Warped cast iron

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Warped cast iron

Post by EOsteam » Mon Dec 16, 2019 11:45 pm

I have a a cast iron piece which is a transverse equalizer bar. It will be machined flat to 0.25" thick. However, it is warped and if machined in the current state will be too thin in the middle. The metal I believe is cast iron and when I draw a file across it the file barley scratches the metal. Is there a way to heat the metal and flatten it before I move on to the machining? If so, how is this accomplished?

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Re: Warped cast iron

Post by Harold_V » Tue Dec 17, 2019 1:10 am

Cast iron is not known for its ductility, and lacks tensile strength, so my advice to you is to not try to straighten. It most likely will crack, heated or not.

That said, are you certain it's cast iron? Steel is cast as well, and would be similar in appearance. I would think it would be more inclined to be used for an equalizer, and it may even be a forging instead of a casting, as they typically display the same characteristics (draft), but have greater physical qualities. If it happens to be a forging, or cast steel, unless it's high carbon or alloyed and heat treated, you should be able to adjust it before machining.

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Re: Warped cast iron

Post by LIALLEGHENY » Tue Dec 17, 2019 7:32 am

If you have enough stock on an edge try a spark test. Hit it with a grinder, short orange sparks and you have cast iron, longer yellow sparks , you have steel. try the spark test against a known piece of cast or steel.


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