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Re: This year's designer colours.....

Posted: Wed Jan 17, 2018 2:03 pm
by Steve Bliven
I read the article you provide. Is the "hard rubber" described there the same as "ebonite" that is mentioned in this thread?

Are there metals that hard rubber/ebonite does not discolor or tarnish?

Thanks and best wishes.

Steve

Re: This year's designer colours.....

Posted: Wed Jan 17, 2018 2:08 pm
by Geoffrey Ellis
Yes, the hard rubber is ebonite. When it was first invented (I think 1844? Don't quote me on that...) by Charles Goodyear it was called "Vulcanite". Basically vulcanized hard rubber. Rubber sap + linseed oil + sulfur, bake at high temperature and voila! Hard rubber.

Re: This year's designer colours.....

Posted: Wed Jan 17, 2018 3:39 pm
by jemtheflute

Re: This year's designer colours.....

Posted: Wed Jan 17, 2018 3:49 pm
by jemtheflute
Hammy has a nice blog about Ebonite which quotes Rockstro at length extolling its virtues and also giving some dates for its use in flutes.

http://hammy-flutemaker.blogspot.co.uk/ ... e.html?m=1

Re: This year's designer colours.....

Posted: Wed Jan 17, 2018 4:35 pm
by Geoffrey Ellis
jemtheflute wrote:Hammy has a nice blog about Ebonite which quotes Rockstro at length extolling its virtues and also giving some dates for its use in flutes.

http://hammy-flutemaker.blogspot.co.uk/ ... e.html?m=1
Thanks for that link! Great blog post--I hadn't read that evaluation by Rockstro, which does sum it up nicely. However, my first ebonite headjoints are going out as we speak to a variety of professional players who have played my wooden versions and I'm interested to hear their evaluation.

Re: This year's designer colours.....

Posted: Wed Jan 17, 2018 6:42 pm
by jemtheflute
I notice Rockstro mentions there being lead as a component of the Ebonite he knew, but the Wikipedia article doesn't mention lead even with regard to early Ebonite.

Re: This year's designer colours.....

Posted: Wed Jan 17, 2018 7:06 pm
by Geoffrey Ellis
jemtheflute wrote:I notice Rockstro mentions there being lead as a component of the Ebonite he knew, but the Wikipedia article doesn't mention lead even with regard to early Ebonite.
I missed that on the first read--lead?? I've never heard that before in reference to the recipe and I can guarantee the modern stuff doesn't have it! I wonder if Rockstro was simply mistaken or misinformed.

Re: This year's designer colours.....

Posted: Wed Jan 17, 2018 7:42 pm
by kkrell
jemtheflute wrote:I notice Rockstro mentions there being lead as a component of the Ebonite he knew, but the Wikipedia article doesn't mention lead even with regard to early Ebonite.
All I found were ebonite casings for lead/acid batteries contaminated with lead (ebonite is recycled into other uses, such as asphalt):

https://www.google.com/patents/US5127963
https://trid.trb.org/view/363458

Wait...
http://www.fountainpennetwork.com/forum ... ck-rubber/
"So, after some more reading it seems likely that lead(II) sulfide would have been used in early ebonite products as a black dye. It seems that this lead compound is not soluble to the toxicity is probably a lower risk, but I could be totally wrong this is just a little bit of my reading "

http://www.fountainpennetwork.com/forum ... rd-rubber/
"Let's start with the safety issues. David Broadwell is right on this point. The old red hard rubber formulas incorporated not only mercury in the form of the mineral vermillion, or cinnabar, but also minium, or red lead, and litharge, or yellow lead, and golden and scarlet antimony. All these heavy metals are highly regulated and restricted in the workplace today, and that makes the old formulations of yesterday impossible."

https://books.google.com/books?id=D_ReA ... or&f=false
"Vulcanization stabilizes and hardens rubber. Vulcanization using sulfur, white lead, and heat is the very heart of the modern rubber making process."
"lead to increase heat resistance"

***Edited to correct fingers crossing on the keyboard.

Re: This year's designer colours.....

Posted: Wed Jan 17, 2018 7:47 pm
by Geoffrey Ellis
kkrell wrote:
jemtheflute wrote:I notice Rockstro mentions there being lead as a component of the Ebonite he knew, but the Wikipedia article doesn't mention lead even with regard to early Ebonite.
All I found were ebonite casings for lead/acid batteries contaminated with lead (ebonite is recycled into other uses, such as asphalt):

https://www.google.com/patents/US5127963
https://trid.trb.org/view/363458

Wait...
http://www.fountainpennetwork.com/forum ... ck-rubber/
"So, after some more reading it seems likely that lead(II) sulfide would have been used in early ebonite products as a black dye. It seems that this lead compound is not soluble to the toxicity is probably a lower risk, but I could be totally wrong this is just a little bit of my reading "

http://www.fountainpennetwork.com/forum ... rd-rubber/
"Let's start with the safety issues. David Broadwell is right on this point. The old red hard rubber formulas incorporated not only mercury in the form of the mineral vermillion, or cinnabar, but also minium, or red lead, and litharge, or yellow lead, and golden and scarlet antimony. All these heavy metals are highly regulated and restricted in the workplace today, and that makes the old formulations of yesterday impossible."
Great Scott! Well, apologies to Rockstro. Our not-so-distant ancestors did have a penchant for using things like lead and mercury in very scary ways. Mercury ointments for venereal diseases for example. The ebonite manufactured by SEM is supposed to be certified food-safe, so I'm guessing they've changed the recipe. But I had heard that some of the original ebonite colors from back in the day were no longer possible and I'm guessing that is because you only get them by putting some sketchy ingredients in.

Re: This year's designer colours.....

Posted: Wed Jan 17, 2018 7:58 pm
by kkrell
More:
http://test.woodwind.org/clarinet/BBoar ... 1&t=164160
"Author: Terry Stibal
Date: 2004-12-01 17:15

The early synthetic clarinets were made of a mixture containing natural rubber, sulphur (for the vulcanization aspect), carbon black (for the color) and lead (for God alone knows what reason; back in the day, there was added lead in a lot of industrial products). Same general compounding as the old black bowling ball, same density and so forth."

I'll stop now, but did see other references not quoted here. Seems that lead was used as either (or both) a coloring and hardening agent in the process of vulcanization with some manufacturers of ebonite items.

Re: This year's designer colours.....

Posted: Wed Jan 17, 2018 8:04 pm
by kkrell
Geoffrey Ellis wrote:But I had heard that some of the original ebonite colors from back in the day were no longer possible and I'm guessing that is because you only get them by putting some sketchy ingredients in.
Yes, it particularly looks as if the pen-turning and restoring community bemoans the difficulty in matching the reds of old.

Re: This year's designer colours.....

Posted: Wed Jan 17, 2018 8:35 pm
by jemtheflute
Good research, guys. I was wondering if Rockstro was mistaken, but it seemed unlikely on a matter of that kind.

Re: This year's designer colours.....

Posted: Wed Jan 17, 2018 11:14 pm
by paddler
Ebonite has been (and still is) widely used for mouth-pieces for instruments, such as clarinets, and for pipes (smoking, not musical). So, there seems to be a sizable community out there that still considers Ebonite to be "safe" to put in your mouth. Of course, that doesn't necessarily mean it IS safe (and if your health was you primary concern you probably wouldn't be smoking a pipe in the first place) but as flute players we have a little less exposure to it than those uses.

The thing that has put me off ebonite for flute making in the past has been concerns about longevity, in particular, discoloration issues over the long haul. I have a couple of Ebonite antique flutes that had faded to an ugly greenish brown color before I got them. My understanding is that this is a common reaction of Ebonite under UV exposure. I have yet to find a good way to reverse this, other than by removing the surface layer and refinishing. Various restoration products I have read about, including shoe polishes, all involve toxic substances and would not be appropriate for flutes. I don't know how long it takes for Ebonite to discolor like this, but given enough time (and judging by my antiques, 100 years is more than enough) discoloration seems inevitable.

Perhaps this can be addressed ahead of time by coating Ebonite, but I don't know for sure. Regular application of a product such as renaissance wax, may retard this process sufficiently, but I'm not sure how safe that would be for the user's health either. In fact, I just read that renaissance wax contains a small amount of benzene, which is carcinogenic.

Re: This year's designer colours.....

Posted: Thu Jan 18, 2018 2:29 am
by Terry McGee
Paddler, the green tinge on old ebonite is only skin deep, and can be polished off using Brasso.

And while you're at it, fix up any CDs you have that won't track....

http://www.mcgee-flutes.com/scratches.html

Re: This year's designer colours.....

Posted: Thu Jan 18, 2018 5:58 am
by AaronFW
Terry McGee wrote:Paddler, the green tinge on old ebonite is only skin deep, and can be polished off using Brasso.

And while you're at it, fix up any CDs you have that won't track....

http://www.mcgee-flutes.com/scratches.html
Um, Terry. I've got to point out the article is a little confusing. There is a big red "Caution! Since writing this, I've been advised that Brasso have changed their formulation and the new stuff will damage rather than repair your CD's. ... " but then there is a postscript that says
"It's now many years since I wrote and published this article. Seems like not much has changed however. A recent study of the various fancy products now available for fixing scratched CDs reveals that they found Brasso is still the best! "

It is hard to tell which statement is most recent. A time-stamp or the removal of one of the statements would help.



Paddler (the following is a joke on Rockstro and not intended to be particularly helpful), I'm not sure if you saw the article with the quote by Rockstro, but I think Rockstro's 3rd point may address the issue. http://hammy-flutemaker.blogspot.co.uk/ ... e.html?m=1
Thirdly, an ebonite flute invariably improves by judicious use.
I think the flutes just have not been played judiciously enough.

(For the record, I thought Rockstro's other comments were useful. But this one gave me a laugh and had no explanation as to what he meant.)