Facing mill for PM30mv

[Pescadora]

I've been out of the game for a number of years (more than ten) and what I used to know is kind of sketchy these days. Acquired a PM30mv and a PM1030v last October and am still tooling up both machines as jobs require. On the list coming up is a facing job. Could do this on either machine even though it's starting with a square plate of A36. I like working with a mill better than with a lathe so started looking at face mill tooling. One such (possible) piece is the Grizzly G2861. 2.5 inch. Seems to me our mill should have enough HP to turn that, but there are some question marks.

I'm starting with .625 thick plate that I'll square up and remove the mill scale on both sides by taking it down to .500 with the face mill. This is where I run into trouble. The old tools and machine handbook lead me to a SFM of 100-125 for this material and with that tool diameter an RPM of around 250-300. But then there are YouTube videos with facing tools turning more like 1020 rpm and taking .040-.050 ADC with 70% RDC on 1018. Granted the tool was 1.5 instead of 2.5. But still, that's a pretty big difference.

So I'm thinking my old thinking must be off base. (4xSFM/tool diameter). The inserts are carbide. Does that give a 2.5-3X speed jump? Or what? Any help would be gratefully received.

 

[T Bredehoft]

I applaud your choice of machiery, I have the 1030 lathe and a PM25 mill.
I'd hesitate to hog with the mill, not sure about the capability of the PM30. I was cutting the other day in aluminum with a 1 1/2 facemill, .040 deep, but I'm not at all sure I could do that in steel. It's just a matter of chip load, if you feed too slowly it won't cut right, too fast will stall the tool. Yes, a Bridgeport or Kearney Trecker mill will handle that RPM And Feed, not sure about PM30. I would think taking .030 off of one side then the other, until you get to .500, would be good. Don't take it all at once, warping is almost guaranteed. Maybe finish with a .005 cut on each side.

 

[Pescadora]

I'm with you on that. The machine in the video was a Tormach 1100, which has similar spindle power (2hp). Here's the video:

It was impressive, especially depth of cut with those feed rates. NEVER having used a face mill, I'm all for being cautious.

Ever heard of Gwizard? I went to their site, but they seem just a bit too aggressive to get a subscription commitment for me.

To set up as shown in the video is about $300.00. https://www.tormach.com/store/index.php?app=ecom&ns=prodshow&ref=31280&portrelay=1