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Everything posted by jrintaha

  1. Solving for thickness, a = (f * l^2) / (sqrt(Y / rho) * 3.18), one gets to the unintuitive conclusion that as the desired frequency is lowered, while the reed length is kept constant, the thickness of the reed decreases. (As we all know, in real instruments the reeds get progressively thicker, not thinner, when we go down towards the deepest notes.) However, none of the instruments I own have reed tongues of uniform thickness (well, maybe the very highest pitched reeds might be); they're indeed always tapered so that the root of the tongue is much thinner than its tip. Assuming uniform thickness, a couple of notes (which I picked because I happened to have a Lachenal 20-key left reedpan at hand) and their respective thicknesses: G4 (the one above middle C): ~392 Hz, ~22mm tongue length, thickness would be ~0.0115mm C3 (the lowest sound on a C/G 20-key anglo): ~131 Hz, ~32mm tongue length, thickness would be ~0.0081mm A reed that thin would be impossible to file, I imagine, and extremely difficult to manufacture. (I also find it hard to fathom it could perform well in reality either, it's just so incredibly thin.) How would one factor in the relative thickness of the tip compared to the root? Some sort of empirical correction factor (or a table of correction factors for different operating points and their respective neighborhoods) applied to the formula? (Wish I had the time to further discuss this, but I have to go to sleep...) Cheers, Jori
  2. I've never laid my hands on a concertina that had such mesh screens, but I would hazard a guess that the grille cloth / mesh used for accordions should work for a concertina too. Take a look: http://cgmmusical.co.uk/CGM_Musical_Services/Grille_Bass_Linings.html (the shop itself is probably irrelevant because you live in the States, but no doubt someone in your general area is stocking similar materials). In the concertinas I have that have/had baffles, the baffles were made out of leather. The baffles cut off some of the higher frequencies of the sound, and depending on how tightly they're fitted, they may reduce the overall volume as well. Robert Gaskins' article on baffles: http://www.concertina.com/gaskins/baffles/index.htm The choice of adhesive will of course depend on what type of screen material you decide on. For cloth on wood, I'd use casein (milk glue), because it's easier to remove than PVA, and I use it for a lot of things anyway, but there's really nothing wrong with PVA either. For gluing metal or plastic, some kind of contact cement is probably required. Cheers, Jori
  3. That was used in the 70s, and maybe 80s. It was a disaster because the foam collapses and turns to dust after a couple of decades. Hmm, I'm almost completely sure I've seen foam-cushioned pallets in/for a Hohner box pretty recently (like a couple of months back). Must be a different material then, and apparently not a Hohner original, so it might not be so good after all. I take it you know your Hohners. Cheers, Jori
  4. Even 1mm thick 100% wool felt tears apart too easily in my opinion. Chamois (the wash leather kind) is pretty good for making damper rings, but the best leather I've come across is a type of sueded leather (listed as Persian suede facing leather here: http://cgmmusical.co.uk/CGM_Musical_Services/Felt_Leather_Pallets.html). It cuts very cleanly with a punch, does not tear, and eliminates sound effectively. (As a matter of fact, a concertina I have had leather dampers which were very old, at least 50 years old by my reckoning, so this is no new trick for repairmen.) As to whether it's better or worse than woven felt, I haven't measured, but at least it's a functional alternative. I also assume some sort of foamed plastic of sufficient density and thickness should work very well too. Some Hohner accordions use this type of foam for pallet dampers instead of felt. However, I couldn't find it in the latest Hohner spares list (http://www.hohner-cshop.eu/kataloge/HOHNER-Spareparts-ACCORDION-04-2012.pdf), so I don't know if they've discontinued it or just sell it as ready-made pallets. Also, it might be too thick for a concertina. I haven't pursued this alternative much farther, since the leather has worked fine for me. Cheers, Jori
  5. Hello, and sorry for the long wait. It's G-S Hypo Cement I've been using. To tell you the truth, I can't say anything about how it will hold after 10 years of constant playing, since lately I've barely had the time to squeeze the experiment box at all. The instructions that come with the tube advise against using it on a porous surface (such as leather), but the leather samper has held pretty nicely to the piece of silicon so far... Cheers, Jori
  6. Has anyone else ever tried using pieces of silicon tubing for making the grommets? I did this on a poor little Lachenal 20-key I use for notorious experiments in concertina repair. I think it was 3mm outside diameter, 2mm inside diameter tubing that I used. It fits pretty tight on the threaded ends of the key levers, so no glue is needed to attach them. Then I used a tiny drop heavy-grade plastic cement to attach the tube to the leather samper disc on top of the pad. Working on the keys is a bit faster this way, for instance if you need to replace the bushings, you can just pull off the piece of tubing along with the pad, and then get at the key. No need to pry off glued parts and re-glue them. Also, the silicon tube is very flexible and stays that way for much longer than a leather grommet I imagine. Besides looking ugly, I can't really think of any downside to using it - I think it does the job better than a leather grommet. I don't think it flakes off notorious substances or anything, since this is the stuff they use for medical equipment, and also for fuel transfer in RC airplanes. It's not that the leather grommets are too expensive to order or too difficult to make, but shouldn't one strive to make the best possible repairs for the instruments we have, even if it isn't traditional? Anyway, if someone knows of a specific reason not to use the tubing, I'd like to hear it before I apply the technique on something more valuable! Cheers, Jori
  7. I recently acquired a Wheatstone Duet, which obviously has the Wheatstone domed metal buttons - and they're really really uncomfortable compared to the buttons of the two 20-key Lachenal anglos I have. The other Lachenal, S/N 5088 has slightly larger, almost totally flat buttons than the other, S/N ~100000, which are slightly dome-shaped. But they both feel more comfortable than the Wheatstone, even after two weeks of not touching the Lachenals at all to get used to the Wheatstone. (Yes, the action and reed response are vastly superior in the Wheatstone, but I'd love to have the Lachenal buttons on it...) Cheers, Jori
  8. 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.
  9. For rust: I've used a small homemade brass brush (replaced the bristles of a small paint brush with brass wire from a big brass brush, then glued the whole thing back together with epoxy) and high-precision diamond files with good results. As for tuning: because accordions generally have several register switches, and usually just two sets of "regular octave" (8') reeds, the first set has to be tuned spot-on - because it will generally be used on its own or with the bassoon or piccolo reed set - and the second set is tuned slightly sharp. "Musette" accordions usually have the 3rd reed set tuned slightly less flat than the 2nd set is sharp. For a dry tone, you might want to try something like 5 cents sharp, maybe even less. I like to first tune the first set of reeds spot-on, then tune the 2nd reed set mostly by ear (playing both sets of reeds at once and listening to "beatings"). Usually you'll want to have a larger difference (measured in cents) in pitch for the lower notes than the high ones to achieve a progressively increasing "beating rate" across the tonal range of the instrument. http://talkingreeds.com/ goes into much more detail than I should in a forum post. Don't believe what they say about taking "stretching" into account though! An accordion is not a string instrument, and does not suffer from any noticeable inharmonicity like a piano or a guitar does. Cheers, Jori
  10. In order of proficiency: Electric guitar: proficient, can play almost anything I'm thrown at. (I cannot play classical acoustic guitar at all.) Electric bass: proficient, played technical thrash metal with my fingers where others struggle with a pick Keyboards: can play them somewhat, had private lessons in piano when I was between 9-11 years old, then gave up for a long time until a year or two back. Seems I haven't forgotten everything. Definitely can't play jazz yet. Piano accordion: I haven't really taken the time to learn any proper songs, but I jam along with just about anything. I've really spent much more time repairing accordions than playing them. Voice: I've a rather big vocal range I guess, "natural" bass voice starting from C#2, going well into the higher soprano notes with falsetto / "whistle" voice. I can hit notes accurately but I don't sound good yet Chromatic button accordion: I play it much less than the PA, because I only have a huge 81-button concert CBA (which really would deserve a better player) and it's too bothersome to take out since I rarely have the time to play more than 15-30 minutes at a time. (Three kids, need I say more...) Anglo concertina: I've only dabbled with playing these things, but I'm kind of getting the hang of it... somewhat. Looking for an EC or maybe even a duet now. As with accordions, I've spent like 10 times more time repairing than playing them. Ocarina: there isn't really much to learn on a 1 1/3 octave inline ocarina beyond being able to produce accurate notes, I maybe have to get a real sweet potato or double chamber ocarina some day. Wooden ocarinas sound absolutely marvelous, but are very limited in tonal range, and cannot be overblown to get higher notes like woodwinds which have reeds. I nearly bought a clarinet as well, and would like to take up a proper woodwind beside just the ocarina some day. I listen to and play almost every kind of music, but 70's progressive rock is the favorite that never phases out for me.
  11. I'd suggest just adjusting the height of the reed tongues, as it makes all the difference in the response of the reeds. It's much easier than most accordion servicemen would have you believe, and I'd say it's easy enough for just about anyone to do it. What you need practice for is doing it quickly enough for it to be financially viable. (My first block of accordion reeds I went through required long hours and several attempts before I got them right - my hourly pay for a fixed-price repair would have been next to nothing.) I have a used concert-size Excelsior chromatic button accordion with top quality hand made reeds and faultless workmanship throughout, the price tag for a new equivalent model being around $10000. I also have a junk Soviet box I got for almost nothing at a local auction. After re-gasketing the Soviet box and going through every reed one at a time, looking at the Excelsior reeds for guidance, setting them to the same height and alignment as in the Excelsior, there's not much difference at all in the reed response. It's all about the finishing touches! My suggestion: get a junk accordion off a local sale, try out the response of the reeds, note which reeds respond well and which don't (some are bound to respond well!), then try to bend the bad ones to the height of the good ones until you get the feel how to do it right. Then repeat it on your Stagi. Your Stagi has just a fraction of the reeds in your everyday accordion, so you can really take the time to get everything just perfect. Or you could phone your nearest accordion service shop and ask how much they'd charge for doing it. Remember, compared to just about any accordion, there are (fortunately!) so very few reeds in a concertina! Cheers, Jori
  12. Now I'm tempted to. I have a particularly roughed up 20-key Lachenal on the desk, and rather than repairing the fretwork with wood, I wonder if I could coat the damaged fretwork with thin celluloid, then remove some wood from the fretwork piece's bottom side (the part which connects to the action board) to make up for the keys "sinking" due to increased thickness of the fretwork. It's not like it would be a big loss if it didn't turn out well.
  13. Celluloid is widely available, since most accordions are plated with (usually black) celluloid, and many accordion repair shops stock it. They don't sell it for cheap exactly, but then again you won't need much for a concertina's fretwork. The reason for using celluloid (I believe) is that it's relatively easy to repair, especially black celluloid. Celluloid dissolves very rapidly in acetone, and becomes malleable when subjected to a relatively low heat - you can bend it slowly by applying hot cloths for instance. Also, it's not that flammable (unless dissolved in acetone). You can set it aflame by holding a celluloid sheet to a cigarette lighter flame for several seconds, but that's hardly something you could do by accident. [Edited to correct typos.]
  14. Thanks for the advice, everyone. So I take it that this http://www.ebay.co.uk/itm/110837082055, for instance, isn't quite worth the £300 asked? Brass reeds, probably in very bad condition, 4 fold bellows. Then again, this http://www.ebay.co.uk/itm/Lachenal-48-Key-English-Concertina-Original-Case-No-54190-/280841299282 is going at £200 and there's a week of bidding time left. Hard to image it wouldn't go over £300. This one http://www.ebay.co.uk/itm/antique-concertina-/260971284238 might be worth watching? (Someone's gone through the trouble of adding new baffles by the looks of it, so maybe it's been taken care of properly.) Cheers, Jori
  15. Well, it seems I'm getting deep enough in this concertina thing, that the two 20-key Lachenal anglos I have don't quite cut it any longer. Both were purchased in need of restoration, one is almost in complete playing order now, the other needs to be tuned to concert pitch and some bellows work when I have the time. So I'm asking what would be a reasonable price to pay for a Lachenal 30-key anglo or 48-key English? (The duet, due to its peculiar button layout, doesn't seem that enticing to me - I feel I wouldn't have the time to learn it even remotely properly.) I guess I'd be more inclined to buy one in need of restoration, because I love working on these boxes, and am very interested in their inner workings. I don't think I'll be getting a Wheatstone worth several grand quite yet - the Department of Time and Money said I'll get one only after she gets her industrial sewing station and made-to-shape earplugs. Also, what would be a fair price to ask for a fully restored (cleaned, woodwork + bellows repaired, pads replaced, levers bushed, reeds tuned etc.) 20-key Lachenal? I've already got a queue of people who want to borrow my other box when I get around to tuning it properly - seems that little box garnered quite a bit of attention when I showed it to a couple of friends. (Might be the only ones of their kind in this corner of the Earth.) One wanted to buy it right away, but as I couldn't say a fair price, I told him he could borrow it when I get it in working order. Thanks in advance, Jori
  16. Lucy, are only wheat and rice starch pastes viable? The mix sounds very interesting, and I take it it's a bit more reversible than PVA. I've got wheat, corn and potato starch in the cupboard, but since I've got coeliac disease, using wheat starch is a bit risky, since if I get the tiniest bit in my stomach (contaminating food by wheat carried under my fingernails for instance), it's gonna be a not-so-cheerful day at the loo, and the grocery store nearby doesn't have any rice starch. Cheers, Jori
  17. I've been using a casein-based glue (it's called "maitoliima" here, which translates verbatim to "milk glue") for bellows repair and making pads, for both accordions and concertinas. So far so good, but I don't know if it will as long as hide glue or PVA. Anyway, they even used it for building aeroplanes, which apparently caused some crashes when flying in the humid (and hot) weather conditions in Asia (see http://en.wikipedia.org/wiki/De_Havilland_Mosquito#Construction). But I reckon unless you're planning on flying to Asia with your concertina, it should be OK. The milk glue does not need any heating, so no need to make a mess in the kitchen. It does smell like rotten milk if you give the tube (or mixing pot if you're mixing from powder) a good whiff up close, but the smell goes away when it dries, and the smell really does not carry further than 30cm or so. So there shouldn't be any complaints. Oh, and as a bonus, the glue is machine-wash-proof up to 40 degrees Celsius, so uh, if you ever decide to give your concertina a spin in the washing machine, milk glue is highly recommended. Cheers, Jori
  18. Since Gloy Gum has disappeared, the only other alternative that I know of is the gum arabic crystals. You can get them from the wicca sites, just dont put a hex on the concertina, although the are already hex-agonal, or at least most are. (sorry) Dave You can also obtain Gum Arabic from artists' suppliers, e.g. Winsor and Newton: http://www.winsornewton.com/products/oils-solvents-mediums-varnishes/water-colour-mediums/gum-arabic/ Do you know how well Gum Arabic holds to metal? Does it "string" easily? Shellac strings a bit, which is somewhat annoying when trying to finish a big block of accordion reeds fast. Might try buying a bag of gum pearls, make my own mix and see how it feels. I'm guessing the watercolor thinner solutions are too thin to be used as glue, and you'd have to let them dry a bit first. Also I'm a bit concerned about the shelf life of such solutions, as I think they're mixed with glycerine, and at least shellac goes bad pretty quickly after it's mixed with alcohol. Cheers, Jori PS. Do not ever ever ever try using burnt shellac as a valve glue, unless you've somehow discovered a magical leather that will never have to be replaced again. I once tested burning shellac in a teaspoon (I think it was one of Pietro Deiro's accordion handbooks or some such old manuscript that suggested it) to see how well it would stick to metal. Well, after scraping it first with my fingernails and then with a knife, and after 20 or so rounds in the washing machine, the spoon is still coated with burnt shellac. Holds just a bit too well!
  19. I'm not sure if the original poster is still in need of an answer, but after experimenting with a dozen different adhesives I've ended up using shellac for gluing accordion valves (that is, leather to metal). I'd recommend against using shellac varnish in a bottle, because its shelf life is rather short, and if it's too old, it will not glue well. I use raw shellac flakes which I dissolve in ethanol. (Bleached and coloured shellac flakes have been soaked in acetone to dissolve some of the colours, and the treatment probably affects its gluing properties, so I wouldn't use them just to be on the safe side.) When re-valving accordions, one easily goes through hundreds of valves depending on the size of the box, so it's essential that I can streamline as much of the operation as possible, and this is where shellac comes in. Just open my jar of prepared shellac (I leave it a bit softer than honey), dip a brush or toothpick in the shellac, spread a bit on a reed plate, rinse & repeat. After all reed plates have shellac on them, press valves on them. It dries so slowly you can complete a whole block of reeds in one go, and you can adjust the alignment of the leathers to be just perfect, whereas with a lot of contact cements, metal glues and super glues, you get one go at getting it right, and then it's already glued tight. The downside with raw shellac flakes is that they're very expensive to buy in sensible quantities. http://www.shellacshack.com/ is a US supplier, but unless you're running an antique restoration shop, their 1 lb bags will last a very long time. And I don't think their prices are that good, because I've been buying shellac flakes at roughly 25€ a kilogram (roughly 33 USD per 2.2 lb) in Finland, the land of everything is expensive. Cheers, Jori
  20. Possibly a weak or mal-functioning spring, (or springs)? Check the condition and strength of the spring related to the intruding/unwanted secondary note and if necessary replace it with a new spring. Have you tried shining a light through the reedpan from the other side in a dark room? I'm still waiting for my first concertina to arrive in the mail, so I'm not 100% sure if this is possible to do easily in a concertina, but I've restored several old (up to ~80 years old) accordions, and that's a very handy trick in finding the leaking pads. Might be a misaligned (due to weakening string, warping of the wood etc.) pad?
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