Grinding Cast Iron

[THAWA]

What tool would you use to grind a piece of cast iron 5mm?

[206er]

a regular grinder
go slow to keep the heat down.

[BAC5.2]

In what application?

Do you have a flange that you need to grind down to 5mm thick, like a flange on the passenger side collecter?

If so, I'd use a large circular bench grinder, a new wheel, a steady hand. The biggest mistake you can make is using a piece of shit Harbor-Freight grinding disc. Quality will get the job done in 1/3 of the time.

A friend of mine had a 12" bench grinder, and that sumbitch would handle ANYTHING.

Just do like Jeremy said, go slow. You'll heat the iron to red-hot and you could warp it. Wear gloves! I've got a slice in a pair of mechanics gloves from that grinder I mentioned. They actually saved my finger from getting sliced up.

[THAWA]

I'm grinding a knuckle I only need 4-5 mm off of it. So like an angle grinder? Doing it on the car is much more advantageous than removing the whole thing.

[BAC5.2]

You need ro remove 5mm? An angle grinder with a fat ass wheel should do the trick.

You could try cutting it too, using an air cut-off tool and a really high quality wheel.

[206er]

oh a knuckle is probably going to be cast steel and on something that thick just fuckin go at it with an angle grinder.
the reason I said go slow on cast iron is not only will it warp but it will crack pretty easy if it is on the potmetal side of quality.

[corsair]

A quality angle grinder with a fat ass wheel should do the trick.

fixed it for ya Phil

[206er]

an $8 harbor freight angle grinder will last if you do a few mods to it and dont abuse it, and when they go it is usually brushes which are an easy fix.
but then you have actually purchasing a power tool at harbor freight on your conscience

[555BCTurbo]

I was actually taught in Machining School to never wear gloves when grinding...more people lose fingers when the gloves get caught in the grinder

I will vouch for the Angle Grinder and Quality wheel for this application...I honestly wouldn't worry about heat too much, because Knuckles are pretty stout, and it would take a lot of heat (i.e. rosebud) to heat it enough to cause cracking or warpage.