Carbide Inserts - Face Mill Cutter

[18w]

I won't offer up anything useful regarding face mills other than to say if you are only taking .020" passes on aluminum with a 3/4 endmill you aren't even beginning to use the capacity of your mill. Even a small mill should be able to take much deeper cuts. Fly cutters are excellent for finish and larger widths of cut. Some face mills perform the same task while others can also hog material as well as finish but a large dia. face mill requires some h.p. to take deeper cuts. If you just want to remove more material, look in to a 3/4" or 1" hss rougher end mill and experiment with your machine as to how hard you can push it. Lots of folks have face mills, as do I, but insert tooling that requires multiple inserts can use up a tooling budget really fast and if you aren't using it to its full potential, ie. faster feeds and doc, may not be the best choice. IMHO, your mileage may vary.

Darrell

 

[Franko]

Thanks Darrell.
I recently adjusted the ways to tighten things on that mill so I think everything is tight enough, but I felt like I was pushing as much cut as I could. Any deeper and the mill was starting to shake, especially as the bit crossed over the edge at the end of the pass. I was running the .75" end mill at about 1000 rpm. It is possible I don't have the column ways as tight as they could be. I'll look into that.

One problem I've seen taking deep cuts on aluminum is the cutting edge tends to gum up.

In my perusing face mills, I noticed some one to two inch carbide insert end mills that look like they may be good for removing more material. They use more standard inserts and cost significantly less than the face mills I've seen. MCSC had a 1" one set of 3 they called "The Little Hogger." It looks like they use fairly standard inserts, round, 3-sided and square.

 

[Ken_Shea]

Franko,
1000 is too slow, you should be able to run that 3/4" at 3000rpm if you have that available, that should smooth things up and also allow you to take a deeper cut.

I've never used it but others say WD-40 makes great lubricant for aluminum.
Soft aluminum can be real gummy to machine and lead to that build up you mentioned, WD-40 should help there.

3/4" and .020 as 18w pointed out is not optimum by any means.


Ken

 

[Franko]

I will give that a try, Ken. Thanks. I think 1750 is its top speed.

 

[kwilliam]

Also remember with 4 cutting edges you need 4 times the HP.

I have found even the plain triangular inserts give a great finish on Aluminium - as long as the have the "wiper"

The plain triangular inserts are also very robust

 

[18w]

+1 on what Ken said.Put it in top speed, spray with wd40 and let her rip. At 1750 rpm with a .750 endmill, that is about 343 sfm. Auminum cutting rates call for about 300 to 600 sfm in hss. Also in aluminum using a hss end mill 2 flute doesn't load up like a 4 flute will. Play with the feed rate also.

Darrell

 

[Ken_Shea]

Back to that Face mill, you won't regret having it if you decide to get one, run a 2" at your full RPM also in any aluminum and around 700rpm in mild steel, I've been kicking around getting a larger one myself as well.

 

[Ken_Shea]

Also remember with 4 cutting edges you need 4 times the HP.

kwilliam,
That's a new one to me and does not bear out in checking required HP in relation to flute count, some increase but it's very minor, almost moot.

 

[18w]

Also remember with 4 cutting edges you need 4 times the HP.

I have found even the plain triangular inserts give a great finish on Aluminium - as long as the have the "wiper"

The plain triangular inserts are also very robust

kwilliam,
That's a new one to me and does not bear out in checking required HP in relation to flute count, some increase but it's very minor, almost moot.

Ken is correct, facemill geometry governs hp requirements more so than number of inserts. http://www.glacern.com/fm45 shows a face mill with low hp requirements. It is all in how thin a chip is formed at the insert that makes some face mills more suitable. Yes there is some increase in hp requirements involving chip load, feed, rpm and number of inserts. If it took four times the hp even my Bridgeport would be inadequate and it does just fine with multiple insert mills but I am running a Glacern like the link I provided.

Darrell

 

[Bill C.]

Thanks, Ken. Sharper finer edge. That makes sense.

What I was hoping is that a face mill cutter is a better tool for hogging off a lot of material and would be capable of taking deeper cuts than a fly cutter whacking on the edges of the part.

Face endmills can really hog off the metal. I used them on a horizontal milling machine to square up plate stock. They do a quick job.