Smallest Diameter End Mill?

The smallest diameter available is 0.4 mm. I've used 1 mm and the break pretty fast. In the forum some user do use 0.8 mm. The stability decreases rapidly with smaller diameter!

I have 0.3mm endmills, but they have to wait for a better setup before I give them a try.
You need a motor with as little play as possible and of course high speed. So, my Proxxon is out of the game.

But with these little tools you can't do deep cuts of course.

What do you plan to use them for?

I work with not smaller than 0.6mm.
For nice pics in bicolored engraving plates.
:woohoo:

Thanks for the info.

MagIO2, hoping to use them on scale models, adding separation lines between sheet metal panels, control panel buttons etc.

Hi

For fine separating lines you could use a V Bit - with a 20 degree V bit you can achieve very fine lines.

Yep, with a v-bit you can go down to 0,1mm. But still you get best results at high rpm.

remember with a V cutter - at the cutting tip... the cutting speed is in fact 0 RPM. So some part of the tip will, in theory, always be scratching.

Smaller cutters are extremely sensitive to vibration. And you need really high RPMs. way higher than the RPMs the STEPPI can manage.

cutting speed = radius x RPM. Smaller your radius the more speed you need for stability.