milling a 2mm slot in mild steel

Hi All,

I want to mill the above along a 4mm section of steel. The smallest cutter I've used so far is a 3mm, but was hand fed for a very short distance at maximum rpm and I was sweating all the way through (didn't break the cutter though

The cutter I've got is HSS 2 flute and as I've got a powered x axis, will be using that. Can someone give me a little help on speed/feed/cut please? I've only got the one cutter but I'd like to preserve it as best I can.

My machine is a Warco VMC.

Thanks

Dave T

Edited By Dave T on 01/06/2018 23:12:05

1500rpm, 0.5mm depth of cut, 100mm/min feed.

Try it first hand feeding and if it is happy engage the feed

Thanks Jason

My milling chart says 2400 rpm for a 4mm cutter in mild steel. If you’ve got a VMC you should have a 2100 rpm option, that will do. I would sneak up on it and try a cut at 0.25mm first and increase slowly if it’s happy. 100mm/min feed is about right.

I have a spare 1/16" cutter ex cutting plastic on a CNC router, PM me if you are in need! I have found they may not cut plastics cleanly, but seem to cut metals OK

Vic,

It's a 2 mm slot in 4mm material

To avoid breaking your cutter, might a slitting saw be an alternative?

Ah, not sure of the speed then my chart doesn’t go that small. As said though, a slitting saw may be better?

A slitting saw is a definite thought, thanks

That's another reason I don't bother with charts - you are not stuffed if the size you want isn't on the chart. Anyway with no speed readout on my X3 it's all a bit finger in the wind

Thought I'd give it a go for you, used ketan's SX2.7 as that has a speed readout. Speeds and feeds as I said above but did not have a 2-flute so this is with a 3-flute, two you could up the speed and or lower the feed to keep a similar loading per tooth. Feed screw is 2mm pitch if you want to work out exact feed from my hand movements.

If your cutter is a 50p Bangood special then all bets are off.

Edited By JasonB on 02/06/2018 17:09:17

Thanks again Jason

Looking at the speed range on the VMC you’re be at it’s highest speed using a 2mm cutter and should get a nice finish.

Cheers Vic

Just so happened to use the 2mm cutter last night on some cast iron, similar sort of speed but 1.0mm DOC, feed a bit of an unknown as cuts were on the R/T. Deep pockets are 4mm.