Marien Posted July 18, 2007 Share Posted July 18, 2007 (edited) I have seen concertina's with metal buttons, glass, bone, plastic, wood with a metal cap or a bone or ivory top. To me, for its low weight, the wooden button with the metal cap is the most attrective one of these. But I heard that they (rarely) can brake where the lever goes through. What I have never seen is buttons made out of carbon with a metal cap. Like for badminton rackets, it would combine low weight with strength, and carbon seems to be more solid than wood. Could that be the material for our future concertina button? Or is there a concertina maker who already uses it? Edited July 18, 2007 by marien Link to comment Share on other sites More sharing options...
Chris Ghent Posted July 18, 2007 Share Posted July 18, 2007 I have seen concertina's with metal buttons, glass, bone, plastic, wood with a metal cap or a bone or ivory top. To me, for its low weight, the wooden button with the metal cap is the most attrective one of these. But I heard that they (rarely) can brake where the lever goes through. What I have never seen is buttons made out of carbon with a metal cap. Like for badminton rackets, it would combine low weight with strength, and carbon seems to be more solid than wood. Could that be the material for our future concertina button? Or is there a concertina maker who already uses it? I have looked at carbon fibre for other parts in the concertina, and while it is light and strong and is used in applications such as guitars because it has good tone qualities it suffers from one drawback. It is very hard to machine. If you can't turn it easily then you are in trouble for buttons. It might be possible to mould it but this would mean an expensive foray into a whole new manufacturing area. There is a saying in the engineering field, "light, strong, cheap... choose two..." Seeing it is a part no-one is going to see it really doesn't matter what it is as long as it passes the strength test. Almost everything does, including wood, most breakages of wood only happen after many years of playing. However the best woods would probably also be the heaviest woods. If weight is important to you, plastic (delrin/acetal) which is cheap and easy to turn, would be the lightest, especially if paired with a titanium cap. I think Colin Dipper uses a Delrin lower and brass upper. Making the caps is also a tricky thing. They can be machined but would have thicker walls than the vintage ones, adding to weight. In order to make drawn caps like on a Wheatstone you need to make a series of jigs, ie. serious toolmaking. This is one reason most modern makers use a single material, a metal or plastic, to create buttons. The other is, why make a two part item when you can make a one part item, saving on assembly time. It would be almost equally as quick to make the whole button as to make the lower part only for a composite button. This makes the achievements of those who make composite buttons all the more remarkable. Chris Link to comment Share on other sites More sharing options...
paperpunchr Posted July 18, 2007 Share Posted July 18, 2007 (edited) "Carbon" is generally a carbon fiber fabric saturated with a bonding plastic...it's really a carbon-fiber-reinforced plastic, sort of similar to fiberglass car body parts, not solid carbon...it's advantages of lightness and tensile/flexural strength aren't really critical in a compact application like concertina buttons...it's good for car chassis and body parts and aircraft frames where the strength of the carbon fiber lets longer structural parts be really light for a given amount of strength, compared to even aluminum or titanium. ...several 'tina makers are currently using an easily machinable plastic called Delrin that is light and strong and almost indestructable in this kind of use, compared to traditional materials, and more commonly available than carbon fiber plastics. For the forseeable future carbon has no real advantages over Delrin or the other moldable/machinable plastics now in use for this kind of part that I can see. You can sort-of machine carbon fiber reinforced materials, but it tends to leave raggedy fiber ends and a potentially harmful dust something like fiberglass but electrically conductive...there was worry in early uses about carbon fiber fragments causing problems if they got into electronic components, not to mention lungs... Retired chemical engineer with lots of hobbies and odd interests, me... Ah, Chris, you beat me to the punch! :-) Edited July 18, 2007 by paperpunchr Link to comment Share on other sites More sharing options...
ragtimer Posted July 19, 2007 Share Posted July 19, 2007 ...several 'tina makers are currently using an easily machinable plastic called Delrin that is light and strong and almost indestructable in this kind of use, compared to traditional materials, and more commonly available than carbon fiber plastics. For the forseeable future carbon has no real advantages over Delrin or the other moldable/machinable plastics now in use for this kind of part that I can see. Wim Wakker uses hollow metal buttons with Delrin cores in his latest models. Another advantage of Delrin, if it's like Nylon or Teflon, is that it's self-lubricating when in contact with the metal lever end, and doeesn't wear itself or the lever out. Cheap 'tinas have the metal shafts of the button working directly on the action lever end, which wears quickly, leading to low buttons and short travel. Fine instruments have a felt bushing inside the button shaft to protect the lever end (and keep things quiet), but after hours of playing hte felt gets pounded down and needs replacing. Delrin might solve these problems. I know that Delrin has been used as jacks and plectra in harpsichord building for 40 years now, so it's earned its musical pedigree Link to comment Share on other sites More sharing options...
JimLucas Posted July 19, 2007 Share Posted July 19, 2007 The difference in weight between a set of solid brass buttons and a set of Delrin buttons... approximately what is that as a percentage of the weight of an entire instrument? How significant is the effect on playing? Link to comment Share on other sites More sharing options...
Robin Madge Posted July 19, 2007 Share Posted July 19, 2007 I've had several breakages on the plastic cored, metal capped buttons on my 1960's 40 button C/G Wheatstone. They always go at the lever hole, and as the bushing is quite tight in the end I have been able to play on for some time, wondering why the button is depressing further. Robin Madge Link to comment Share on other sites More sharing options...
Richard Morse Posted July 19, 2007 Share Posted July 19, 2007 The difference in weight between a set of solid brass buttons and a set of Delrin buttons... approximately what is that as a percentage of the weight of an entire instrument?Hmmm.... Delrin weights 0.054#/cu.in. and brass weighs 0.309#/cu.in..... times the volume of a 1/4" cylinder just under an inch long times 30 buttons totals something like 134 grams for Delrin and 771 grams for brass. Considering the average 30 button anglo to be about 1300 grams means that.... woooooo Delrin buttons would be 10% of the weight. Brass buttons would be 59% of the weight. Brass buttons with stems would be 44% of the weight. Obviously this "standard" needs some adjusting. Looking at concertina weights shows the metal buttoned ones (Jeffries, Connor) to be about 1400 grams and Delrin buttoned ones (Morse) to be about 960 grams. 579 grams for stemmed metal buttons less 134 for Delrin = 444 grams. Concertina weights 1400 - 960 = 440 grams. Wooooo..... Pretty amazing check! Seems like the overwhelming difference in the weight of the boxes is due to the weigh of the buttons. Still, that needs to be tempered by realizing that Jeffries has a meatier reedpan and brass reed shoes and metal ends while the Morses have aluminum reedplates (though there is a LOT more plate than shoes), wood ends and cherry frame (considerably lighter than veneered maple). I also note that most metal buttons tend to be just caps, which is probably why the concertina weight differences isn't greater. The only boxes I remembering having solid buttons are the Holmwoods (Hamish Bayne) which are very heavy boxes, though they have 56 keys (of thinner diameter and they are drilled out beneath the ends to reduce the solid buttons weight somewhat). How significant is the effect on playing?The only solid brass button concertinas I've played are the Holmwoods. I found the action pronouncedly different though I really can't say how much of that is due to button weight/mass as I'm not much of an English player. His buttons are very domed and aggressively sprung which made for tiring playing (even though supported on my thigh). I've heard from several people that his boxes have noticeable mass-response differences with some people really liking it and others hating it. I would think that this would make the box a slower player (right.... like Simon Thoumire is a slow player?) or cause action maintenance issues (stronger springs can pull the pivot posts out, more rivet wear, etc. though I haven't seen any problems like this come through our shop). -- Rich -- Link to comment Share on other sites More sharing options...
Marien Posted July 19, 2007 Author Share Posted July 19, 2007 How significant is the effect on playing? I didn't think about the total weight of the concertina, more about the mass of the action and the ease of playing ornamentation and in fast tunes. There may be a weight balance between pad and button, but the mass of the whole action may have an effect. When it is heavy it needs more power to press the button fast, at least, I was asking myself whether this would make a difference or would you say that it's insignificant? Link to comment Share on other sites More sharing options...
Marien Posted July 19, 2007 Author Share Posted July 19, 2007 I've had several breakages on the plastic cored, metal capped buttons on my 1960's 40 button C/G Wheatstone. They always go at the lever hole, and as the bushing is quite tight in the end I have been able to play on for some time, wondering why the button is depressing further. Robin Madge If the plastic is from 1960, it may be of inferior quality. Delrin sounds to be very suitable, seems to be used for prothesis as well. Link to comment Share on other sites More sharing options...
JimLucas Posted July 19, 2007 Share Posted July 19, 2007 The difference in weight between a set of solid brass buttons and a set of Delrin buttons... approximately what is that as a percentage of the weight of an entire instrument?Delrin buttons would be 10% of the weight.Brass buttons would be 59% of the weight. Brass buttons with stems would be 44% of the weight. Much more than I imagined. I'm glad I asked. Link to comment Share on other sites More sharing options...
Richard Morse Posted July 19, 2007 Share Posted July 19, 2007 The difference in weight between a set of solid brass buttons and a set of Delrin buttons... approximately what is that as a percentage of the weight of an entire instrument?Delrin buttons would be 10% of the weight.Brass buttons would be 59% of the weight. Brass buttons with stems would be 44% of the weight. Much more than I imagined.I'm glad I asked.Now the reason why smaller diameter buttons for the English starts to make more sense. Can you imagine how much a box would weigh with 48 (rather than just 30) 1/4" diameter brass buttons? Not to mention that many more reeds/shoes.... -- Rich -- Link to comment Share on other sites More sharing options...
Dana Johnson Posted July 20, 2007 Share Posted July 20, 2007 One more thing about button materials aside from the weight ( and Rich aren't most Metal buttoned Jeffries solid NS? also pretty heavy stuff, which for most of the metal one's I've seen had thin drawn caps over wood or plastic) is the friction of the button against the bushing. Delrin tends to polish in when played and get slicker. Nickel silver or nickel plated buttons also seem to stay smooth as long as they are played, as do bone buttons. I have noticed many brass buttoned (capped or otherwise ) concertinas tend to build up a sticky oxide layer that doesn't want to polish down as well and gradually increases the friction over the years. Playing is usually sufficient to keep it more or less yellow, but not to smooth it. A different alloy might help, but good deep drawing alloys may not provide good friction properties. Nickel plate seems to do the trick, but doesn't have the same look. Brass also has an annoying tendendcy to build up green verdegris in combination with finger oils, acids and the like. This rubs off in the bushings making them more siticky. Naval brass might resist this, but I don't know how well it can be drawn into caps. Dana Link to comment Share on other sites More sharing options...
OLDNICKILBY Posted July 20, 2007 Share Posted July 20, 2007 Based on a 56 key English the following weights apply:- Lachenal Edeophone 1.350Kg Holmwood Rosewood 1.795 Kg Wheatstone Metal ended 1.845 Kg Delrin buttons would weigh in at 22g Brass CZ 101 nickel plated 170 g both for a set of 56 Which looks as if the brass would add a mere 150g to the overall weight of the Tina I guess that this sort of lays the myth that Holmwoods are heavy, to rest! Link to comment Share on other sites More sharing options...
Richard Morse Posted July 20, 2007 Share Posted July 20, 2007 I guess that this sort of lays the myth that Holmwoods are heavy, to rest!Depends upon one's perspective.... The Holmwood is almost twice as heavy as a Morse. The Holmwood is also lighter than most accordions.... -- Rich -- Link to comment Share on other sites More sharing options...
OLDNICKILBY Posted July 20, 2007 Share Posted July 20, 2007 What I was saying, quite politely, was that you seem to have the calculation a bit wrong. Delrin would weigh in at 22g whilst brass would be 170g pe set of 56 Regards Old Nic Link to comment Share on other sites More sharing options...
Leo Posted July 21, 2007 Share Posted July 21, 2007 Way back in 2004 there was a small discussion about using imitation ivory: http://www.concertina.net/forums/index.php...95&hl=tagua A name for it is Tagua Nut or Vegetable Ivory. The only thread that mentions it doesn't go into the subject very deep. A neighbor and good friend makes pens for a hobby and uses it occasionally for his projects and it's almost impossible to distinguish it from bone or real ivory, and looks nice. Would it make a suitable button material? Thanks Leo Link to comment Share on other sites More sharing options...
Pete Dunk Posted August 7, 2007 Share Posted August 7, 2007 (edited) ...several 'tina makers are currently using an easily machinable plastic called Delrin that is light and strong and almost indestructable in this kind of use, compared to traditional materials, and more commonly available than carbon fiber plastics. For the forseeable future carbon has no real advantages over Delrin or the other moldable/machinable plastics now in use for this kind of part that I can see. Retired chemical engineer with lots of hobbies and odd interests, me... Twenty odd years ago I used 1/8th inch (3mm) black and white Delrin rods as the bridge pole pieces on the hammered dulcimers I made. They are still there and if you take one out and look at it you will find that the strings haven't even managed to mark it. Unless you are obsessed with using only traditional materials I can't think of any reason why you wouldn't use Delrin to make concertina buttons. I feel pretty sure the innovative Charles Wheatstone would have done so if it had been around in his day. (edited to add a closeup of the bridge) Edited August 7, 2007 by tallship Link to comment Share on other sites More sharing options...
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