The Talking Machine Forum — For All Antique Phonographs & Recordings

Got to love Pot Metal parts! Heard a thud and wondered what it was? Guess what it was a pot metal tone arm laying on my shelf. I had no idea these can nearly explode.

I ventured into radios a little, and found pot metal is no stranger there either, everything from dial drums to speakers.
I think Edison Diamond Disc and early Victor machines seem to be the way to go to avoid pot metal parts.

Has anyone here had any issues with pot metal parts exploding?

You'll find that a lot of good "Modern" Reproductions of the same parts are made of Steel or even Modern Grade Aircraft Aluminum I have found.

It's just a part of the "sickness" of collecting Antique Phonographs... That's why people don't balk too much at some Modern "Repro" parts made from non-original materials..as long as the other 90% of a machine is original...because it gets the machine going and it's better to have it running than not running..!!! ...even though the machine's value might be slight;y affected...

It's pretty normal.

)

Tony K.

Edison Collector/Restorer

Hello,

I'm one of those radio collectors who occasionally deals with pot metal. Here's link to an article from Radiolaguy that discusses the issue with pot metal including a dramatic incident of "exploding" pot metal!

https://www.radiolaguy.com/info/PotMetal.htm

Best regards,

Britt Abbott
Chesapeake, VA

All I know about pot metal is - never heat it up to loosen it up... I heated a piece that was stuck thinking that would get it to move... wrong ... I ended up with a pile of stuff that somewhat resembled melted solder. Lesson learned...

Take a can of compressed air, turn that upside down, and shoot the resulting frigid iceblasts out of the can's "straw" onto the affected metal. This shrinks it and it works better than heating. I used this to get the potmetal N reproducer out of the large carriage on my 1911 Model E Standard--we still had to replace it, due to age cracks on the dome and neck, but it came out in one piece!

I think Edison Diamond Disc and early Victor machines seem to be the way to go to avoid pot metal parts.

In addition to those machines, late Victrola 1929, 8-9 and 8-35 have much better metal in their reproducers than the previous ones after Victor discontinued the brass reproducers. Also Columbia Viva-Tonal machines don't have the pot metal issues that the earlier Columbia Grafonola's have.