The Talking Machine Forum — For All Antique Phonographs & Recordings

I own a Columbia 112 I picked up for free and I recently broke a small piece from the pot metal tone arm, after removing the pot metal horn I sent them off to a foundry who can reproduce them in cast aluminium for only £50 for the two!!

So why don't more people do this with pot metal issues? Its not very expensive, its easy and quick and you can choose the material it is made from making the gramophone or phonograph last for another 100 years by which time all other Columbia 112's arm and horn will be too brittle to use or just dust.

And pot metal reproducers such as the no4 or n05 could benefit from this greatly.

Any thoughts?

Where's this foundry? It sounds like a useful contact.

That sounds amazingly cheap! I'm no expert (far from it) but dimensions might need great care, as (1) if copying pot metal parts, they may have expanded since they were new and (2) casting involves some shrinkage.

It may be that the process will become very much more complicated if one is trying to replicate a component which calls for very precise dimensions and for which the original is swollen, blistered or otherwise distorted. A later Edison mandrel bearing or reproducer top might be an example, and I feel that sound-box backs (which Jake has mentioned) might raise similar problems. Nonetheless, a valuable and constructive suggestion on his part. I am sure we all look forward to hearing how this first project turns out.

Oliver Mundy.

As others have mentioned, using a warped swollen part as a pattern will only yield another warped, swollen part as a new casting. If your piece was simply broken, then you stand a better chance at success. The other factor is that many pot metal parts are also machined after casting. Getting machining done can be expensive. Castings can also be expensive if they require cores and core boxes, (in other words, if the castings are hollow or have complex shapes). Then there's finding a foundry and/or machinist who will deal with an individual.

It looks as if you lucked out on that last point. Also perhaps lucky if the piece you need is not complex in its shape and does not need machining after casting. In other words, it ain't normally that cheap or easy. I think you just got lucky.

Its an arm for a Columbia 112 portable, the arm is potmetal and sits into a brass bearing, and the horn which is fairly simple all I need to do myself is drill a few holes and cut thread into two of the holes.

Thanks for the questions, Jake

Jake, Great Job saving this Columbia. I'd bet you are one of the few collectors who would do something like this. More power to you and may you save many more gramophones in the future.

I'd love to see pictures.

Best,
Fran

I'll post pictures when i receive the parts back and im only 16 so understandably my budget is limited and i had wanted a Columbia portable with straight tone arm for a while now but had put it off due to the pot metal problems and seen as i got one for free i decided it was now or never to do it.

I bet having a Heinemann No. 10 tone arm cast with the spring loaded back bracket would be expensive.