Best way to cut cast iron?????

Ed of all trades · Sep 4, 2012

I have a brake drum from a big truck that I want to make a forge out of. It is about a foot deep and I need to cut it down to about 6". It is about 1" thick? and 18" ? across. Any ideas:confused3: plasma cutter? ???

deereman75 · Sep 4, 2012

I would likely use an angle grinder with a 7 inch zip cut. I say that because that is all I have that will work. Torch won't cut it, and cast iron kills saw blades.

Baby Grand · Sep 4, 2012

Air carbon arc (gouging)?
I used one to cut stainless castings many years ago.
Cheap, effective and really scary - the noise and light show it made!
If you go this route, make sure you have a really dark filter in your helmet and nothing flamable withing 50 feet of the work.

Mark @ Everlast · Sep 4, 2012

Plasma would make the quickest work of the drum.

Gary Fowler · Sep 4, 2012

If you dont already own a heavy duty plasma rig that will cut 1" material which would be $$$$$, I would follow Deereman75's advice. A 4.5" zip cut disc will work as well as a 7" but it will burn thru a lot of discs cutting that 57" of linear cut. I might suggest that you could use it as is and just fill in the bottom 6" with fire brick rather than cut it down. Heck regular old clay will work to line a forge with also if you dont have fire brick

deereman75 · Sep 4, 2012

I personally find the 7 inch zip cuts to cut far faster then the 4.5 inch ones. It also seems easier to follow a straight line. Then again, not everyone has a 7 inch.

Soundguy · Sep 4, 2012

got a way to chuck it onto a drive that will make it run true? then a abrasive wheel of choice will cut it. probably the cleaner cut that gouging or a big salvegers gas axle

zzvyb6 · Sep 4, 2012

Ed of all trades said:
I have a brake drum from a big truck that I want to make a forge out of. It is about a foot deep and I need to cut it down to about 6". It is about 1" thick? and 18" ? across. Any ideas:confused3: plasma cutter? ???

A metal cutting abrasive wheel in a table saw will do the job nicely. Just roll it around the fence once it cuts through. Yeah, I know, there is iron dust and the saw cost me $150.

Ed of all trades · Sep 6, 2012

Thanks guys, I have a 4" grinder so I bought 10 cutting wheels for it. Used two so far and have a fair start, it will take a while, but does make a good cut. Have used these before but never on cast.