 The Clarinet BBoard
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Author: Tony F
Date: 2015-07-27 04:06
I've had several Amati's that had Bakelite bells, and I think the B & H 77 had one as well. They had a slightly granular semi-gloss finish and were quite light.
Tony F.
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Author: ClaV
Date: 2015-07-27 07:02
Bakelite is one of the least expensive plastics, used to produce massive items - tabletops, etc.
In a cost-effective process, the items are made by molding.
Due to shrinkage, any reasonable precision of the bore is not possible.
I have not seen bakelite items machined after molding (I have ~5 barrels in my collection and one USSR clarinet, which tormented few generations of young players).
Bells of student instruments would be the only part which makes some sense to make - robust and not critical for the precision.
Post Edited (2015-07-27 07:07)
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Author: Chris P
Date: 2015-07-27 10:33
Amatis normally had ebonite (hard rubber) bells which turned green over time (as did the gilt paste used to fill in the logos). B&H "77" clarinets also had ebonite bells which discoloured.
Ebonite smells like rotten eggs due to the sulphur content and will tarnish silver plate black very quickly, so ebonite instruments normally had nickel plated keywork as that wasn't affected by the sulphur, but ebonite has made a huge comeback what with the more recent wave of Chinese imports. Older Chinese imports, mainly Lark and Hsinghai, were also made from ebonite.
Good quality mouthpieces are generally made from ebonite for both clarinets and saxes.
There used to be loads of old Russian clarinets and oboes on eBay, all with Bakelite bodies and presumably nickel plated Mazak keywork - I was tempted to buy one of the oboes out of curiosity.
Perhaps the heaviest woodwind instruments ever made were the older Bundy Resonite bassoons that were made entirely from Bakelite until they changed to the lighter ABS resin.
I don't know if Bundy or Vito ever made bass, contra-alto (or Vito BBb contrabass) clarinets from Bakelite, but if they did they'd also weight a ton.
Former oboe finisher
Howarth of London
1998 - 2010
The opinions I express are my own.
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Author: ClaV
Date: 2015-07-27 15:25
Bakelite density is ca. 1.36 g/mL (cm cubed).
Grenadilla (Dalbergia melanoxylon) density is 1.2-1.25 g/ml.
Delrin (one of the favoured synthetic thermoplastics for clarinets) density is 1.4 g/ml.
Delrin clarinets can be made lighter using thinner walls, since Delrin is strong.
So the main reason that bakelite clarinets are heavier is inferior mechanical properties of bakelite (and molding process) that necessitated thicker walls.
Those Soviet bakelite oboes and clarinets were one of the factors that there are so much less Russian clarinetists known compared to violin and piano players
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Author: ClaV
Date: 2015-07-28 07:06
Dear Silversorcerer,
You wrote 3 messages with many letters.
I will be happy to support my statements word by word, as long as it will work for your satisfaction (and/or understanding the science).
First of all, bakelite is a thermoset, a type of polymer materials produced by irreversible reaction of two monomers, one of which is multifunctional, so the system is heavily cross-linked, and as a result non-uniform (e.g. speckles/grains on your multiple photographs). It is important, since properties of thermosets are inferior in many aspects due to this non-uniformity, and bakelite is a textbook example.
For bakelite, the monomers are formaldehyde and phenol. The reaction is poorly defined and it does not lead to well-defined linear polymer chains (as with many thermoplastics, for instance ABS).
Second, in thermosets, some of the monomers typically do not completely react, which practically results in heavy smell of fresh bakelite. Formaldehyde is quite toxic and there are strict regulations in place for handling it.
Practically, it means that bakelite takes efforts to produce safely and also, importantly, to handle safely when freshly produced. It should just be one more reason why no one makes bakelite clarinets now.
Here is one interesting article to illustrate the point about the safety of bakelite production back then: http://www.intelligencer.ca/2008/12/06/bakelites-toxic-legacy-cant-be-left-to-simmer
Surely, old bakelite samples, that you handle, lost most volatile compounds over the years, but when scratched/machined, you get the unmistakable phenol smell.
Now to the inferior mechanical properties. Bakelite is not uniform and while generally strong (as expected from cross-linked polymers), the weak links form breakage points. As I mentioned, I have few bakelite barrels, some of them are chirped. Just for you (since you seem to like empirical evidence) I chirped one more - very easy to do, very poor material compared to grenadilla and decent plastic, like ABS. Again, that is what called inferior mechanical properties.
To make it more complicated for properties characterization, bakelite, as most of thermosets, is typically used with fillers: partially to reduce the cost and partially to alleviate some non-uniformity. One typical filler for bakelite is a wood dust. Another common filler used to be asbestos fibers, which give better properties in fact, but hardly a material of choice today.
Sure, better fillers can make bakelite a better material but at a cost; and most importantly there are better materials than bakelite, e.g. polyester, nylons, which give superior materials, for example as a polymer matrix (reinforced) with carbon fibers. These materials based on carbon fibers, I believe (and here is just my reasonable thinking), would be superior for clarinets, as well.
Now, if we get to the values for mechanical properties, the data for bakelite give the range, e.g. tensile strength 5-9 ksi (5,000-9,000 psi). Here for instance, page 19: http://engr.bd.psu.edu/rxm61/METBD470/Lecture/PolymerProperties%20from%20CES.pdf
For Delrin, manufacturers specify 9,000 psi: http://www.sdplastics.com/delrin/delrin%5B1%5D.pdf
The weak link (smallest values) would be more relevant for catastrophic failures. I will be happy to discuss it more.
Finally, there is a great difference between "not shrinking and warping" referring to the post-transformation of the item already made and shrinking upon molding. For the molding, with all the polymers, the shrinkage is substantial due to polymerization reaction (and effective "compactization") so it is quite challenging to make precise molding (quite relevant for plastic student clarinets). Again, I will be happy to answer your further questions in more detail.
Very briefly, there were not enough East German clarinets for students in USSR (they were quite expensive and were not produced in large enough quantities).
Post Edited (2015-07-28 07:13)
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Author: ClaV
Date: 2015-07-28 16:56
Silversorcerer wrote:
> Are phenols and formaldehyde more carcinogenic than
> acrylonitrile? I just wondered? In fact it appears that all
> three of the constituents that make up ABS are carcinogenic. I
> am sure that contributes to the superior mechanical properties
> of ABS, if there are any.
>
Good questions!
The key to this is that bakelite is a thermoset, again.
In bakelite, by a nature of the polymerization process, it is difficult to completely react monomers. Some monomers and the oligomers (just few monomer molecules reacting) remain. That is corroborated by phenol smell upon scratching/cutting.
In a modern polymerization process, the reacting monomers can be handled efficiently, if reacted fast and completely (the case of ABS and other good plastics). No acrylonitrile remain in ABS. Even upon heating acrylonitrile is not the main decomposition product. It is worth to mention that good carbon fibers can be produced by pyrolysis of poly(acrylonitrile) fibers (common acrylic fibers that if not by knowledge but by all previous experience are safe to handle/wear).
Now to mechanical properties and thermosets again.
In ABS, long linear chains are formed - regular and strong. ABS is smartly engineered with monomers imparting rigidity (styrene) and elasticity (butadiene and acrylonitirile imparts good chemical stability - a bit simplified, but relevant picture. To give a relevant example, simple poly(ethylene), effectively a hydrocarbon, if produced in very long chains (UHMWPE) becomes stronger than Kevlar. So the length of polymer chain (the number of monomer molecules combined in a chain) is the key to superior mechanical properties, which works well in the case of ABS.
In contrast, bakelite polymerization process is a mess, and there is no uniformity, which creates a lot of weak links and imposes brittleness. In some properties bakelite is closer to ceramics than polymers.
> It is interesting that one chooses to characterize a number of
> differences in material properties as "inferior". Whether these
> properties make something inferior depends on the use. Given
> the high demand for bakelite at the time, it must have been the
> superior material for many of the uses it served. Without
> characterizing any material as inferior, we could review the
> differences that might be valuable.
>
> 1) Weather neutral.
> 2) dimensional stability
> 3) Durability constant over a wide temperature range.
> 4) consistently machinable to high tolerances
> 5) resistance to chemical damage, chemically neutral.
Did you have a chance to look through the file with bakelite properties that I referred to for the mechanical properties?
1) I am not sure what is it exactly; does it effectively refer to chemical stability at common conditions of use (weather can be different)?
2) See below
3) Bakelite is quite good for thermal stability. Is is crucial for clarinets?
4) If bakelite chirps, how can it be easily machined to high tolerances?
5) Chemically stability of bakelite is relatively poor, bakelite is susceptible to acids
> You keep talking about the problems of shrinkage during the
> molding process
Yes, during typical polymerization, there is a substantial shrinkage.
> It seems though that the the only material that is
> superior is one that can be accurately molded to specifications
> as opposed to machined to specifications.
Very true, to my knowledge and understanding and that is great that we had a chance to discuss it. Molded plastic clarinets are easy to make at a moderate cost, as well as moderate tolerances. Post-processing can be made to bring plastic clarinets into professional grade, but at appreciable cost.
>
> There are machining marks on all of the bakelite parts I have
> seen. Are ABS clarinets molded completely as a finished
> product? Does this create an instrument that is as consistent
> in dimensions as those that are the result of machining to
> dimensional tolerances?
A good question. The shrinkage is there. With stronger and uniform an ABS, it is easy to factor it out in molding design. Again, I do believe that the best practice would be to machine precisely the bore and the toneholes after molding. There micron tolerances (at least ca. 10 microns) become important. Molded instruments would be difficult to make to such high tolerances.
> A more favorable history of bakelite, which shows it being
> sawn, machined in every conceivable way and polished is given
> here:
> http://www.elvenkrafte.com/bakelite%20presentation.htm
>
> Obviously the problem with bakelite chirping could be very
> distracting during quiet passages in compositions. Be careful
> not to chirp your bakelite clarinet.
That is nice sentimental story. Importantly, do they give machining tolerances?
Or by this logic, is anything cuttable and polishable good for clarinets?
I do believe in good craftsmen - people can make great things. But in some cases, it is much more difficult and not cost-effective.
The USRR bakelite clarinet that I have is molded, there is chirping with the use, the bell is cracked. Does bakelite make a good material for clarinet? No!
Can decent clarinets be made out of bakelite, if careful and patient - perhaps.
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Author: Chris P
Date: 2015-07-28 18:13
As I've said before, older Yamaha, Vito and Bundy clarinets as well as B&H Regents from the '60s and '70s were made from Bakelite. These are injection moulded and then the toneholes, pillar holes and other slots and recesses are cut afterwards. There will always be an element to hand finishing as the mould lines have to be removed and polished out, so they will have flat spots on either side of the joints.
If you learnt recorder at school in the UK back in the '50s through to the '70s, chances are you may have played a Dolmetsch Dolomite Bakelite recorder. A lot of recorder enthusiasts like them due to the hardness of the material which made for good voicing, but the problem with them is the tenons and sockets can crack and when the mouthpiece gets scratched or chipped, it made that classic Bakelite smell.
But plastic recorder makers (like makers of other entry level plastic bodied woodwinds) have since moved to using ABS resin as it's more user friendly (and probably easier to injection mould and finish) even though it's not as dimensionally stable as other more dense plastics which is fine for recorders as they have very few to no moving parts on them, but a problem for piccolos, clarinets, oboes and any other woodwinds with metal keywork (especially the much larger ones like alto, bass, EEb and BBb contrabass clarinets) as allowances have to be made for thermal expansion/contraction of the plastic as the metal keywork isn't going to shrink to expand at anywhere near the same rate as plastic, so keywork has to be a sloppy fit between the pillars which is relative to the length of the key barrels.
Former oboe finisher
Howarth of London
1998 - 2010
The opinions I express are my own.
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Author: ClaV
Date: 2015-07-28 20:14
It seems, Silversorcerer, you are trying to get personal in our dialog.
I made the arguments that bakelite is inferior material and supported them.
If you have a beatifully sounding bakelite clarinet, the onus will be on you to demonstrate it. All the facts that bakelite clarinets are no longer made, that ABS and delrin are superior materials are against it.
The bakelite USSR clarinet that I have is not worth playing. I am content with my Noblet Artist which I restored for fun (and for the record my playing abilities are extremely limited to bring them into the discussion).
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Author: ClaV
Date: 2015-07-28 20:32
ABS was first developed industrially in 1948, which coincides well with the production of the first Bundy in 1948 and the era of plastic clarinets. So I always thought that Resonite is ABS-based, though Resonite was just a tradename and Selmer could in principle use any plastic material over the years.
Post Edited (2015-07-28 20:34)
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Author: Chris P
Date: 2015-07-28 20:39
Same with Vito and their Reso-Tone clarinets - they were initially made from Bakelite then they changed to ABS sometime I presume in the '70s like others did. Reso-Tone just being a trade name as opposed to being a specific material.
Former oboe finisher
Howarth of London
1998 - 2010
The opinions I express are my own.
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Author: ClaV
Date: 2015-07-30 01:44
Silversorcerer,
My practical impression of bakelite were based on this clarinet plus 4 bakelite barrels that I have.
Also Chris mentioned that early plastic clarinets were bakelite. It surprised me quite a bit. I've seen few old Vito, Bundy and Yamaha, but I have not encountered bakelite ones that may very well indicate that they did not survive that well compared to ABS ones.
Now for the upside of bakelite. In my search for the bakelite properties, the range of values is always given with the upper values comparing well to ABS and Delrin.
It tells that the defect-free bakelite can be a very good material. Bakelite definitely has a good stability, light stability is much better compared to Delrin.
Also,there were not much studies how bakelite behaves with aging; these types of polymer materials can improve. It seems many people happy with old bakelite items compared to hard rubber.
Quite closely related to bakelite are epoxy resins.
Epoxy resins in combination with with wood or carbon fibers make a very good material that is, from what I understand, is close to how Buffet makes Greenline clarinets.
For the sound of bakelite, all my experience with barrels - grenadilla, cocobolo, ABS, hard rubber, metal is that the dimensions matter the most, then roughness and only then quite subtly (if any) - material.
Those bakelite barrels , that I have, are likely from older student clarinets (no markings). They are wider and no bore taper.
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Author: Ursa
Date: 2015-07-31 00:07
Silversorcerer, I have two examples of the bakelite Noblet Normandy 11 from the early 1950s that may be of interest to you; shoot me an e-mail for details.
Post Edited (2015-07-31 00:09)
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