# Thread: power of milling motor

1. ## power of milling motor

Hi all.

Like a lot of you here, I also want to build a milling machine. and what I think is as standart procedure is to start with some calculations. I did a few. and I was wondering what kind of motor powers you are using.

I calculated that a milling machine capabel of milling a stroke 5mm and 5mm deep in standart C45 steel with a fz of 0,2mm and a vc of 0,6m/s would need a motor with 3800W. could I calculated it correct???

and what kind of motor power are you all using.

Greetings Maarten.

P.s. if there are some mistakes in my english, don`t judge me.....

2. your saying you want to mill 5mm deep with a 5mm end mill in steel? Thats not too good of an idea unless its a rougher, and if it is, it doesnt take quite as much.
I dont know how big of a machine your looking to build, but now that I think about it, My machine only has a 450w motor on it, its a seige x2. I havent milled much steel on it though, you need to run it quite a bit slower than how I run it. The way I have my pully ratios wouldnt be good for milling steel.
I used a 3/8" rougher in some steel just surfacing some bar, I took about .05" wich is nothing at a decent speed, seemed to handle it alright.
But, of course, more power is better I do want to get a bigger motor some time or another.

Jon

3. yah... I just watch another time trouch my calculations, and I took a speed from 0,6m/s but this is much to high. so I turned it down to 0,01m/s and now I only need a power of 63W....

that sound a lot better

4. the rule of thumb is the diameter of the cutter is about the max depth of cut
A ripper cutter (the type with serrated edges will take more; I take 1" regular with a 3/4")
But the speed is important; most CNC operators use way too high of a spindle rpm
for a 1/4" 2 or 4 flute end mill I use 800 rpm and can take the full depth