The trombone designed by a committee

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Posaunus
Posts: 5018
Joined: Mar 23, 2018

by Posaunus »

A friend sent me this article about the Martin "Committee" trombones from (apparently) 1939.

You may be interested:

<LINK_TEXT text="https://docs.google.com/file/d/0B5-_7UC ... VSOTg/edit">https://docs.google.com/file/d/0B5-_7UCbLfDqazJHUlZVeUVSOTg/edit</LINK_TEXT>
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JohnL
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Joined: Mar 23, 2018

by JohnL »

Hold on a minute...

the inner slide tubes are made of nickel steel?
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paulyg
Posts: 689
Joined: May 17, 2018

by paulyg »

Makes sense... I have a committee deluxe that has some plating wear on the inners, and it looks like there are flecks of rust on them.
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imsevimse
Posts: 1765
Joined: Apr 29, 2018

by imsevimse »

[quote="JohnL"]Hold on a minute...

the inner slide tubes are made of nickel steel?[/quote]

I have that model and the slide is perfect. My horn is in mint condition.

/Tom
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JohnL
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Joined: Mar 23, 2018

by JohnL »

[quote="paulyg"]Makes sense... I have a committee deluxe that has some plating wear on the inners, and it looks like there are flecks of rust on them.[/quote]
Is it magnetic? Not a conclusive test (LOTS of nickel will make steel non-magnetic), but a start.
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timothy42b
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by timothy42b »

[quote="JohnL"]<QUOTE author="paulyg" post_id="90407" time="1564072490" user_id="3299">
Makes sense... I have a committee deluxe that has some plating wear on the inners, and it looks like there are flecks of rust on them.[/quote]
Is it magnetic? Not a conclusive test (LOTS of nickel will make steel non-magnetic), but a start.
</QUOTE>

If magnetic, then it's steel. If not, still could be steel. Although I would have thought any steel you could easily draw a tube with would be magnetic.

So, on to the second test. Hit it with a grinding wheel and check the color of the sparks. Steel should give you those characteristic bluish white fireworks clusters.
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BGuttman
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by BGuttman »

I used to own a Committee. The inner slide did not appear to be steel. It was too light. Steel the thickness of the metal would have been much heavier.

I would not be surprised if the inner was nickel silver (which is a copper alloy and contains no silver).

Sadly, I no longer own the instrument and can't test it for you.
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JohnL
Posts: 2529
Joined: Mar 23, 2018

by JohnL »

Most inner slide tubes on pro horns are nickel silver. Possibly a typo?
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timothy42b
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Joined: Mar 27, 2018

by timothy42b »

[quote="BGuttman"]I used to own a Committee. The inner slide did not appear to be steel. It was too light. Steel the thickness of the metal would have been much heavier.

[/quote]

Are you sure?

This chart:

<LINK_TEXT text="https://www.machinemfg.com/density-tabl ... um-alloys/">https://www.machinemfg.com/density-table-of-metals-iron-steel-brass-aluminum-alloys/</LINK_TEXT>

lists brass at density of 8.8 and steel at 7.8. If the steel is the same thickness, it should be lighter?
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CharlieB
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Joined: Mar 29, 2018

by CharlieB »

Many thanks to Posaunus for the great historic information.

It is possible that Martin inners could have been steel at one time, as steel /nickel alloys were available.

<LINK_TEXT text="https://www.brighthubengineering.com/ma ... eel-alloy/">https://www.brighthubengineering.com/manufacturing-technology/74149-production-and-use-of-nickel-steel-alloy/</LINK_TEXT>
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BGuttman
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by BGuttman »

Nickel-iron alloys have been available for a long time as "stainless steel". Commonly used in surgical instruments and where corrosion is a problem.

The issue with using any iron alloy is the greater difficulty in drawing tubes (although most heat exchangers use stainless steel tubes) and the inner being quite rigid possibly creating a problem with the more flexible brass outer slide. It's also much harder and thus may make a rather strident tone.

Just noticed: I'm playing my Committee in my avatar :cool:
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Posaunus
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by Posaunus »

[quote="BGuttman"]I used to own a Committee. The inner slide did not appear to be steel. It was too light. Steel the thickness of the metal would have been much heavier.[/quote]

Steel – even with lots of nickel – is not denser than brass or "nickel silver."

Therefore a steel slide should not be any heavier than other slides with similar wall thickness. :idk: