Treble key rods contacting register block

[debra]

Yes, I suppose I could try that. Maybe a little spot Dremel grinding on the register block (removed from the box, of course). I’ve been hesitant to make permanent changes, but I think that’s a small enough change that it wouldn’t be too bad.

For the picture where the arm is hitting the pin behind one of the register switches, do you think I can shorten the pin a tiny bit (cut a little bit off) without risking failure of the switch? I tried to file the pin a bit to shorten it and soften its edges, but without much success. I have a feeling it will poke through the duct tape in only a short time and the clicking will be back for that key.

It doesn't look like the end of the pin serves any purpose, so I'd just grind it down by 2mm or thereabout.
But another approach to the problem entirely would be to check whether when the accordion is fully reassembled the register mechanism is actually sitting in the right position. Assuming the accordion must have worked correctly when it was new some "abuse" may have caused the whole mechanism to go down a bit (closer to the keyboard levers) and could be raised up by maybe 2mm to alleviate the problem without bending or removing anything on the keyboard itself, just on the supports of the register mechanism. I have often seen people place folders with music, or even a folded-up music stand, on the treble side, when putting the accordion in its carrying case. Repeated small bumping or pressure on the register mechanism can damage it over time and push it down.

 

[Dingo40]

Good thinking, Paul!
Another thing about pins: often they can be fitted in reverse, which could avoid shortening?

 

[AlicePalace]

It doesn't look like the end of the pin serves any purpose, so I'd just grind it down by 2mm or thereabout.
But another approach to the problem entirely would be to check whether when the accordion is fully reassembled the register mechanism is actually sitting in the right position. Assuming the accordion must have worked correctly when it was new some "abuse" may have caused the whole mechanism to go down a bit (closer to the keyboard levers) and could be raised up by maybe 2mm to alleviate the problem without bending or removing anything on the keyboard itself, just on the supports of the register mechanism. I have often seen people place folders with music, or even a folded-up music stand, on the treble side, when putting the accordion in its carrying case. Repeated small bumping or pressure on the register mechanism can damage it over time and push it down.

Hmm, this is an interesting thought. I agree, it can’t have had this problem when it was new. And for sure it had to have suffered abuse, as it was a student model (still has the music school sticker on it). I’ll have to take a look to see if it got bent somehow. The mechanism works smoothly and correctly, and there is only one set of screw holes, but perhaps it collapsed just a little bit. I’ll let you know what I find.

 

[AlicePalace]

Is it working now?

Yes, it is working just fine and the two keys in question are not clicking. As for the third key that was a bit noisy — I do think that problem is the felt padding, so I’m just going to live with it. It only make noise if I play it *just so*, so … I will try not to play it like that.

 

[AlicePalace]

It doesn't look like the end of the pin serves any purpose, so I'd just grind it down by 2mm or thereabout.
But another approach to the problem entirely would be to check whether when the accordion is fully reassembled the register mechanism is actually sitting in the right position. Assuming the accordion must have worked correctly when it was new some "abuse" may have caused the whole mechanism to go down a bit (closer to the keyboard levers) and could be raised up by maybe 2mm to alleviate the problem without bending or removing anything on the keyboard itself, just on the supports of the register mechanism. I have often seen people place folders with music, or even a folded-up music stand, on the treble side, when putting the accordion in its carrying case. Repeated small bumping or pressure on the register mechanism can damage it over time and push it down.

Externally, here is what the registers look like. They don’t seem to be shifted left/right at all. They seem very close to the top of the opening in the grille, and perhaps they are supposed to be like that? If I recall correctly, there wasn’t anything obvious inside that looked bent to me. I didn’t see anything out of whack when I removed the register block, either.

 

[debra]

Externally, here is what the registers look like. They don’t seem to be shifted left/right at all. They seem very close to the top of the opening in the grille, and perhaps they are supposed to be like that? If I recall correctly, there wasn’t anything obvious inside that looked bent to me. I didn’t see anything out of whack when I removed the register block, either. ..

Not shifted left or right, but what I meant was pushed down towards the key rods. This happens when you for instance keep a (folded up) music stand inside the accordion case during transport.

 

[boxplayer4000]

I'm a little confused.
Some pallet rods are hitting an object (the coupler bracket) on the upswing.
So, how will adjusting the pallets fix that?
I

Dingo40: Good question. I was expecting it to be taken up. The answer is that the compression of the pallet felt/leather will be more (2 or 3mm is not uncommon) than that lost at the felt or leather stop under the end of the key. Renewing the pallet felt/leather will raise the pallet nearer to the 'obstruction' on this accordion but it will reduce the key outer end travel and the key will 'bottom out' when pressed before the pallet rod engages the 'obstruction'. This is how the accordion was set up in the first place. There's obviously some fine tolerances here; careful selection of pallet/felt thickness choice is important. I would still be hopeful of making a repair without removing the keys to access the felt or leather stops under the key ends.
AlicePalace's picture with the finger pointing at the keyboard axle shows that the C key edge (which is only partly visible due to the blue material) is rising away from the fixed end of the keyboard clearly showing a significant pallet leather/felt compression. In my experience when instruments are new the keys are level with their end frames. A picture showing the outer end of this key would have been helpful.

 

[AlicePalace]

A picture showing the outer end of this key would have been helpful.

Here is a picture without the blue painter’s tape. I’ve indicated the two keys that are having the problem.

 

[henry d]

Dingo40: Good question. I was expecting it to be taken up. The answer is that the compression of the pallet felt/leather will be more (2 or 3mm is not uncommon) than that lost at the felt or leather stop under the end of the key. Renewing the pallet felt/leather will raise the pallet nearer to the 'obstruction' on this accordion but it will reduce the key outer end travel and the key will 'bottom out' when pressed before the pallet rod engages the 'obstruction'. This is how the accordion was set up in the first place. There's obviously some fine tolerances here; careful selection of pallet/felt thickness choice is important. I would still be hopeful of making a repair without removing the keys to access the felt or leather stops under the key ends.
AlicePalace's picture with the finger pointing at the keyboard axle shows that the C key edge (which is only partly visible due to the blue material) is rising away from the fixed end of the keyboard clearly showing a significant pallet leather/felt compression. In my experience when instruments are new the keys are level with their end frames. A picture showing the outer end of this key would have been helpful.

Fine stuff- though as you point out there is no clear indication that the keyboard is out of level- and AlicePalace gives every indication of being more than familiar enough with the instrument to notice same.

A key shaft coming back too far- and the issue for the clacking is either that or a shift in the bracket it is contacting- is unaffected by the thickness of the pallet felt. You could take it off altogether and the key would be way higher than its neighbors and the accordion would of course leak like sin but the shaft would come back no farther.

If you replaced the pallet felt with a thicker pad you'd first have to reset the pallet so that the top part wasn't leaking, and then adjust the bend in the shaft so that the now depressed key became level with the rest of the keys. This would indeed change the travel and probably eliminate the clacking. You'd have to be careful that the key still went down far enough to raise the now thicker pallet sufficiently.

Compression of the felt under the pallet wouldn't cause increased travel with subsequent clacking unless someone at some point had chosen to realign a key rendered too high by the pallet compression by bending the shaft.

The instrument plays fine as is at present, absent an unlevel keyboard or the discovery of a bracket misalignment correctable by a bit of screw loosening adjusting and retightening (and that doesn't seem likely though possible), playing it and enjoying it would to be the way to go for me at least.

 

[boxplayer4000]

henry d:
AlicePalace’s last picture helps to show the compression that the pallet felts have suffered through age and use. In the picture the difference in height at Point 1 (above the key axle approx) looks to be about 2 - 3mm below Point 2.
Re-felting one or two keys only is not recommended. As you suggest it may be possible to make temporary adjustments to remove the immediate problem but I think in the long term the whole keyboard would benefit from overhaul.