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#1 David Barnert

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Posted 06 May 2007 - 12:29 AM

Here's one I haven't seen discussed before (forgive me, Dave E., but I cannot find my copy of your book at the moment).

1980s-era Dickinson Wheatstone 46-key Hayden. I noticed while playing today that one note sounds faintly when I play another note. A little investigation reveals that it happens both on the push and on the pull and that the two notes are adjacently placed around the rim of the action board. I suspected that either one pad was lifting the adjacent pad or air was somehow leaking from one chamber into the adjacent chamber.

I took the end off and opened the action box to have a look. The two pads, while adjacent, were not close enough to each other for physical contact. I could easily convince myself, now that I could see it, that there was no way the movement of one pad was influencing the other. That left an air leak.

I put the action box back together and turned my attention to the reed pan. I removed it from where it fits into the bellows and held it up against the smooth surface of the action board in the correct orientation. Each hole in the action board was nicely encapsulated in its own chamber, none near enough to a partition to consider that one might actually straddle a partition. The chamois gaskets on the tops of the partitions seemed to be intact and in contact with the action board along their whole lengths.

But then I noticed something odd: a bit of a wobble in the way the reed pan and the action board related to each other. Sure enough, when the partition between the notes I was looking at was snug up against the action board, the ones 180 degrees around were flapping in the breeze. When I held it so that those were in contact with the action board, the one I was looking at pulled away from it. I was able to rock the reed pan against the action board as if one of them had a bulge in the middle. At the extremes of travel, there was about a millimeter or two clearance at one end or the other. I then took a straight-edge ruler and held it against the action board and sure enough, it also rocked, demonstrating a bulge in the action board.

action_board.jpg

Then I got onto the internet and googled my way to a page in DoN Nichols' web site:http://www.d-and-d.c...nas/tuning.html that includes this paragraph (what I have been calling the "action board," he calls the "valve-board"):

If you hear a second note join the first above a minimal pressure on the bellows, the problem is cross-partition leakage. You can frequently spot where this has been happening by a darkening of the leather seal on the partition top, where airborne dirt has been deposited. The probable cause here is one of the corner blocks from the bellows frame. If the glue holding it has weakened, it will no-longer support the corner of the reed-pan, allowing it to warp away from the valve-board. Finish breaking it away if it shows any movement, clean off all old glue, and re-glue it. Try to glue it in a position so it properly supports the reed pan level with the edge of the bellows frame. If you cannot be precise, here, err on the side of too little support. You may than add small thicknesses of cardboard (such as that from a Kleenex box) until the level is correct. The cardboard alone will do if the block is securely mounted, but not at a sufficient height.

Interesting, but not really my problem. My corner blocks are firmly glued in place (I took it apart again and checked, that's when I took the picture), and I don't think the cardboard trick (while ingenious) will solve my problem of fitting a flat reed pan to a bulging action board.

I expect I could treat the symptom by thickening the chamois gasket over the offending partition, but does this solve the problem? Are my action boards warping? Will it get worse? Are they supposed to be that way? Is there something I can/should do about it?

Any help appreciated.

#2 malcolm clapp

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Posted 06 May 2007 - 03:05 AM

Last time I had this problem with my D/A Jeffries I reassembed it and put it away for a couple of months and moved from a very dry inland Australian climate back to the coast and, hey presto, problem disappeared, never yet to return! (Never realised how hard it is to play anglo with your fingers crossed!!!)

I don't pretend to have any knowledge of Albany, New York, or its climate, or of the conditions in which your concertina is played or kept, but I'm fairly sure it is a humidity problem (or lack thereof). So not necessarily a quick fix. :(

I seem to recall a number of prior threads on the subject of humidity problems and suggested solutions.

Good luck in solving the problem. I hope it solves itself for you as mine did. :)

MC

#3 David Barnert

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Posted 06 May 2007 - 08:25 AM

I don't pretend to have any knowledge of Albany, New York, or its climate, or of the conditions in which your concertina is played or kept, but I'm fairly sure it is a humidity problem (or lack thereof). So not necessarily a quick fix. :(

I seem to recall a number of prior threads on the subject of humidity problems and suggested solutions.

No lack of humidity here. I wouldn't be surprised if the weather was part of the problem, but I'm not sure how to make it part of the solution. As Mark Twain said, "Everybody talks about the weather but nobody does anything about it."

#4 Greg Jowaisas

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Posted 06 May 2007 - 12:09 PM

An 8" X 8" piece of clear glass can be a good tool to determine flatness or lack there of an a sound board or reed pan. You may be able to determine the irregular area and monitor its possible seasonal shift.

If the warp/irregularity seems permanent and keeps causing problems the appropriate thickness of paper or cardboard shim under the chamber chamois seal may be a remedy.

Best of luck,

Greg

#5 David Barnert

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Posted 06 May 2007 - 01:43 PM

If the warp/irregularity seems permanent and keeps causing problems the appropriate thickness of paper or cardboard shim under the chamber chamois seal may be a remedy.

Thanks. By "under the chamber chamois seal" do you mean between it and the sound board or between it and the reed pan?

#6 Greg Jowaisas

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Posted 06 May 2007 - 01:53 PM

Dave,
I mean a paper/mattboard shim under the existing chamois of the reed pan chamber seals. (the thin spokes which run from the center of a radial layout or the thin parrallel walls on some anglos.)
Paper/ mattboard will taper easily for transitions. Keep the glue to a minimum.

Good luck,

Greg

Edited by Greg Jowaisas, 06 May 2007 - 01:54 PM.


#7 Wally Carroll

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Posted 06 May 2007 - 02:50 PM

Dave,
it is not uncommon for the action board to be warped. This is caused by the leverboard being glued directly on top of it which causes an imbalance from one side of the board to the other in how moisture is absorbed and released. A general principle in woodworking is that you always do to one side of a board what you do to the other. Traditional concertina construction violates this principle as it wouldn't make sense to glue an opposing leverboard on the underside of the actionboard to counterbalance the one on top. The good news is that some warping is usually not a problem as the boards are thin enough to be straightened out when the instrument is bolted together. In fact, the leak you are experiencing may have nothing to do with this warping as it very well may be occurring on the sides of the reedpan and not on top. Seasonal changes in humidity can cause the reedpan to move just enough to cause a small gap to occur between the sides of the walls on two adjacent chambers.

If this is the case, you might be able to solve the problem by roughing up the chamois a bit on the sides of the bellows frame. If this doesn't work, try shimming under the chamois with something thin like paper or masking tape.

-Wally

#8 hielandman

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Posted 06 May 2007 - 04:12 PM

Hello. My first comment relates to the corner blocks. What Don Nichols was saying was that if they shifted, they don't have to be broken off, there is glue creep that occurs when a glued joint in under any pressure at all(though in 99 % of the time it may not be noticeable, or manifest itself in the way of a problem)All it has to do is creep down a hair over time, and there is a possiblity of this occuring, thereby losing their supporting value. Check them with a combination square, making sure they are all the same distance from the top edge of the bellow frame. That will tell you if the corner blocks are the problem. Next ...

This same situation happened to me on the second to last Lachenal I restored(Greg Jowaisas just retuned it, and I can't wait to get my hands on it!). I think Dave Elliot refers to the problem as Ghost Notes(I had my book handy when this happened!). My ghost notes weren't due to the blocks slipping, but they were there nonetheless. My action board was so warped(it had been off of the conecertina for quite a while) that there was air seeping in from both the 12 o'clock point, and the six oclock point(assuming your hands are facing 3 and 9) What I did to remedy the situation was to put the action board on the corner of a work table(this is assuming you have a work table and necessary clamps), shim up the 3 and 9 oclock sides about 3/32(.093) of an inch or so, and clamp down the 12 and six oclock ends. I then brushed over the whole assembly with water, which seeps in and relaxes the glue and wood somewhat. I left it that way for two days, making sure everything was thoroughly dry before I undid the clamps. Presto, that did the trick. Just make sure you don't over water it, better to do it in stages, as was said before, err on the side of caution and take a little more time to get it done. I believe I covered it with plastic for a while, so as to "sweat" the wood a little. Good luck, this will work for you,
Don

Edited by hielandman, 06 May 2007 - 09:12 PM.


#9 d.elliott

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Posted 06 May 2007 - 04:44 PM

Brave Man!

Dave

#10 hielandman

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Posted 06 May 2007 - 09:11 PM

Thank you Dave!
I didn't really consider it being particularly brave, I would have straghtened out any warped piece of wood the same way, really. I've done banjo, mandolin, and guitar necks in a similar fashion many times over the years(the difference with them being I was applying heat from an alcohol lamp, or steam instead of water), but the clamping in the opposite direction of the warp being the same. In precision metal fabrication we do that sometimes also(well, I guess I don't anymore, working as a teacher these days), but it is called "benching"(I never quite understood the name of the operation), though it doesn't involve heat, water, or steam, just clamps and/or hammers, in the right places, to remove warps, curves, and other forms of distortion. So I guess I am not the average case, having done a lot of similar things. I can see how that would be scary to many people, though! If Dave Barnert wants help with this, I will be in East Durham in three weeks, of if necessary, I could help him sooner, not living all that terribly far away. Driving from here to Albany is a pleasant drive.

Don

#11 asdormire

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Posted 06 May 2007 - 09:19 PM

Thank you Dave!
I didn't really consider it being particularly brave, I would have straghtened out any warped piece of wood the same way, really. I've done banjo, mandolin, and guitar necks in a similar fashion many times over the years(the difference with them being I was applying heat from an alcohol lamp, or steam instead of water), but the clamping in the opposite direction of the warp being the same. In precision metal fabrication we do that sometimes also(well, I guess I don't anymore, working as a teacher these days), but it is called "benching"(I never quite understood the name of the operation), though it doesn't involve heat, water, or steam, just clamps and/or hammers, in the right places, to remove warps, curves, and other forms of distortion. So I guess I am not the average case, having done a lot of similar things. I can see how that would be scary to many people, though! If Dave Barnert wants help with this, I will be in East Durham in three weeks, of if necessary, I could help him sooner, not living all that terribly far away. Driving from here to Albany is a pleasant drive.

Don



#12 David Barnert

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Posted 09 May 2007 - 11:21 AM

Morris practice tonight, in preparation for two big gigs this weekend, so it was now or never. I did a temporary fix that is working nicely. I simply covered the one chamois gasket that was leaking with a few thin strips cut from the sticky end of a post-it note.

I cut each strip a little shorter than the one under it so the dam tapers toward the center of the instrument, where there is presumably better contact between the reed pan and the action board.

#13 m3838

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Posted 09 May 2007 - 01:32 PM

it is called "benching"(I never quite understood the name of the operation),


I guess it's because the object is clumped to a "Bench", or Workbench, or whatever it's proper name is. It's where wood work is usually done.
But why then Concertina insides are not sealed and laquered?
The better quality accordions have it laquered and I don't recall any humidity problems due to wood expantion. No creaking, opening gaps etc.
Is it because of extra work or sound considerations?
The books teach that prior to boarding a house exterior, the boards must be sealed on all 4 sides immediately after cutting, so the water doesn't seep in. It's not done commonly, but it's better to pay extra for it, than to pay mega-extra for re-boarding in 5 years + water damage to the house.
Are violins and guitars sealed inside?

#14 Alan Day

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Posted 09 May 2007 - 05:03 PM

It is worth checking the little triangular pieces of wood that the reed pan sits on.Sometimes these come unstuck and can cause leakage on the felt section,because the reed pan is sitting lower in that corner.These little bits of wood also fall into the concertina and can stick up reeds or cause buzzing when the bellows are compressed. Also if these bits of wood are not accurately made they can also create buzzing on the reed nearest to them when the bellows are compressed.This is rare ,but I have found a few concertinas with this problem in the past.
Now this warping interests me,it may be a problem that is likely to happen at any time.I am so worried about it, a trip to a warm part of America with my concertinas may put my mind at rest.
Al
Edited to say that this point has already been made.My wrist is slapped accordingly.

Edited by Alan Day, 09 May 2007 - 05:07 PM.


#15 hielandman

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Posted 10 May 2007 - 10:29 AM

David,
good fix, what ever works, right? There is more that one way to skin a cat, eh? (do people still use that expression?)

Take care, and good luck, and good gigs,
Don

#16 Alan Day

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Posted 10 May 2007 - 11:29 AM

Morris practice tonight, in preparation for two big gigs this weekend, so it was now or never. I did a temporary fix that is working nicely. I simply covered the one chamois gasket that was leaking with a few thin strips cut from the sticky end of a post-it note.

I cut each strip a little shorter than the one under it so the dam tapers toward the center of the instrument, where there is presumably better contact between the reed pan and the action board.


A piece of felt cut to width and feathered to go to the centre with a razor blade or what I use a cut throat razor will do the job properly.
In passing ,at a gig one of my pads fell off by coming unstuck from the arm. using a thin peice of elastoplast (for cut fingers etc) wrapped over the end of the arm and fixed either side on the pad,it worked so well it was still there a month or so later,when I remembered to do the job properly.
Al

#17 David Barnert

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Posted 10 May 2007 - 09:56 PM

It is worth checking the little triangular pieces of wood that the reed pan sits on.Sometimes these come unstuck and can cause leakage on the felt section,because the reed pan is sitting lower in that corner.

Yes, I considered and rejected that possibility in my original post:

The probable cause here is one of the corner blocks from the bellows frame. If the glue holding it has weakened, it will no-longer support the corner of the reed-pan, allowing it to warp away from the valve-board...

Interesting, but not really my problem. My corner blocks are firmly glued in place...

In passing ,at a gig one of my pads fell off by coming unstuck from the arm. using a thin peice of elastoplast (for cut fingers etc) wrapped over the end of the arm and fixed either side on the pad,it worked so well it was still there a month or so later,when I remembered to do the job properly.

Before I got my Wheatstone, when the only concertina I had ever taken apart was my Bastari Hayden, a friend's Wheatstone English developed a stuck note and he asked for my help, as we were traveling and couldn't get to a proper repair place. I took it apart and received a real education. The concept of a radially arranged pan with all reeds in the same plane was a complete surprise. When I got the action box open I discovered his problem: a pad had come unglued from its lever. I didn't have any glue to fix it (and had no idea what kind to use) so I asked my friend if he could do without that note until he could get it repaired. He said yes, so I removed the pad, gave it to him for safe keeping, and took some (yes, like Alan) elastoplast and covered the hole in the sound board. I should have tried it Alan's way.

#18 d.elliott

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Posted 15 May 2007 - 03:55 PM

Thank you Dave!
I didn't really consider it being particularly brave, I would have straghtened out any warped piece of wood the same way, really. I've done banjo, mandolin, and guitar necks in a similar fashion many times over the years(the difference with them being I was applying heat from an alcohol lamp, or steam instead of water), but the clamping in the opposite direction of the warp being the same. In precision metal fabrication we do that sometimes also(well, I guess I don't anymore, working as a teacher these days), but it is called "benching"(I never quite understood the name of the operation), though it doesn't involve heat, water, or steam, just clamps and/or hammers, in the right places, to remove warps, curves, and other forms of distortion. So I guess I am not the average case, having done a lot of similar things. I can see how that would be scary to many people, though! If Dave Barnert wants help with this, I will be in East Durham in three weeks, of if necessary, I could help him sooner, not living all that terribly far away. Driving from here to Albany is a pleasant drive.

Don



Don,

Very brave for the following reasons:

1. It may not have been warpage that was the full cause of the problem
2. the reed pan chamber walls and gaskets are all hydroscopic and are also held together by water soluble glues
3. as an aerospace engineer we had to bench all machined components for dressing and certain stress management purposes, but as you know, good old wood does not work the same way as metalic materials
4. you may well have re-introduced an in-stability back into a stable if warped structure.

as I said very, very, very brave; I am glad ir worked out for you.

I would have adjusted pan height blocks and chamber gasket packings to make the system work

Dave E




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