Hi there,

In the next week or so, I'm going to be machining some cast iron parts on my mill using a 6mm endmill. I need some advice.

My mill only has a max spindle speed of 2000 RPM. Based on this (and the fact that my mill is only a small Sieg X1 micro mill), what sort of feedrates should I be using to machine the cast iron (obviously only approximate)?

I also read somewhere on the net that little to no coolant is required for cast iron. Is this true? It would be ideal if it is, as I don't have coolant on my mill. Would the occasional squirt of oil by hand be beneficial?

Thanks
Warren

about 1000rpm, 2-4ipm I am guessing, and no, you dont need coolant. cast iron is flakey and sandy so i dont know how long your tools will hold up.

Jon

Cast cuts really nicely - not the greatest of surface finishes though.

Cover your machine and adjacent areas with something. It's a mess to cut....imagine ground up pencil lead all over your shop....

Scott

Warren, I just did some machining on a head, and they are right, it cut very easy, don't use coolant (gummy mess) It was a piece of cake and does not require a lot of horse power, you should get along fine.

If you are using a carbide cutter 4 flute you probably could double the rpm and feed, 2 flute carbide you could increase the RPM some but not much on the feed. HSS in a 2 Flute is showing less then 2 IPM and 874 RPM so Jon's 2-4 X 1000 RPM is pretty close.

These figures are not from experience but what I am getting from ME Pro software, usually a bit conservative, so it is great for us not so experienced. :)

Ken

Hi there,

Thanks for the replies, at least I now know where to start with the endmill.

I was wondering if anyone knew how well grinding works with cast iron as well - using something like a dremel rotary tool. I intend to grind the surface once I have machined it.

Thanks
Warren

Using aluminum oxide grinding wheels worked great for me with cast iron.