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Seth

My Reed Measurement activities

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I spent several days last week measuring two different 20 button Lachenal’s and as expected the reeds in them were of the same design but oddly they both being 20 button layouts didn’t have the exact note layout.  Anyways that’s for another topic.

 

I noticed pretty quick that there was a set number of identical reed sizes that were used over and over for  few notes and then the size would change for the next few.  I came up with 17 frame sizes, slot lengths matching as well, with 80 reeds from the two sets.  I took the average as they would be a few thousands off from each other and noted the size in the attached chart.  I haven’t gotten around to measuring the tongues but that’s next once I can find my micrometer with the tiny narrow pin to get into the slot.

 

One observation was that regardless of the length of the reed from the shortest to the longest the distance from the Heel to the start of the slot was almost identical in all reeds and the same for the end of the slot to the tip of the reed so I logged them all being the same for CAD drawing purposes.

 

the thing that threw me off a little was the width of the slot, the slot being where the reed tongue swings.  The width of the reeds from around 1 1/4” long or less were from .075 to .085.  There was some variation here but it was small which led me to guess that the original intent for these reeds slot was 2mm to 2.2mm wide.  Now, on to the longer reeds on the Bass side.  These reeds were from .098 to .102 which translates to roughly 2.5mm wide.  This is what I’m wondering what others with reedmaking experience think about as I’m planning to have a set cut on a laser or waterjet. 

 

On to the reed body/shoes overall taper.  I measured the milling jig with the stuff I have that I inherited from Harold Herrington’s workshop and the taper appears to be 5.5 or slightly higher but not over 6.  The Lachenal’s reeds fit perfectly into the slots made on the Herrington jig so hopefully my angle finder read accurately.

 

I don’t know all the terminology yet so please excuse any mistakes in my chart.  Once I get my hands on a set of 30 button reeds or a 30 button set I will be able to update and add more data to the list.  I figured I would add this as I couldn’t find any information like this when I started looking for reed specs.

3BC46A37-26BC-4091-AD8D-473930B0D473.jpeg

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Besides the fact that I’m pretty sure GB had not gone metric when these reeds were designed, keeping the heel distance the same allows consistent use of clamp blocks since the front edge of the clamp block needs to be directly over the start of the reed window to avoid buzzing or other pitch problems.  Consistent tip distance keeps the chamber as short as is practical, while still leaving room  for the flap valve to completely cover the reed port on the draw reeds.  Too short a tip distance puts the end of the port too close to the end wall.  Too long a tip distance in higher notes especially makes the chambers longer than needed which can adversely affect quickness of response.

Glad to see another person taking on the concertina making challenge.  

Dana

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Thank you Dana,  I’ve been passed the workshop of the late Harold Herrington so I have a really good head start if I were to build all these jigs and stuff myself.  Interestingly I have some letters and emails of his and he mentions you.

 

I appreciate you taking the time to really to my post.  

Cheers, Seth Hamon ~ Texas

 

Here is my first one as well as bellows #2 which are a huge improvement on the super stiff #1 due to switching from PVA to Hide glue.

 

 

D2BA15A3-BA35-46D2-B131-6D0FA2879459.jpeg

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Second bellows.

C7F1C6DE-0162-4DB3-AF73-94D3CD355225.jpeg

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There were some reed blanks among all the accordion reeds which look to be made by accordion makers with the single rivet hole and no venting on the bottom.  I’m going to compare

them to the Lachenal reeds.

9F5EBAC5-3CD4-4FFD-86FA-FA7D250C0388.jpeg

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The thing that’s I’m pondering is the width of the reed tongue slot that the reed freely swings in.  The smallest seem to be around 2mm, then move up to 2.2mm for the middle length ones and on to 2.5mm for the longer bass reeds.

 

Were these stamped or machined with various size slot widths or were they filed.  I guess I can try a set and go back and make changes if needed.  I was thinking of having all the reeds slots cut to 2mm but that would mean a lot of filing if the majority of them will need to be opened up

.

Cheers, Seth 

 

 

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1 hour ago, Seth said:

The thing that’s I’m pondering is the width of the reed tongue slot that the reed freely swings in.  The smallest seem to be around 2mm, then move up to 2.2mm for the middle length ones and on to 2.5mm for the longer bass reeds.

 

Were these stamped or machined with various size slot widths or were they filed.  I guess I can try a set and go back and make changes if needed.  I was thinking of having all the reeds slots cut to 2mm but that would mean a lot of filing if the majority of them will need to be opened up

.

Cheers, Seth 

 

 

 

It's normal for lower pitched reeds to be wider than higher ones. It helps with getting even volume and response across the pitch range. The actual dimensions and taper of the vent slot (if any) vary significantly depending on the maker, time period, and scale of the instrument. Most vintage reed frames were punched with a die set, with only a little filing required to clean up the vent. The dimensions produced by a punch will be pretty consistent from frame to frame.

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3 hours ago, Dana Johnson said:

Besides the fact that I’m pretty sure GB had not gone metric when these reeds were designed, ...

 

I know this is off-topic, but ...

 

The UK has still not "gone metric", thankfully. Some weights and measures were metricated, but we have all sorts of delicious exceptions and contradictions. Road distances are still measured in miles and yards, draught beer and cider is still sold in pints. In bottles it has to be metric, but what is 564ml if not a pint? Sheet building materials are still 8 by 4 feet (to line up with existing joist spacing), but the thickness is quoted as 13 or 19mm. And I'm sure most builders still refer to timber measuring 100mm by 50mm as "a bit of four by two".

 

LJ

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Wow Seth, are you the same maker who does the Swedish and Irish bagpipes? Must not have enough mischief to get into!

 

Ken (already admires your other work)

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4 hours ago, Ken_Coles said:

Wow Seth, are you the same maker who does the Swedish and Irish bagpipes? Must not have enough mischief to get into!

 

Ken (already admires your other work)

Same guy,

althouh mostly only Swedish Bagpipes and Scottish smallpipes as of the last 5 years or so, with the rare, Borderpipe, Binoou koz or Bechonett.

 

actually about to start on a Northumbrian Smallpipe 7 keys in F+20 soon.  I have plenty to do but when one area Ian slow I shift to another to keep my shop busy.

 

seth

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5 hours ago, alex_holden said:

The dimensions produced by a punch will be pretty consistent from frame to frame.

Makes sense why I’m getting exact measures on frames for Lachenal  #79,001 & 197,041.

 

Seth 

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All 17 frame sizes used on my 2 different 20 button Lachenal’s.  The only thing I’m not sure about is the taper of the reeds body.  It’s said to be 4 degrees traditionally but my milking jig from Herald Herrington cuts at a 5 degree angle so I’m listing them like that for water-jet cutting. I can always reduce the angle by filing but can’t go the other way.

 

the other thing is the screw size.  I’m going with 1-72  (approx 1.8mm) which is slightly larger than what is on the Lachenal which was 1.6mm.

 

Seth this could help someone else as I couldn’t find any information like this online when I was looking.

 

I do plan to measure the steel tongues next when there is time.

 

Seth

143836F8-D608-42FC-8465-846C75A8C2CF.png

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On 7/8/2019 at 10:48 PM, Seth said:

Here is my first one as well as bellows #2 which are a huge improvement on the super stiff #1 due to switching from PVA to Hide glue.

Well done, there is still time to run before it takes over your life...

 

Not sure I would accept the change of glue as a primary reason for the bellows being less stiff. It sometimes depends where you put it. And often when people say their bellows are stiff it is inefficient reeds to blame. 

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12 hours ago, Chris Ghent said:

Well done, there is still time to run before it takes over your life...

 

Not sure I would accept the change of glue as a primary reason for the bellows being less stiff. It sometimes depends where you put it. And often when people say their bellows are stiff it is inefficient reeds to blame. 

It’s the glue.  They were super stiff before I even took the set apart and after watching Alex Holdens photo tutorial I used cards only and switched to hide glue and the #2 bellows open up and close very well.

 

Probably is too late to run.  I was passed the workshop of a concertina maker who passed away several years ago, plus It gives me something to take the monotony away from 20 years of bagpipe making.

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Seth,

when you say “cards only” in the second set, what did you use in the first set?

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18 minutes ago, Chris Ghent said:

Seth,

when you say “cards only” in the second set, what did you use in the first set?

 

 

Folded from one solid sheet with the angles cut out on the bandsaw similar to how Tedrow shows on his website tutorial.

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Stiffness is a known side effect of folded strips, which were introduced when the industry was in financial strife as a way to cut costs  rather than a way to raise standards. I have used three different glues with no change in bellows stiffness. 

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31 minutes ago, Chris Ghent said:

Stiffness is a known side effect of folded strips

 

Striking me as highly probable...

 

32 minutes ago, Chris Ghent said:

which were introduced when the industry was in financial strife as a way to cut costs  rather than a way to raise standards.

 

Good to learn - I always mused about possible intentions to have the performance improved that way...

 

Best wishes - 🐺

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