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Columbia switched from plated brass to pot metal trunnion assemblies at some point in the production run for first style ATs. I am interested in getting a good pre-pot metal first style AT trunnion assembly--either straight sale or giving an excellent (not pot metal) Columbia Model A trunnion assembly I have in trade.

Clay

Clay,
I believe that Jean-Paul Agnard has an excellent reproduction trunnion assembly for your AT. Check him out.
Harvey Kravitz

Phonofreak wrote:Clay,
I believe that Jean-Paul Agnard has an excellent reproduction trunnion assembly for your AT. Check him out.
Harvey Kravitz

Thanks Harvey, but he doesn't. I tried that. You'd think somebody would make them, given how common potmetal failure is, but I can't find a repro anywhere.

Clay

Can you post a picture of it? I have some Columbia parts that go to that machine, but I am not familiar with them. If I have it, you can have it.
Ronnie

Amberola wrote:Can you post a picture of it? I have some Columbia parts that go to that machine, but I am not familiar with them. If I have it, you can have it.
Ronnie

Sure. Here is a picture of the assembly off on a Columbia A. The one for the A does not fit my AT, but they look almost the same. It is the assembly that slides along the cover for the feed screw and carries the reproducer and the horn along as the cylinder plays.

Clay

FloridaClay wrote:

Amberola wrote:Can you post a picture of it? I have some Columbia parts that go to that machine, but I am not familiar with them. If I have it, you can have it.
Ronnie

Sure. Here is a picture of the assembly off on a Columbia A. The one for the A does not fit my AT, but they look almost the same. It is the assembly that slides along the cover for the feed screw and carries the reproducer and the horn along as the cylinder plays.

Clay

I will look through my parts and see if I have it.

Clay,

I've always been under the impression that the A and the AT used the same upper casting and that the carriages/trunions were interchangeable. Could you describe how your assembly doesn't fit?

Thanks!

George P.

phonogfp wrote:Clay,

I've always been under the impression that the A and the AT used the same upper casting and that the carriages/trunions were interchangeable. Could you describe how your assembly doesn't fit?

Thanks!

George P.

George, I bought what was represented as an A trunnion from a fairly well known dealer with exactly that hope, as just looking at pictures they seem the same, but alas it did not work. Here are some pictures, with the good "A" trunnion mounted on the right and the original not-so-good potmetal one on the left.

One more possibility rears its ugly head as well. When I removed the upper works to install the trunnion I noticed that 3 out of the 4 holes for mounting the upper works to the top plate are double, i.e., there are 2 holes very close together. This leads me to wonder if in fact the top works are not really the original AT Type 1 upper works and were from a different model added on by somebody somewhere in the past rather than correction of a drilling error at the factory.

Clay

P.S. The serial number is 241019.

Clay, I read that the early AT had the raised mandrel and the late AT had the lowered mandrel. Jan

phonogal wrote:Clay, I read that the early AT had the raised mandrel and the late AT had the lowered mandrel. Jan

Nope, just the opposite, at least according to Hazelcorn's Columbia Phonograph Companion, Volume I. It is the Type 2 that has the high trunnion, and from the pictures that trunnion's design and construction are very different from either of the ones shown above. Hazelcorn relates that the high trunnion was one of two major improvements made by the Type 2. (The second improvement was the introduction of the #5 reproducer.)

Clay