Spindle Speed Question

wawoodman

wawoodman

himself, himself
H-M Supporter Gold Member
Joined
Mar 19, 2011
Messages
940
A reference chart that I found online said for a 2" diameter cutter, on mild steel, ~200 rpm. I'm using a 2" face mill, with 3 inserts. It looks awfully slow to me. Did I miss something?

Even with a hand fed speed of dead slow, I'm not getting a really good finish. I can see the swirls.

And while I'm on the subject: I understand "roughing cut, conventional; finish cut, climb." So how does that work with a face mill? Should the work (1/2 inch wide) be run down the middle of the mill, or off to one side of the center?
 
For carbide inserts you roughly double the rpm.
As for feeding power feed gives a much better finish. If you have it.
With a face mill you will always see swirls they should be very fine . But you shouldn't feel them.
A picture would help us see if and what problems you are having.
 
Thanks. I'll post a pic tomorrow. Right now, I'm fuming because I screwed up a part I'm working on.

Unfortunately, the power feed is an armstrong.

<grumble, grumble>
 
Your spindle center line should be offset from the work center line in such a way that the very tip of the insert is not the first contact, but a little behind the tip, on the flank. This reduces the shock load and hammer on the inserts and they will last longer.

That chart sound more like it is for HSS end Mills. Sounds a little slow to me.
 
Carbide is meant for speed. Faster RPM's and heavy feeds. The inserts I've used were meant for powerful lathes with strong power feeds.

When possible I preferred cemented carbide so I could grind sharp cutting edges. I like using them on most standard lathes.
 
I would run the part a bit offset, maybe center of spindle to one edge of the part. If running left to right, set it to the 'back' side. Center line is ok, though. I would run a 2" inserted cutter at around 1000-1250 RPM. Type of material will determine how fast to feed, depth of cut, etc., and the type of finish you want. Slower feed will give better finish. Use some lubricant.
 
You must log in or register to reply here.
Back
Top