Taking A Poll: Speeds And Feeds

[HimyKabibble]

All,

I've spent countless hours finding as much information as I can, and being amazed at how little agreement there is, even across manufacturers. I see SFPM numbers from 200 to 600, chiploads from 0.001 to 0.006. I know my machine (a BP clone) is quite happy roughing with a 2-flute HSS endmill at 3200 RPM and 10-12 IPM with a 0.5" DOC and mist coolant. This gives me a good finish, long tool life, etc. But, calculations show I might potentially be able to run considerably faster than that (well, assuming enough spindle power). Would I be better off going to 1" DOC and 5 IPM? Or maybe 0.25" DOC and 25 IPM? Or faster? I haven't done a huge amount of experimentation (though I plan to over the next few days, so I expect to "sacrifice" a few tools to the Gods of CNC....).

I'm just curious what other people use. I understand there will be variation machine-to-machine, but I think it would be interesting to see what the spead is. So, suppose you want to rough out a 1" deep pocket in 6061, using 1/2" HSS tooling. What tool would you use (2-flute? 4-flute rougher?), at what RPM and what feed? Assume coolant.

Now, how about same question, but using a 1/4" tool instead? And 3/4" tool.

This should be interesting....

Regards,
Ray L.

[RMR]

1/2 3 flute Y/G alupower 55 ipm 7500 rpm 1/2 doc. 1/4 3 flute Y/G alupower 24 ipm at 7500 rpm .25 doc

[CarbideBob]

Originally Posted by RMR 1/2 3 flute Y/G alupower 55 ipm 7500 rpm 1/2 doc.

7500 rpm on a B-port clone?
That would be interesting to watch.
Bob

[HimyKabibble]

Originally Posted by RMR 1/2 3 flute Y/G alupower 55 ipm 7500 rpm 1/2 doc. 1/4 3 flute Y/G alupower 24 ipm at 7500 rpm .25 doc

The 7500 RPM really surprises me! That's over 900 SFPM. I see that's a "powder metal" tool, which I have no experience with. That's 0.001" chipload, which is surprisingly light, especially for a rougher. Are you limited by spindle power under those conditions? What kind of tool life do you get with that?

Regards,
Ray L.

[HimyKabibble]

Originally Posted by CarbideBob 7500 rpm on a B-port clone? That would be interesting to watch. Bob

I run my Taiwanese BP clone up to 8200 RPM (5440 RPM rated speed + VFD cranked up to 90Hz). It doesn't seem unhappy there. The spindle gets warm, not hot, after a couple of hours of continuous running.

Regards,
Ray L.

[RMR]

I have a HAAS VF1 and an HL10, I can get away with 100 ipm on the 1/2 Y/G but with only .25 doc because of HP at that rpm . The 1/4 Y/G I have gone as high as 40 ipm. Those other #'s were safe # to last forever.

[HimyKabibble]

Originally Posted by RMR I have a HAAS VF1 and an HL10, I can get away with 100 ipm on the 1/2 Y/G but with only .25 doc because of HP at that rpm . The 1/4 Y/G I have gone as high as 40 ipm. Those other #'s were safe # to last forever.

Very impressive! Care to hazard a guess what you could get away with using standard HSS 2-flutes?

Regards,
Ray L.

[RMR]

I don't buy HSS end mills because I can buy the Y/G's for such a good price I don't even mess with regrind. The 1/2 Y/G is around $26 to $30 and if you take care of them you will make good money with them.

[HimyKabibble]

Originally Posted by RMR I don't buy HSS end mills because I can buy the Y/G's for such a good price I don't even mess with regrind. The 1/2 Y/G is around $26 to $30 and if you take care of them you will make good money with them.

Wow! Where do you get them for that price? The places I've seen they were twice that.

Regards,
Ray L.

[HimyKabibble]

Come on, guys! I know there's more than two of us cutting aluminum! Let's have some more feedback.

I just spent some time playing, and testing different feed rates. Here's what I found (all in 6061, using heavy mist coolant) the limits to be, before clogging or other bad things happen:

1/2" HSS 2-flute - ~15IPM for deep slotting (1/2" DOC) at 2500 RPM. So, my 10-12IPM typical rate seems about right.

1/2" HSS 2-flute - ~25IPM for shallow slotting (1/4" DOC) at 2500 RPM.

1/2" HSS 4-flute rougher - ~20IPM for deep slotting (1/2" DOC) at 2500 RPM.

Pretty darned amazing how far a 1/2" endmill will bend when it clogs and stops turning during a fast feed!

I gotta find me some of them YG1 "Speed Freeks"....

Regards,
Ray L.

[RMR]

I buy most of my tooling at Triad Tools in Colorado, I think the city is Arvada.
303-424-3006 Don't quote me on tooling because it has been about three months since I bought 1/2 inch end mills.

[RMR]

Remember that the speeds and feeds I talked about are with flood coolant not spray mist.