Replacing chamois gasket

[OLDNICKILBY]

I will repeat but not, repeat NOT recomend a solution to leaks.

I was offered a lovely Duet and the owner boasted that he had "Cured the leaks" with what was my retort "Oh Araldite " he replied "I glued it all together"

[Johanna]

So I finally worked up the courage to have a go at this. I think it worked well. But now I have a few more questions:

 

- How do I keep the edge of the chamois from showing out the edge between the action box and the bellows frame? If I were replacing the leather on the bellows frame, I could cover it with that, but what if I'm not?

 

- What is the best way to make the holes for the end bolts to go through? What I did was (after the chamois was already glued in place) pierce small holes where the bolts should go, then enlarge them by working the bolts through them. Should I have done something else?

[Greg Jowaisas]

Sounds like you used common sense and did just fine.

 

Before piercing the chamois I try and fit the ends and push on the endbolts. The impression left by the tips of the endbolt tells me where to pierce. Always err to the inside of the chamois so the end bolt has an adequate seal all around.

 

Black "Sharpie" carefully applied and allowed to dry can hide any visible blonde chamois.

 

Greg

 

PS. I regularly inspect the chamois in the auto supply department of my local Target Department Stores to find the best uniform chamois.

[Johanna]

Thanks, Greg. I did this on my Lachenal (only one end so far), not the Wheatstone you sold me, but the idea was to see whether it's feasible for me to try it myself on the Wheatstone.

[d.elliott]

I'm in the process of fixing up a Lachenal tutor EC that I bought off eBay. So far, I've replaced about half the valves (the ones that were stiffest or most curled), replaced one pad (that was misaligned to begin with and wasn't sealing at all), patched a few small holes in the bellows, and reglued one of the pillars that had come loose. I've been doing all this a bit at a time, which means I've removed and replaced the ends several times. The chamois gasket was worn very thin when I got it, and doesn't seem like it will last much longer. It still seems to be making a reasonably good seal, but I don't know how much more "roughing up" it can take. So I suppose I'll need to replace it at some point. I've been following Dave Elliott's maintenance manual, but this doesn't seem to be covered in there. And so I have questions.

 

1. I gather from other threads here that any old chamois will work, but thicker is better? Any particular thickness I should be aiming for?

 

2. How exactly do I do this? How do I figure out what size and shape to cut, how do I fit it into place, what kind of glue should I use, etc.? I've been looking around for instructions, but haven't found any. I guess it might be easy to figure out, but I don't want to take the old gasket off only to realize that I have no idea what I'm doing.

 

3. The chamois strips along the partitions between the reed chambers seem to be in good condition, but it looks like if I replace the worn-out outer gasket with something thicker, the inner strips will no longer be high enough to make a good seal. Is that a reasonable suspicion? What do I do if that happens?

 

4. Anything else I need to be careful about?

 

Thanks in advance for your help.

 

 

looking at this thread, I am reminded about the engineering decision taken when York Minster caught fire after a lightening strike about 25 years back.

 

The engineers needed to re build some of the main roof structure which had been in place since the Norman conquest, the question was, what material should we use that will be as least as good as the original? The original was Oak Beams.

 

The universities and learned societies all came the the same endpoint decision the only substance they could guarantee would perform for 1000 years, was not stainless steel, nor composite , nor carbon fibre or this that and the other, but the humble oak, because it just had lasted 1000 years, until an act of God.

 

So when looking at the bellows frame gaskets, most of which I see have lasted largely quite well for in excess of 100 years, some 130 years, most over 80 years; the only material I could guarantee is, Chamois., why - because it just does, there is no risk it just works.

 

If this principle works for a restoration of damage to a Minster founded in 640 AD and re built in 1080AD, then it works for me when applied to the equally venerated, but more humble concertina..

 

Sorry I have not included chamois in the Maintenance book, I saw the replacement of the chammies as more a restoration exercise than one routine maintenance and servicing. Now the restorer's manual would include this sort of thing, if I ever finish it.

 

 

Dave

[Johanna]

Sounds like you used common sense and did just fine.

 

Apparently, I don't have nearly as much common sense as you give me credit for - I was just closing up the other end of the Lachenal after replacing its gasket, and I managed to snap an end bolt through overzealous tightening. So now I have to find my way out of this mess. But for right now, I'm going to sleep.

[d.elliott]

Sounds like you used common sense and did just fine.

 

Apparently, I don't have nearly as much common sense as you give me credit for - I was just closing up the other end of the Lachenal after replacing its gasket, and I managed to snap an end bolt through overzealous tightening. So now I have to find my way out of this mess. But for right now, I'm going to sleep.

 

Oh dear,

 

what glue did you use on the chamois gasket?

 

Dave

[Greg Jowaisas]

Sounds like you used common sense and did just fine.

 

Apparently, I don't have nearly as much common sense as you give me credit for - I was just closing up the other end of the Lachenal after replacing its gasket, and I managed to snap an end bolt through overzealous tightening. So now I have to find my way out of this mess. But for right now, I'm going to sleep.

 

Snug is good. Tight is alright. Torqued down gets a frown.

 

Let us know where the endbolt sheared off and we will advise.

 

Greg

[Johanna]

Snug is good. Tight is alright. Torqued down gets a frown.

 

Let us know where the endbolt sheared off and we will advise.

 

Greg

 

It sheared off just at the tip, where it enters the rectangular nut under the chamois. I've removed the nut from the end frame, but I've had no luck in getting the tip of the bolt out of the nut. (I tried to take a picture, but my camera's no good at focusing that small.)

 

Now that I think back, it's possible (dare I say it?) that I may have mixed up two of the end bolts. Could that have caused this? (I didn't think I was tightening the bolt any more than I usually do.) If so, is there anything I can do to guard against the other one breaking too?

[Johanna]

Oh dear,

 

what glue did you use on the chamois gasket?

 

Dave

 

I've been using PVA, in the form of ordinary white school/craft glue.

[Greg Jowaisas]

Snug is good. Tight is alright. Torqued down gets a frown.

 

Let us know where the endbolt sheared off and we will advise.

 

Greg

 

It sheared off just at the tip, where it enters the rectangular nut under the chamois. I've removed the nut from the end frame, but I've had no luck in getting the tip of the bolt out of the nut. (I tried to take a picture, but my camera's no good at focusing that small.)

 

Now that I think back, it's possible (dare I say it?) that I may have mixed up two of the end bolts. Could that have caused this? (I didn't think I was tightening the bolt any more than I usually do.) If so, is there anything I can do to guard against the other one breaking too?

 

I've had success with a tip learned from Wally Carroll. Use a hard (abrasive) eraser pressed against the bolt shard lodger in the set (nut). Counterclockwise turning of the eraser sometimes unscrews the shard enough to allow pliers or a small vice grip to finish the job. Sometimes heat drom the tip of a soldering iron can loosen things up enough for the eraser to do its trick. Try this before drilling out the set. Drilling often damages the threads.

 

Another bolt and set can probably be obtained from Mark at concertina spares.

 

Best of luck,

 

Greg

[apprenticeOF]

To prevent mixing up the end bolts, a scrap of wood with holes drilled and numbered is useful. I use one marked with rows Left and Right just to be even more careful. It might be overkill but I extended the row of holes to accommodate the sundry screws from thumbstraps etc. so that every screw and bolt goes back in its original home.

 

Plus, because I'm a boater, I use 6mm green color code dots (Avery) on larger components from the right side, red ones for components from the left (placed in spots where the tiny bit of residue won't matter). This also might be overkill, but I find it helpful.

 

If you get really stuck Concertina Connection offer new bolt/plate combinations - the threads are different and the heads a bit more squared off.

[SteveS]

To prevent mixing up the end bolts, a scrap of wood with holes drilled and numbered is useful. I use one marked with rows Left and Right just to be even more careful. It might be overkill but I extended the row of holes to accommodate the sundry screws from thumbstraps etc. so that every screw and bolt goes back in its original home.

Very good tip.

I use the top of a breakfast cereal box and punch holes through it for the various screws - mark off the left/right and which bolt is nearest the label or thumbstrap.

I also use plastic food containers with lids (like used for home freezing) to save other various bits I might take off a 'tina, marking their positions and orientation for correct re-assembly.

[Johanna]

To prevent mixing up the end bolts, a scrap of wood with holes drilled and numbered is useful. I use one marked with rows Left and Right just to be even more careful. It might be overkill but I extended the row of holes to accommodate the sundry screws from thumbstraps etc. so that every screw and bolt goes back in its original home.

 

Plus, because I'm a boater, I use 6mm green color code dots (Avery) on larger components from the right side, red ones for components from the left (placed in spots where the tiny bit of residue won't matter). This also might be overkill, but I find it helpful.

 

If you get really stuck Concertina Connection offer new bolt/plate combinations - the threads are different and the heads a bit more squared off.

I had a system for telling the bolts apart. But then I knocked it over. D'oh.

 

Thanks for the note about Concertina Connection. I had asked at the Button Box, but they said they didn't know if they had any nuts/plates/inserts.

[jrintaha]

I made a template for cutting nice chamois gaskets for a standard-size instrument. I thought the time spent on the template would pay itself back many-fold, since I have more than one box which could do with replacement gaskets.

 

I measured the circumference of the outer side of the bellows frame, added some extra, and used that as the length for a test strip of chamois; then I estimated how wide the strip should be, added some extra; then I folded the chamois on the bellows frame as nicely as I could, used a tiny drop of casein glue to affix the chamois strip in a couple of places so it wouldn't fall off immediately, then trimmed the edges and dotted the places for the end bolt holes. Then I removed the chamois, pierced the holes, tried to fit it again, trimmed it again, and when I was satisfied with the fit, I made a template out of it and cut another piece of chamois with the template. Now I had nice new gaskets and a nice template for making more.

 

Then I lost the template.

[d.elliott]

To prevent mixing up the end bolts, a scrap of wood with holes drilled and numbered is useful. I use one marked with rows Left and Right just to be even more careful. It might be overkill but I extended the row of holes to accommodate the sundry screws from thumbstraps etc. so that every screw and bolt goes back in its original home.

 

Plus, because I'm a boater, I use 6mm green color code dots (Avery) on larger components from the right side, red ones for components from the left (placed in spots where the tiny bit of residue won't matter). This also might be overkill, but I find it helpful.

 

If you get really stuck Concertina Connection offer new bolt/plate combinations - the threads are different and the heads a bit more squared off.

I had a system for telling the bolts apart. But then I knocked it over. D'oh.

 

Thanks for the note about Concertina Connection. I had asked at the Button Box, but they said they didn't know if they had any nuts/plates/inserts.

 

I get all my nuts & bolts from concertina spares, when I don't have a scrap instrument to pillage that is.

 

Dave