Good facing options for PCNC 440 in high belt?

Hi folks,
I am looking to add tooling to my 440 and some kind of facing tool would be useful. So far I have just been using a flat bottom 3/8” endmill. Most of my work is in aluminum but steel is also something I want to run more. I see a lot of discussion about the “Super Fly” but worry about the flatness of the surface with a mill not perfectly trammed. I also am concerned about the balance issue at higher RPM. Will a mini-sheer hog (3/4”) leave a good surface finish when used as a facing endmill? About 3/4” sounds pretty large to me in the small machine. I appreciate if you can share some experience and insight. Direct TTS or threaded adapter type? Thanks, Rick

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I have achieved the best surface finish with 2 inch 4 flute sandvik 490 shell mill with only one insert in it. Much better finish than the 3/4, 1, & 1 1/4 fly cutter set I purchased. I’ve tried small TNMG turning tools and hand ground tool steel in the fly cutter. If I run more inserts in the shell mill I can actually stall the spindle.

I have ordered a Tormach “super Fly” after all. The one thing I feel like I need is to provide a consistent looking surface finish on flat sides of some parts and most of my material removal needs seem pretty well accommodated by standard and roughing endmills in the 1/4” and 3/8” sizes. I haven’t tried a 1/2” endmill but for light cuts in pocket bottoms and such I expect they would work. Maybe a mini- shear will be in my future as I think the high-positive and polished inserts would be good on aluminum. Those inserts are expensive. I looked into alternatives and for the cost difference I’d just go Tormach as it is more proven. I tried to call up there to ask a few questions but with no luck.

It looks like my email got lost in the either somewhere, but in case anyone else stumbles into this thread at some point, here is what I know about facing tools that we offer.

The SuperFly is a common go-to facing mill for steel and aluminum. I like the finish it offers but the unbalanced nature of the tool causes the insert to wear out faster than other tools.

Most people that tire of wearing out inserts on the SuperFly go with a standard facing mill and just pull all but one insert out. The 38mm face mill is a good option for this since we have aluminum and steel inserts for it. Keep in mind that you won’t be plowing through material with this giant cutter on your 440, you will just be doing skim cuts to get the surface clean. You will need the TTS face mill arbor for this tool as well.

I like the whole shear hog and mini shear lineup for AL roughing but it doesn’t support steel inserts. If you go that route then the 1" mini-shear or the 2" face mill would be good options and you should go with an insert that has a bigger radius to minimize tool marks. We have R0.060" inserts for the Shear-Hog and R0.040" inserts for the Mini-Shear.

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I have a 770 rather than 440 but will mostly echo what others have said.
I used my SuperFly until I was using it manually and managed to start the spindle at 10000rpm. Seriously out of balance and never again. Good price to anyone in Canada who wants an almost new SuperFly.

I have cheap Chinese 4-insert face mills (50 and 63mm) that take the same SEHT inserts as the SuperFly. Using only one insert gives a great surface and almost no vibration due to the weight of the head relative to the missing insert.

For smaller facing jobs and waste stock removal I use a 3/4-inch ShearHog. Good bottom finish and good removal rate.

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Ken, that is very helpful also, thanks! I should have ordered the shear hog. That face finish on aluminum is what I’m after and the ability to remove a bit more material would be great. My gut told me the fly cutter would have balance issues. I have been impatient due to a job I am running which I want two well finished surfaces. I should have bought a 770 also. My space constraints put me in the 440 but now that I see how it is goes, the 770 could have just made it in there by letting the wire management caterpillar go between the steel trusses.
Regards,
Rick

Note that vertical wall finish is not great with a ShearHog. I usually leave 0.01 or so and take a full depth cleanup pass with a 1/4-inch 3-flute followed by a 90-degree chamfer cutter on the top edge. That way I get a mirror finish on top and side and without a sharp top edge. With a final pass DoC of perhaps 0.002 the Chinese, single SEHT insert, facemill gives a mirror finish across my 50/63mm wide piece. SEHT inserts are much cheaper than the ShearHog ones plus they are available for stuff harder than aluminum or plastic.

I would post photos but they lighting differences make them mostly useless to see the actual finish quality.

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Has anyone used the tts face mill arbor on a facemill other than the tormach ones? I ordered one of these (link below). It would be nice to use this with it.

I’ve modified arbors like C3/4 FMB22 Holder Face Mill Cutter 400R-50-22 +10Pcs APMT1604 Carbide Insert SET | eBay with my lathe to add a TTS groove to the shaft end. Works a treat!

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