[quote=bellend post_id=79715 time=1551727800 user_id=82]
"you could even duplicate the chemistry of the brass Earl used"
And what exactly is that fabled to be?? ............... from the Harry Potter foundry ???........
Given that the largest component on the basses was actually fabricated by Conn ( bell) and on at least one so was the slide or did they use 'magic metal' as well.
Cartridge is brass is BRASS FOR CARTRIDGES........... what are modern shells made from......Cartridge brass
If he bought old stock it was probably because it was cheap
Sorry to be the voice of skepticism but people get carried away with all this B.S.
Several years back I submitted the following question to The Copper Development Agency to try and establish if there was any factual evidence for the various rumors and stories that abound .
Below is the response to Case No. 167158
Your question was: Dear Sir / Madam, I am trombonist who has also been involved in the manufacture of brass instruments. Over the years have been told anecdotally on numerous occasions that the composition of Cartridge Brass changed around the period of the second world war and that instruments produced before this supposed change took place are Superior in tone to ones made after. I was wondering whether you could shed any light on this and tell me whether there actually was any change in the composition and or manufacturing process for this alloy at any point during the last century?
Yours faithfully,
A. Hutchinson
Response: Andy,
I have been involved in the US copper and brass industry for 48 years and am not aware of such a change ever being made. The deep drawing properties of Cartridge Brass is a function of the composition and the processing
in particular the penultimate anneal.
It is possible that the nominal composition 70/30 Cu/Zn was pushed to the high side for zinc in an attempt to conserve copper which was a critical metal during the war. The US penny in 1943 was minted as a zinc coated steel coin to conserve copper.
There are several histories on copper and brass, one by a note US metallurgist, Cyril Stanley Smith comes to mind. You could also check with the CDA affiliate in the UK at:
Copper Development Association
5 Grovelands Business Centre
Boundary Way
Hemel Hempstead
Herts HP2 7TE
UK
Phone: +44 (1442) 275 705
Fax +44 (1442) 275 716
E-mail:
[email protected]
Angela Vessey,
Director
I will continue to search for information and if I find anything I'll get back to you.
Regards,
Lou Lozano
Metallurgical Consultant, CDA
Interesting what Mr Louzano sais about the zinc content may be beeing pushed to the high side to preserve copper. However given that the tolerance range for the alloy is quite tight at:
Chemical Composition for C26000
(%max., unless shown as range or min.)
Cu Fe Pb Zn
Min./Max. 68.5-71.5 .05 .07 Rem.
Nominal 70.0 - - 30.0
Note: Cu + Sum of Named Elements, 99.7% min.
Having the zinc content at the top figure can't change the workability of the alloy too much otherwise it would have become unsuitable for it's primary purpose......making cartridges.
Just sayin'
BellEnd
Andy!.. You are talking about cartridge brass only, but a lot of discussions about old Conn bells is about whether or not they used cartridge brass or another variant of Yellow brass.. I have heared the terms "french brass" and also "Conn brass" in similar discussions before.. All i know is that the bell of a 1934 Conn 70 H i used to own had a darker colour than the rest which looked more like standard Yellow brass (cartridge brass?).. Why would they use darker brass for the bell than the rest of the horn..?...