[Aleksandar911]

Hello everyone, first of all a short introduction-my name is Aleksandar, and I'm here to help a friend of mine with a problem. He's not that good with English, and I know nothing about CNC machining, so I apologise in advance for newbie questions, hopefully you can help us out, he's been working with wood a lot but never with metal.


Anyway, the job at hand is cutting 2mm thick letters out of 80x20 aluminium plate. The router bit diameter shouldn't be over 2mm.

Basically, he'd like to know which router bit you would reccomend, which RPM he should use, which feed and plunge rate?



His CNC router is 1200x800x150. RPM is adjustable from 0-22000rpm.

[Algirdas]

chip thickness and feederate depends on cutter bit selected (with respect to RPM, of course). I would recommend Sandvik Coromant or Iscar.
Don't you think it's work for laser or punch machine?

[EPTech]

I recommend an uncoated polished hard metal cutter. ex. GARR TOOL. Cutting speeds and feed rates can be found on the same site. Speed should be round 20000 rpm, feed rate about 1200 mm/min, cut increment no more than 1mm. If you are cutting dry, use half that speed and feed rate?

[Aleksandar911]

Thank you guys!

We used those kind of values but the bit broke, maybe it was a low quality bit. WD 40 as lubricant/coolant. We'll try the Garr tools with those rpm, feed values, thanks again.

[EPTech]

Makes sense. WD-40 is a lubricate. It will only work for low speed cutting of ferrous materials, ex thread cutting. For high speed cutting you need a liquid that acts as a coolant and lubricate at the same time. The higher the speed, the more important the coolant factor. WD-40 will actually make the chips stick to the cutter when it burns instead of washing them away. I use Esprit 5000 from total as a general coolant/lubricate in my shop. But it is kind of expensive, worth its money though. Anyhow, if you do not want to spend lots of money on special fluids, I remember lamp petrol was also used in the days, but again at lower speeds. Not recommended, because it can ignite and cause fire. Use SMALL quantities.
In the end, just cut it dry and remove chips with compressed air. DO NOT use the WD-40.

[Aleksandar911]

Good to know, we'll look into it.

Anyhow, would you happen to know an online shop in Europe which sells Garr tools, I googled it but I usually find American websites. The distributors list on garr website is somewhat poor, and the companies listed either don't ship items or don't list a website.