[Dallas J]

I think the issue for me getting chatter with 1/2 end mills is stick out. The tool length fitting in an ER20 collet ends up giving about 1.5" of stickout and at around 2CIM, regardless of wide and slow and narrow and fast, is exceeding 0.001" deflection. It seems on this particular setup, that's just not tolerable.

Ive tried slower RPM, faster speed, tighter PDB (it barely comes out when released now), very tight or kinda tight collets... Gibs are tight and I don't get different chatter in X vs Y now that that's good. It really seems that 0.001" deflection is that configurations limit. A stubby would probably fix it all.

Oh, this is 2flute HSS. Perhaps 3flute or carbide would make things better too but for now I'm just using the long edge for cleanup after roughing everything out with the insert tool.

[SCzEngrgGroup]

I think the issue for me getting chatter with 1/2 end mills is stick out. The tool length fitting in an ER20 collet ends up giving about 1.5" of stickout and at around 2CIM, regardless of wide and slow and narrow and fast, is exceeding 0.001" deflection. It seems on this particular setup, that's just not tolerable.

Ive tried slower RPM, faster speed, tighter PDB (it barely comes out when released now), very tight or kinda tight collets... Gibs are tight and I don't get different chatter in X vs Y now that that's good. It really seems that 0.001" deflection is that configurations limit. A stubby would probably fix it all.

Oh, this is 2flute HSS. Perhaps 3flute or carbide would make things better too but for now I'm just using the long edge for cleanup after roughing everything out with the insert tool.

I work almost exclusively with HSS, and 1/2" 2-flutes are my preferred roughing tool. Most are in ER20 holders, with ~1.5" stick-out. My normal 6061 roughing cut (NOT maximum MRR) is 1/2" DOC, 0.05" WOC, 110 IPM. I can run close to 3/4" DOC, but that is close to the spindle power limit, so leaves no margin for error. I get zero chatter. Ever.

It would be interesting to try an experiment. Forego the PDB, and instead hand-tighten the drawbar to 25-30 ft-lbs, so the springs are completely compressed flat. I suspect you might get a very different result.

Regards,
Ray L.

[Dallas J]

I can certainly try it. I've also never tried running cuts that fast. I'll give that recipe a shot at .5" DOC and report back how it runs. Will also try cranking down PDB to see if any difference.

I do know that if I don't keep collet and tools clean I get pull out and then once pullout starts chatter gets worse. For instance, pushing the Shear hog when my insert got dull from a mistake would cause it to creep out. Wouldn't have any issue till it started pulling out. Cleaned up the shaft and collar and no more issue.

[SCzEngrgGroup]

I can certainly try it. I've also never tried running cuts that fast. I'll give that recipe a shot at .5" DOC and report back how it runs. Will also try cranking down PDB to see if any difference.

I do know that if I don't keep collet and tools clean I get pull out and then once pullout starts chatter gets worse. For instance, pushing the Shear hog when my insert got dull from a mistake would cause it to creep out. Wouldn't have any issue till it started pulling out. Cleaned up the shaft and collar and no more issue.

You won't get pull-out with adequate drawbar tension. I've never once gotten pull-out on my machine (using my own motor-driven PDB that torques the drawbar to 25-30 ft-lbs), even when I've screwed up the feeds and speeds to the point I got sustained chatter that was literally painful to listen to. Sadly, the Tormach PDB does not always provide adequate drawbar tension, but manually tightening to 25-30 ft-lbs will ensure the tool is tight, and it will NOT pull out under any circumstance at that tension. Trying that will tell you whether or not drawbar tension is, as I suspect, at least part of your problem.

Regards,
Ray L.

[luv2ride]

I was running .1 WOC with the 1/2" YG1 at .375 and getting chatter and pullout and the motor reached it's limits. I cleaned up the collet which helped a little bit. The solution was replacing the collet and WOC. I haven't tried a 1x DOC since.

[tbev]

Based on that vid that looks like you found a great end mill. Ive tried many 1/2"ers and i always have bad chatter almost no matter what settings. I'll have to try that guy out.

That looks great, forty bucks is pretty sweet too IMO. I have had the best experience with the coated carbide 2fl .5in from Tormach actually, that was a great cutter I think, I beat the he'll out of it and it always left a great finish. I think I'll try this one next.Thanks for the vid!

[CadRhino]

I use an atc and don't think it will function properly if I really crank down in the pdb torque. I only use up to 3/8" em due to pullout.

You won't get pull-out with adequate drawbar tension. I've never once gotten pull-out on my machine (using my own motor-driven PDB that torques the drawbar to 25-30 ft-lbs), even when I've screwed up the feeds and speeds to the point I got sustained chatter that was literally painful to listen to. Sadly, the Tormach PDB does not always provide adequate drawbar tension, but manually tightening to 25-30 ft-lbs will ensure the tool is tight, and it will NOT pull out under any circumstance at that tension. Trying that will tell you whether or not drawbar tension is, as I suspect, at least part of your problem.

Regards,
Ray L.

[sunvolt]

Here's a good source and very easy to find what you need fast:

End Mill Depot - End Mill Depot Home Page

Also, and this is very interesting, YG makes an end mill with the same helix angle and grind as the AluPower high performance tools but in HSS.
Way cheaper and they absolutely scoot: * SUPER HSS END MILLS FOR ALUMINUM *

[pickled]

Here's a good source and very easy to find what you need fast:

End Mill Depot - End Mill Depot Home Page

Also, and this is very interesting, YG makes an end mill with the same helix angle and grind as the AluPower high performance tools but in HSS.
Way cheaper and they absolutely scoot: * SUPER HSS END MILLS FOR ALUMINUM *

Thanks for sharing! Those are extremely affordable and would fit my needs for the small volume of aluminum work that I do here. Too cool!

[luv2ride]

Here's a good source and very easy to find what you need fast:

End Mill Depot - End Mill Depot Home Page

Also, and this is very interesting, YG makes an end mill with the same helix angle and grind as the AluPower high performance tools but in HSS.
Way cheaper and they absolutely scoot: * SUPER HSS END MILLS FOR ALUMINUM *

Those are the ones that I order. Amazon has them about the same price usually and I can get them in 2 days.

[dic_tools]

Hi

There are different types of endmills used in milling applications side milling, profiling, face milling. Corner Radius End Mills are suitable for the die and mold industry. corner radius end mills are different flutes and shank types. other than Sharp end mills have sharp teeth than the corner radius end mill.

DIC TOOLS INDIA

https://dictoolsindia.com/hss-cuttin...-end-mills.php