Messed up hook and loop ina Lachenal

[apprenticeOF]

I'm working on an older Lachenal (circa 1870) and have encountered a problem with a poorly done previous repair. It appears that in trying to set the key heights, someone has loosened all the loop pegs from the action board. Most of them just pop out when putting the springs in place.

 

The pads are obvious replacements (two were glued to the action board) and I'm guessing that instead of bending the arms, someone has attempted to set the key height by pulling the loops up.

 

My plan is to gently serrate the tangs on the loops, and tap them down into the board using a small amount of epoxy.

 

Would appreciate any comments on this proposed repair, or any better alternates.

[Alex West]

Apprentice

 

I'm doing something similar at the moment with somewhat the same issues. You might be right about the key heights, but I think in my case, the wood has been so dry that in the ageing process, the holes have simply become bigger and the loops therefore looser in their slots. Your approach sounds OK as a fix - simply serrating the loop ends might also be sufficient to increase the mechanical grip of loop to wood; a dab of superglue would work just as well as epoxy and be slightly less messy

 

Alex

[from the workbench]

I'm working on an older Lachenal (circa 1870) and have encountered a problem with a poorly done previous repair. It appears that in trying to set the key heights, someone has loosened all the loop pegs from the action board. Most of them just pop out when putting the springs in place.

 

The pads are obvious replacements (two were glued to the action board) and I'm guessing that instead of bending the arms, someone has attempted to set the key height by pulling the loops up.

 

My plan is to gently serrate the tangs on the loops, and tap them down into the board using a small amount of epoxy.

 

Would appreciate any comments on this proposed repair, or any better alternates.

 

- The early lachenal instruments do not have serrations on the pivot pressings. Alex is right, the problem you have experienced is due to shrinkage of the action board. The solution is to do what Alex advises ----but do not ever use epoxy or super glue for simple tasks like this. It is only neccessary to press the pivots into their original holes with the assistance of a little serration of the tongue of the pivot pressing.Do this gently with some side cutting pliers (If you use too much enthusiasm you will overharden the brass and finish up with two small pieces of scrap)

A toothpick point of hide glue (you can use Franklins liquid hide glue for this job)will be sufficient to hold the pivot in place. to avoid damaging the pivots use a pair of jewelers flat nosed pliers to hold the pivot (one jaw in the slot and the other on the side of the pivot)and then press it in carefully. No hammer should be required.

If you have less than 55% humidity where you are storing this instrument,expect more trouble.

[Theo]

If the post are still loose, even with serrations then place a thin sliver of wood vertically in the hole before inserting the tang of the pivot post. This should give you a nice tight fit, and is much preferable to using a permanent glue.

[Leonard]

- The early lachenal instruments do not have serrations on the pivot pressings. Alex is right, the problem you have experienced is due to shrinkage of the action board. The solution is to do what Alex advises ----but do not ever use epoxy or super glue for simple tasks like this. It is only neccessary to press the pivots into their original holes with the assistance of a little serration of the tongue of the pivot pressing.Do this gently with some side cutting pliers (If you use too much enthusiasm you will overharden the brass and finish up with two small pieces of scrap)

A toothpick point of hide glue (you can use Franklins liquid hide glue for this job)will be sufficient to hold the pivot in place. to avoid damaging the pivots use a pair of jewelers flat nosed pliers to hold the pivot (one jaw in the slot and the other on the side of the pivot)and then press it in carefully. No hammer should be required.

If you have less than 55% humidity where you are storing this instrument,expect more trouble.

 

Welcome from the Workbench to this forum....

 

You seem to be less new to the concertina than you are to this forum. Would you mind introducing yourself?

 

Leonard.

[apprenticeOF]

Thanks for for the input folks.

 

Yes, the climate is relatively dry here in the wine country of the Okanogan valley. Good point. In this case, though, the concertina came to me from the east coast with the problem. I will, however, delay working on the problem for a couple of weeks and let the 'tina acclimatize.

 

My plan now is to use Theo's suggestion of wood slivers - plus gentle serration, although I will use just a smidge of liquid hide glue (I use Tite Bond brand) to hold the slivers. I will make sure to use a contrasting wood color (I'm thinking Phillipine mahogany as it's fairly soft) so that the shims can be identified for future removal/replacement (if necessary).

 

The reasoning for the tiny bit of hide glue is that the only way I can think of to make such small shims is to shave them with a sharp knife, which will leave smooth surfaces that will work against holding strength.

 

Thanks again.