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Chris Ghent

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  1. If it is cracked you may be able to confirm this by measuring its tune and then pull on the bellows really hard while watching the tuner. If it flattens and then doesn’t come back up then it will confirm Mike’s diagnosis.
  2. The bushings in the endplate should be glued in and unable to be pushed out by the button. If the bushings in the buttons are in good condition the buttons will not fall over so easily. Instructions for working on concertinas need to start with the following; 1. Find a calm frame of mind. 2. Be patient while you learn. 3. Do not take any setbacks personally, as this will get in the way of 1 and 2.
  3. If you want to measure the force needed put the action box on a digital kitchen scale (needs to be a larger one) and zero it. Push the button and read off the weight.
  4. I have found if you tell someone how to make a concertina they realise they don’t want to do it.
  5. The Morse is a very good instrument and would occasionally come up inside your budget.
  6. A good reason to use a fine thread for the machine screws is to increase the purchase the screw has in the captive nut. A coarse thread might only get a couple of turns in the nut.
  7. 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?
  8. 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.
  9. 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.
  10. 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.
  11. Not sure about the comparison between torsion and coil but phosphor bronze should last about 5 times as long as brass.
  12. Steve, about decibels; I knew that and perhaps expressed it clumsily but I said the level would halve, not the number because I didn’t want to introduce a concept such as a logarithmic scale into a simple discussion. And the level drop, say three inches from the concertina to the watch, so move the watch to six inches away, sound level halves, another foot it halves again so it is a quarter of what it was and your watch is about as far away as your ear.
  13. Loudness to the ear comes in two varieties. There is technical loudness and this conforms to square law. If you double the distance between your watch and the sound source the db level will halve. Your watch is very close and your ears at least twice as far away and perhaps as many as four times meaning it will halve again. The other variety of loudness is perceived loudness. One way this is created is by discord. We hear discord as louder (this is the principle accordions work on). Concertinas with loud higher partials which are naturally out of tune with lower partials will get in your ear and are unpleasant. This explains the experience of seanc above.
  14. If the bushed hole in the end was oval the button still should not be able to fall over. The only thing that will allow that is the pin at the bottom of the button being out of its hole at rest. To check this look along the buttons to see if that button is higher than the rest. If not, check if it is not a replacement button which is slightly shorter. If so bend the lever until the pin is in the hole and look for a better button. If the button is proud of the others it could be because the pad has compressed over time, or the hole in the lever for the rivet is elongated vertically (push down on the lever at the post and see if it moves downwards) or because the post is coming out of the actionboard. If the latter pull the post right out and put it back in with gel superglue and with a sliver of wood. In the old days you would have said with a shaving off a matchstick but who has one of them these days.
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