Can a warped cast iron turntable be flattened?

[Jerry B.]

I have a cast iron turntable from a Victor M or MS that is obviously warped. Is it possible to flatten the turntable?

Thanks, Jerry Blais

[phonosandradios]

I always thought cast iron was quite brittle so I looked it up on google and found the following:

Compared to wrought iron or steel, cast iron is brittle, hard, and non-malleable. It can't be bent, stretched, or hammered into shape. Its weak tensile strength means that it will fracture before it bends or distorts.

There are ductile forms of iron but google also found this....

We give Keith Millis credit for creating ductile iron way back in 1943. He and his buddies Albert Gagnebin and Norman Pilling received US patent 2,485,760 and US Patent 2,485,761 for making ductile iron using magnesium (Mg) in the metallurgy (the metal composition or what was in the secret recipe) to get the graphite to line up into spheres.

I guess it pre dates 1943 so will probably be brittle so I wouldn't fancy your chances of flattening it without mishap.

[Jerry B.]

Thanks for your reply. It looks like my genuine Victor M turntable is scrap.

Jerry B.

[fran604g]

Thanks for your reply. It looks like my genuine Victor M turntable is scrap.

Jerry B.

I guess if it's scrap, then what do you have to lose by trying to slowly and steadily apply pressure and see if it can be straightened?

It would be a shame for it to break, but if I had no choice except throwing it in the scrap metal heap, I'd give it a shot. Maybe heating it with a torch could help convince it to flex a little? Just thinking out loud Jerry.

Best,
Fran

[phonosandradios]

I'm not sure if spot heating it would be a good idea. Years ago a relative asked me to help strip old lead paint off a victorian cast iron radiator screen. We used a heat gun on some of the intricate parts and it was only later that we noticed that there were some cracks in the iron. Looking back I should of realized that heating one spot of a brittle material is not a good idea. That was my experience anyway but I guess if you have nothing to lose.

[fran604g]

I'm not sure if spot heating it would be a good idea. Years ago a relative asked me to help strip old lead paint off a victorian cast iron radiator screen. We used a heat gun on some of the intricate parts and it was only later that we noticed that there were some cracks in the iron. Looking back I should of realized that heating one spot of a brittle material is not a good idea. That was my experience anyway but I guess if you have nothing to lose.

That's a reasonable point. After I posted I was curious if spot heat might be a problem from too much expansion in a small area.

Best,
Fran

[estott]

I would leave it alone and find a replacement.

[fran604g]

I did find hope for the possibilty of bending cast iron. It seems heating needs to be performed on the entire piece evenly. Still a crap shoot, I'd imagine, but who knows?

https://www.practicalmachinist.com/vb/g ... ty-138869/

[OrthoFan]

Hi Jerry:

Is the "top" of the turntable, itself, warped, or is the center portion which sits over the spindle (I forget what it's called) uneven. If it's the center portion, that could probably be repaired.

If the top is uneven, then a replacement, as estott notes, would be your best bet.

OF

[tomb]

Hi Jerry:

Is the "top" of the turntable, itself, warped, or is the center portion which sits over the spindle (I forget what it's called) uneven. If it's the center portion, that could probably be repaired.

If the top is uneven, then a replacement, as estott notes, would be your best bet.

OF

I was also wondering if you could shim or rework the hole to make it run true. Also if it needs a high even heat will a ceramic oven due. That is an oven that they use to glaze ceramics. I would have no idea of the heat temp. needed to cause it to be malleable or how to flatten it out or with out damaging it. Tom