Hardest material possible to cut?


Sorry for the noob question and if it was answered multiple times already!

I’m just starting to build my first MP NCN and I’ll be using 25mm 2,00mm walls 304 SS (0,08" walls)

I know that it can work in aluminum without any problems.

Could it be possible to cut 3mm (1/8" or 0.12") iron plate (not SS, not steel, ordinary iron sheet)

I would be using 500W or maybe even 600W spindle with regulated speed (I’m aware that lower RPM in this case would mean less torque that’s why I would even go for 600W spindle)

Time is not an issue for me! If it takes few hours to make a cut of overall length of 3-4 feet, so be it.
Of course, if speeds so slow are possible without destroying tool bit before first job is done.
I would use thinnest bit possible for the job.

Is something like that possible with this machine?

Steppers would be 84oz.in

Thank you!


My first guess would be no… Those hard metals are a different beast all together.

I will say 98% no.

2% maybe on a tiny machine set up a little differently but you are talking 3-4 foot cuts, no way, that would be tough even in aluminum. Do some searching on cnc machines designed to cut steel and look at how many zeros are in the price tag.

The more zeros, the harder the material you can cut.

Maybe I’ve expressed myself incorrectly, English is not my first language.

Outer measures of the MP CNC that I plan to build are 60x80cm (24" x 32")
That would give 35x55cm (14" x 22") work area if got measures correctly.

So, I didn’t mean 3’ to 4’ cuts in a straight line but all around the whole shape (outer edge of the shape)

What is the limiting factor?
Frame rigidity?

And I don’t have any interest in cutting steel.
3mm 1/8" iron sheet is top for me


I wouldn’t call it impossible to be completely honest, even though I haven’t tried iron plate myself, I’ve seen trochoidal milling work magic on Aluminum, it cuts through it without any sort of effort.

Have a look at this video by Christian, the creator of Estlcam, and see what he cuts with a relatively “soft” machine: https://www.youtube.com/watch?v=ORJ-Q3TFW5o

This will take a while of course, but if time is a non issue, then I’d say that it could be done to some degree with the right tools, speeds, and feeds.