New makers… a suggestion quick release

[seanc]

22 hours ago, Steve Schulteis said:

 

I used to hold this view as well, but while Phillips solves the problem of keeping the driver aligned with the screw head, it was designed to cam out as a means of limiting torque, marring the head in the process. I now prefer star or hex drive, the latter having an advantage for concertinas in that it's easy to tuck an Allen wrench securely in the corner of a concertina case, and it's more likely that someone else has the correct wrench handy in the event that it gets lost.

 

 

 

I've spent some time considering alternative action systems, and even done some prototyping. At this point I'm satisfied that the standard system is pretty hard to beat. Not that it's perfect, but it's got a good balance in its compromises. It's still fun to experiment though, and I'd be curious to see a drawing of your design to see if I'm picturing it correctly. A bit off topic here, so maybe PM me or start a new thread.

 

Is spring lifetime an issue? Torsion springs are capable of surviving millions of cycles if designed correctly.

 

I have had a few springs just die. Maybe it’s age, or use over time. The ones in the ( presumably orig) were brass, or bronze. Many appear to be oxidized. I soirced some stainless springs and many were not right size wise to fit. So, I started making my own with phosphor bronze. 
 

what I can say, is that there is a huge difference between the new and old springs. The new springs are substantially stiffer. In a good way. This makes the action noticeably faster. And the notes on the release a quicker to stop. And the end of the note on release is more defined. The height of the new spring buttons are also higher, and in my estimation more uniform with the other new buttons. 
 

what this means, to me, is that the new springs are faster, and taller. The old springs by contrast, feel mushy and slow. I am finding the lack of consistency to be an issue. The newer springs lend themselves to allowing for playing faster and more cleanly.

 

[Steve Schulteis]

Obviously springs do wear out. My question is if torsion springs wear out at an unacceptable rate, particularly compared to coil springs made from the same material.

[alex_holden]

3 hours ago, seanc said:

what I can say, is that there is a huge difference between the new and old springs. The new springs are substantially stiffer. In a good way. This makes the action noticeably faster. And the notes on the release a quicker to stop. And the end of the note on release is more defined. The height of the new spring buttons are also higher, and in my estimation more uniform with the other new buttons. 

 

what this means, to me, is that the new springs are faster, and taller. The old springs by contrast, feel mushy and slow. I am finding the lack of consistency to be an issue. The newer springs lend themselves to allowing for playing faster and more cleanly.

 

It sounds like you're making the new springs considerably stiffer than the old ones were. That's fine if it's what you prefer, but many players value a 'light action', i.e. buttons that don't take a lot of force to press. It is important for all the buttons on a particular instrument to be fairly consistent.

[Chris Ghent]

6 hours ago, Steve Schulteis said:

Obviously springs do wear out. My question is if torsion springs wear out at an unacceptable rate, particularly compared to coil springs made from the same material.

Not sure about the comparison between torsion and coil but phosphor bronze should last about 5 times as long as brass.

[seanc]

5 hours ago, alex_holden said:

 

It sounds like you're making the new springs considerably stiffer than the old ones were. That's fine if it's what you prefer, but many players value a 'light action', i.e. buttons that don't take a lot of force to press. It is important for all the buttons on a particular instrument to be fairly consistent.

Unknown… doing 2 wraps with 22swg phosphor bronze. I don’t have a way of making an accurate reading of spring vs sping.

 

maybe I have played guitar so long that I prefer stiffer. But I certainly appreciate them being faster.  

[Chris Ghent]

34 minutes ago, seanc said:

Unknown… doing 2 wraps with 22swg phosphor bronze. I don’t have a way of making an accurate reading of spring vs sping.

 

maybe I have played guitar so long that I prefer stiffer. But I certainly appreciate them being faster.  

If you do three turns it will be a little easier to adjust to a good weight. To adjust the spring tension put the end on a cooking scales calibrated in grams and zero the tare for the weight of the end. The scale will then read out the spring tension. This idea from David Hornett. 

[seanc]

9 minutes ago, Chris Ghent said:

If you do three turns it will be a little easier to adjust to a good weight. To adjust the spring tension put the end on a cooking scales calibrated in grams and zero the tare for the weight of the end. The scale will then read out the spring tension. This idea from David Hornett. 

Without getting too far down a physics rabbit hole…

 

is spring tension always directly related to speed?

 

is that a function of metal composition or gauge?

 

or (making crap up here) is a 4lb spring always going to respond the same way regardless of material or gauge? And the only real factor here is longevity?

[Chris Ghent]

Regarding the idea of a simpler way to take the end off; when I was contemplating this about twenty years ago I favoured a hinge down one side and a clasp of some sort on the opposite side. I never did do it, I realised I was coping with taking the end off and no-one was ever going to do it more times than me. If you are dealing with anything other than a leak you needn’t put all of the screws back in to test it, half will do. Or just hold the end on. 
 

I often thought about a story I heard about Model A Fords, about the design of the carburettor; how Henry Ford was offered a design by Zenith which worked extremely well  but Ford was put off by the 9 screws that held the lower part of the carb to the upper. Zenith came back and said, its OK, we’ve got it down to three. Ford said, make it one. They did and it worked extremely well, I took mine apart a couple of times beside the road and you could have it apart in seconds.  

I considered one screw for concertinas but it would be big, and heavy, and the structure would need to change to spread the load from the middle to the sides evenly. 
 

There is not much about the traditional concertina design that is terrible, if I was starting now knowing what I know now I would put time into a different way of attaching the reed frames to the pan. See Dana Johnson’s method for a good example. The traditional way is fine for low efficiency reeds such as Lachenal’s. Jamming a high efficiency reed into a wooden slot which is always adjusting its size in a unpredictable way is silly. 
 

Oh, and I vote for slot heads. 

[Chris Ghent]

3 minutes ago, seanc said:

Without getting too far down a physics rabbit hole…

 

is spring tension always directly related to speed?

 

is that a function of metal composition or gauge?

 

or (making crap up here) is a 4lb spring always going to respond the same way regardless of material or gauge? And the only real factor here is longevity?

Speed of what? The overall speed of the concertina has limitations associated with reed clearance and chamber size. The only thing that changes with heavy spring weight is the button may rebound a little quicker and also may cut the note off more abruptly on push notes (draw notes are sucked shut so will cut anyway). 
 

Heavy spring tension may lift the posts out of the action board and cause pad recession, both of which will result in buttons lifting to high and perhaps becoming unseated. 
 

In general I find heavy spring tension makes an instrument feel slow and harder to play, but I know other opinions are held. 
 

Pretty much any springy and durable metal can be used for springs; brass has been most common but steel has been used. Some modern makers are using SS. Is anyone using brass? I know some use phosphor bronze. 
 

For a long lever I think .xlb is .xlb (not going to contemplate 4lb) no matter the material. There is an effect called rising spring rate which affects short levers. The rate of rise might be different with other materials; this is beyond my experience. Also you would not want to be anywhere near the plastic point for the material. 
 

There is no need to reinvent this, if you don’t want rust don’t use non stainless steel. Brass will work well and is easier to work than SS  but it will break sooner, so use phosphor bronze. 
 

In an emergency don’t use a safety pin, pinch a spring from a button you don’t use and tape over the pad hole of the lever without a spring from underneath until you can get one. 

[wunks]

12 hours ago, Chris Ghent said:

 

Oh, and I vote for slot heads. 

Well how 'bout a "captured" or "housed" slot head?  I can visualize such a thing; just a modification of a square drive.  

[alex_holden]

41 minutes ago, wunks said:

Well how 'bout a "captured" or "housed" slot head?  I can visualize such a thing; just a modification of a square drive.  

I’ve pondered doing that occasionally, but I haven’t come up with a great way to cut the slot in the small size needed (please don’t suggest milling it with a 0.6mm dia end mill). A possibility might be sawing the slot in the normal way and then gluing/soldering a short length of thin wall tube to the outside, then profiling and polishing the head afterwards. It would likely end up a slightly larger overall diameter though. 

[wunks]

McMaster-Carr lists black oxide socket head (Allen) bolts with the right head profile.  Fine thread is available but I don't know about sizing.  Perhaps the hex socket could be turned into a slot with a couple of epoxied shoulder pieces.

[SIMON GABRIELOW]

It sounds like a sort of Frankenstein monster is being gradually evolved, in this 'thread'... With bolts on it, and who knows what else! 😁😁😁😁And all made with my own hands, my own hands! As the film goes!😄😄😄

Edited February 25, 2023 by SIMON GABRIELOW

[Stephen Chambers]

The simplest method ever was probably that used in Wheatstone's first concertina (my avatar, and the most precious instrument in my research collection of early concertinas and related instruments) and a handful more of the very first, "open-pallet model" concertinas that were ever made.

 

 

The idea, like much-else in the design and choice of materials, was borrowed from Cyrill Demian's (1829 Patent) accordions, and the action-board is a sliding fit into the end-frames (much like the lid of a wooden pencil case) secured by two screws:

 

 

But subsequent open-pallet model Wheatstone concertinas had six end-bolts instead, which must have been considered a design improvement...

[Richard Mellish]

With that sliding arrangement, making a good seal between the tops of the reed chambers and the action board must surely depend on very fine tolerancing. How well does it work still work after all those years? Tightening screws around the edge seems a more promising way of making the seal, and particularly of compensating for slight movements of the parts.

[Anglo-Irishman]

On 2/22/2023 at 3:14 PM, RAc said:

Also, if I did enjoy looking at slotted heades, something inside me would argue that they would look even better if the slots were perfectly aligned or had some other geometric aesthetic to them such as radial alignment. It wouldn't be a good idea to try that, though.

Just as an aside: this reminds me of the banjo player who maintained that is banjo was tuned correctly when all the tuner knobs faced in the same direction ... Not a good idea, either!

I think a certain randomness can be quite aesthetic when it results from necessities other than the aesthetic.

Cheers,

John

[JimLucas]

On 2/21/2023 at 12:44 AM, seanc said:

if there is a way that would be cost effective. I would suggest/ ask/ beg. That somehow some sort of quick release, maybe latch,   Boots with cotter pin, or even hex head nuts that stops and can not be over tightened. 

 

just something that is easy and not intimidating for a potential player to open up and fiddle and also a way to provide consistent and idiot proof to seal back up.

Idiot proof?  Why would you want to make it easier for idiots to open a concertina?

 

Meanwhile, a complaint I have with some "modern" concertinas is that they use modern-standard machine screws, where the threads have a much shallower pitch than those on the "old-fashioned" instruments.  That means many more turns of each screw when opening and closing the instrument.

 

Okay, nobody seems to make screws of any sort these days with such steep pitch.  But anyone with a screw-making machine could do so.  Decades ago, Steve Dickinson made some for me, but he can no longer take the time to be a parts-maker for others.  I actually had thoughts of asking a Russian friend if he could do it -- I could maybe pay for a thousand... at a time, if I could sell the entire first batch, -- but since the invasion of Ukraine, I'm unwilling to contact him, for fear that contact from an American would put him in danger.

 

As for the type of head, I still find slot-head screwdrivers of the right size far easier to obtain than any of the alternatives.  And I always keep a couple with my instruments, noting that not all "slots" are the same size.

[Chris Ghent]

On 2/27/2023 at 10:55 PM, Stephen Chambers said:

The simplest method ever was probably that used in Wheatstone's first concertina (my avatar, and the most precious instrument in my research collection of early concertinas and related instruments) and a handful more of the very first, "open-pallet model" concertinas that were ever made.

 

 

The idea, like much-else in the design and choice of materials, was borrowed from Cyrill Demian's (1829 Patent) accordions, and the action-board is a sliding fit into the end-frames (much like the lid of a wooden pencil case) secured by two screws:

 

 

But subsequent open-pallet model Wheatstone concertinas had six end-bolts instead, which must have been considered a design improvement...

Stephen, thanks for this glimpse into the mechanics of the first concertina! When you handed it to me in 2012 it was a great moment I will never forget. Especially as you had just shown me Demian’s instrument. 
 

It looks as if every reed is leaded, well, those that can be seen. Is this a preferred tuning method in the concertina?