plan I had in my head was to wire brush the fingers and re-glue, then rout out the back of the rail to half the thickness, 100mm either side of the fingers, and glue in a piece to bridge the joint. Invisible from the outside, but still strong enough to sit on and no re-cutting needed.

Originally Posted by woodPixel

I love these jobs. Dead easy.

The leg is held on with 2 bolts from the inside in the skirt. The table top itself will be held on with toggles/tabs attached to the top and into the skirt.

There are two fixes.

First, pop off the top by undoing the screws in the tabs, repair the skirt by wiggling it apart and re-gluing it.

Second, the leg is dead easy as the bolts just need tightening up.

I was thinking that, after removing the top, crap within the finger joint would make straightening the apron difficult to impossible to achieve leading to the need to re-cut the joint. But I like Elan's proposed fix by effectively splicing the joint.

in normal use, a finger joint on an apron rail would be plenty strong enough. Only issue I can see is when the table is used as a bridge girder or pallet

I'd plane and glue a bit of wood over the inside of the finger joint , and wire brush the joint too . But if I were going to the trouble of recessing it in then I may as well do a dovetail on each end of that patch. If the client was wanting that and happy to pay.

The thing is though , its an absolutely stupid way to build a table rail . The idiot who built it has only given himself a bad name for a dumb idea.
And if there is one finger joint at the point shown there could be more ?

I don't agree that in normal use a finger joint is strong enough in that rail at all Ian .

Good tables should survive periods of neglect .

Rob

Originally Posted by auscab

I don't agree that in normal use a finger joint is strong enough in that rail at all Ian .

to quote a few sources
"Finger joint lumber is as strong as, or stronger than conventional dimension lumber" http://brink.bc.ca/products/benefits/

"New Zealand finger-jointed pine meets the requirements of New Zealand, Australia , Japanese, USA and British structural testing standards." Structural systems - finger jointed - NZ Wood

"Structural finger joint -- fully interchangable with lumber of the same grade and species" Canadian Wood Council Finger-Joined - CWC

"Finger jointing of beech wood laminations is principally well feasible in industrial conditions when jointing pressure is adequately adjusted as compared to softwood jointing"
"finger jointed beech laminations will foreseeable lead to high strength glued timber beams"
Stuttgart University http://www.mpa.uni-stuttgart.de/publ...r_hoefflin.pdf

"[Finger jointed lumber] is commonly classified by wood specialists as high quality product, because of its desirable properties such as straightness, dimensional stability, and interchangeability with un-jointed lumber and unlimited length" International Journal of Engineering and Applied Sciences (IJEAS), Volume-2, Issue-12, December 2015 https://www.ijeas.org/download_data/IJEAS0212044.pdf (my emphasis)



but totally agree with

Originally Posted by auscab

Good tables should survive periods of neglect .

Rob

Originally Posted by ian

to quote a few sources
"Finger joint lumber is as strong as, or stronger than conventional dimension lumber" http://brink.bc.ca/products/benefits/

"New Zealand finger-jointed pine meets the requirements of New Zealand, Australia , Japanese, USA and British structural testing standards." Structural systems - finger jointed - NZ Wood

"Structural finger joint -- fully interchangable with lumber of the same grade and species" Canadian Wood Council Finger-Joined - CWC ..... etc ......

Yes Ian, but the structural testing is all done soon after the glue cures, and not several years down the track after the wood has been exposed to multiple moisture cycles! I've been mucking about with wood for over 50 years,and if I've learnt one thing, it is that most glue joints will eventually fail. Finger joints have been around for a goodly while now, and despite claims like those you quote, I've seen quite a few that have let go. Most weren't even in load-bearing situations, as far as I could tell, and probably the most consistent cause of failure that I could determine was constant/frequent wetting. But that was for the minority, I have no good idea why others (like that table apron) gave up the ghost. I very much doubt the case illustrated is due to over-loading, after all, if finger joints are as strong as the native wood, why should the apron fail there? Furthermore, that looks to me like a very even, complete glue failure, a fracture due to loading would be wider at the bottom, and probably still hanging by a thread toward the top, and most likely, some of the fingers would have broken, rather than complete glue separation occurring, unless the glue had already deteriorated.

Call me an old-fashioned git, but I would never use finger-jointed members in furniture, partly because of appearance and mostly 'cos I just don't trust them for the long haul. For skirting boards & architraves, inside and heavily painted, yeah, okay (just!)......

Cheers,

It'd be interesting to see the long term performance of new finger joints with PU glue, from what I've read it doesn't break down by any known means