 The Clarinet BBoard
|
Author: steve
Date: 2002-01-14 13:51
There have been a number of threads recently about "crack-proof" clarinets (plastic, ABS, Greenline). There has been a thread about the fact that the physics of clarinet sound production suggests that, since it is the vibrating air column that produces the sound, the material of the tube is irrelevant (execept to hold all the key and ring hardware). There are frequent threads about cracking wooden clarinets. I am curious: Does anyone know which of the synthetic/plastic clarinets are molded or extruded and which are cast as a block and machined to produce particular bore tapers. I am a beginning/intermediate player still using a glossy-finish Vito -- it sure looks extruded, not machined.
|
|
Reply To Message
|
|
Author: Don Berger
Date: 2002-01-14 14:35
Steve - For several months, I have been searching patent art for machinery and techniques for refacing/facing mouthpieces due to interest expressed by Dave Spiegelthal, Manfredo Cavallini of Italy [who refaced a glass for me, good!] and my own curiosity as an engineer/clist. I really havent found much so far, prob such patents may be classified in a variety of US and Intl. patent classes and not cross-referenced into US Class 84 and Intl. G10B, Music etc..Techniques may be non-patented trade secrets! The older patent to Jack Linton on the plastic-sleeve insert for their oboes [etc?] may be of interest to you and viewable on the USPTO and Delphion patent sites. I'll post the pat # when I find my copy, or re-search it out. Also, I'll expand my search to the clarinet body, hopefully to turn up Buffet's technique re: the Greenline. Thanx for posting an interesting question. Don
|
|
Reply To Message
|
|
Author: Peter
Date: 2002-01-14 15:08
I would venture to say that molded and cast would require less machining than extruded instruments.
Extruding would produce a straight tube, and all eventually differing diameters in the bore would have to be machined, whereas with modern investment casting and injection molding they could get tolerances almost perfect in the molding casting process.
|
|
Reply To Message
|
|
Author: beejay
Date: 2002-01-14 15:31
The Greenline is machined from billets of the material, in the same way as a wooden cl. However, the material is much harder, and some of the machine tools had to be built specially.
|
|
Reply To Message
|
|
Author: ron b
Date: 2002-01-14 17:24
My limited understanding is that extruding works well for producing pipe and wire. Clarinet bodies? Maybe.
'Plastic' Bundys and Vitos I've worked on appear to have injection molded bodies. Close examination of tenon ends reveal a 'seam'. They could be investment cast but that, it seems to me, would drive the cost way up. Investment casting is fairly complicated but, in large quantities, works well for metal. Injection molded metal could also be cost effective in very large quantities. Both of these topics, however, are speculation because, unless Don (or someone else) can come up with inside info, we don't have any hard facts about 'How'd they do that?'
Machining woodwind bodies from billets, as Beejay states, would probably be standard practice, with some modifications to suit the harder stock, for wooden instrument manufacturers. I'm guessing this would be the least costly way for a manufacturer to phase into new material processing methods without having to invest suddenly in totally new (casting/molding/turning, etc.) machinery. When a new product shows substantial public acceptance (big profits), they consider new machinery. When that shows significant acceptance the prices might come down a little.
|
|
Reply To Message
|
|
Author: Gordon (NZ)
Date: 2002-01-15 12:34
Clues?
Wooden clarinets and plastic Yamahas have screwed-in posts (pillars), Vitos, like most plastic instruments, have posts moulded into the plastic - and they knock out more easily than the screwed-in ones. Plastic Yamahas and many wooden ones have undercut tone holes, suggesting machining. Vitos, as far as I know, don't, again suggesting moulding.
|
|
Reply To Message
|
|
Author: Bob
Date: 2002-01-15 17:03
I speak as a retired Materials Engineer, Metallurgist with considerable experience. No, I'm not blowing my horn but just to let you know where I'm coming from. I hear much of the same confusion in the preceding messages that I heard during my professional career. I have no bone to pick with anyone but why anyone would call blocks of plastic billets is beyond me. Of course I'm not english. I have no knowledge of exactly how any clarinet mfgr. produces the stock from which clarinet bodies are machined. Most filled thermoplastic polymer "forms" are produced by injection molding but they could be compression molded also. A long "billet" ( clarinet section in length plus) could be extruded under compression which would not leave a "seam", but it could also be compressed longitudinally which might leave a "parting line" i.e. longitudinal "seam". And so on. Polycarbonate filled with the waste from machining clarinet wood stock would not be exceptionally difficult to machine per se.......however, there tricks to every trade. The machining of clarinet sections from "filled" polycarbonate is not a typical plastic fabricating operation. Most injection molded "plastics" are not machined at all....here I group all types of parts, not just musical instrument parts.
Therefore, you can imagine that the people who have been machining unfilled thermoplastic clarinet bodies are not advertising their methods to the world. Oh, investment casting is hardly the fabrication method that would be used on plastic clarinet sections as it is traditionally used only on metals. You might poll some privately owned "machine shops" in the Milwaukee,Kenosha and Chicago area for current advice.
|
|
Reply To Message
|
|
Author: ron b
Date: 2002-01-15 17:15
Absolutely, Gordon -
Some of the older Conns had screwed in pillars. I've repaired a couple of those that were knocked out. It seems, in my limited experience, that reeds, pillars and tenons are the most vulnerable parts of any woodwind instrument. I've yet to come across a wooden clarinet without undercut toneholes. Even though most clarinet bodies are probably molded, I'm positive they require some machining. Certainly, I can't imagine any way to fraize a tonehole than by machining (by hand or otherwise). It would be interesting to discover how they do thousands upon thousands of them(Yamahas), assembly line fashion, these days.
|
|
Reply To Message
|
|
Author: Gordon (NZ)
Date: 2002-01-20 11:01
I imagine a CNC milling type of machine could undercut tone hoes by running cone-shaped cutters (smaller diameter than the tone hole) around the bottom of the tone holes. At perhaps 5 seconds per tone hole the operation for the entire clarinet would take a couple of minutes. If a clarinet section was made from an injection moulded or extruded 'bar' (or billet, or whatever else it may be loosely termed) I imagine all the tone holes could be drilled and the tenons turned in another couple of minutes.
And the process would be much the same for the plastic, or composite, or timber instrument. I find it hard to see why the construction of the body itself should be an expensive part of production. I wonder how much propoganda we are subject to here.....
|
|
Reply To Message
|
|
The Clarinet Pages
|
 |
.jpg){kind=small}
.jpg){kind=small}
.jpg){kind=small}
.jpg){kind=small}
.jpg){kind=small}
.jpg){kind=small}
