[AMCTony]

Hi All,

I need a sanity check. I have a 2018 DT-2 Mill with a 20,000 RPM Spindle. We use it mostly for endmills and drills under 0.125" in aluminum. Tolerances are not too tight on the parts either. There is one operation that we did that required a 0.375" 3 flute endmill with a 37 deg. helix. The cut parameters are 13,250 RPM at 180 IPM. Ap is 0.800" and Ae is 0.056". The operation is milling a hole thru the part with an adaptive stratagy. A starter hole is already drilled in the center. Material is 7075 T6 Aluminum. The issue I am having is really nasty fretting on the tool tapers. I checked the pull studs, pull stud torque, Tool runout, and changed to a different holder. Results were the same. I decided to check the taper with some Dykem Hi-Spot blue and I really think that this machine has the taper ground like crap. This is a brand new machine and there are 46 hours on this spindle. I know im a bit heavy with my blue but the results are pretty clear in my mind. At least I think. I contacted my HFO and they think that I am being too aggressive with a BT30 Machine. I call BS. I know 30 taper machines are light but this is not a heavy cut. I have seen people take similar cuts on even lighter machines.

Any advice on this would be appreciated.

Attachment 409904Attachment 409906Attachment 409908

[erikfriesen]

Have you showed HAAS the blued taper? It really is going to wallow around bring so tight at the top.

[Superman]

You 1st have to verify that the holder taper is spot on before you you can say the other is crap.

Interpolating a hole feedrates can be deceptive.... your programmed feedrate is on the tool centerline...on the perimiter, it is actually faster.
Another thought... edge frittering can be caused by swarf re-cutting. Are you making sure the swarf is getting out ?

[AMCTony]

We blued up about a half a dozen holders. All with the same result. Also, the holders we blued were different brand holders as well. I didnt want to take a chance with a bad batch from one supplier. Swarf is no issue and we have little to no re cutting. I understand the issue with interpolation. I have run tools like this much much harder. We checked tool runout to verify that it was not causing issues. Also, the bottom of the pockets are 0.002 to 0.003 larger than the top. This is with the tool runout dialed in to 0.0001 TIR. That is way out of normal. All of our tool holders are showing a polish near the pull stud. One of the reasons I started to check with blue. I did send this off to Haas but they are kicking it around and I think no one wants to take responsibility with this. This particular machine has had its history of down time. I have had about 5 warrenty service calls on it already with issues spanning from way cover wipers that were 1/4" from touching the slide on the sides while overcompressed in the middle, (came like that from the factory), to bad prox switches to software issued that almost caused crashes if not for the operator hitting e stop. It took a week to fix the bad prox because this is a new version of the machine and haas didnt properly document what parameter went with what. It took the factory 3 days to figure it out with the service tech on the phone with them. This machine does this fretting with 0.25" endmills cutting at 20,000 rpm, 0.08" doc, 0.003" IPT and and Ae of 0.190". Takes longer for the fretting to show but still. I could continue.

[Jim Dawson]

Sounds like a heart to heart chat with Haas sales might be in order. Sounds like you got the ''Friday afternoon built machine''.

[AMCTony]

Sounds like a heart to heart chat with Haas sales might be in order. Sounds like you got the ''Friday afternoon built machine''.

My HFO seems to be pretty decent overall. I certainly will not let this go. My facility has 4 Haas machines and 3 run great. I really like the DT but this is bull. I do feel confident that has will resolve this. Heck, they have demos from trade shows where they are pushing the machine many times harder. Any service tech should be able to come to my facility and see there is an issue pretty fast. As far as the "Friday afternoon built machine" thing. I think so and I will add to it that I think Haas may have lowered their hiring standards for labor to meet demand and lower lead times. They have also been doing some things that are obviously for cost saving and its resulting in low quality. For example, the monitor is no where near as sharp and crisp as the VM3 we purchased 2 years earlier. The control pendant front panel was changed from a nice ground stainless steel to matte anodized aluminum and even made thinner resulting in a flimsy panel with the keypad buttons ready to fall out. The water separator just blew up one day. When we looked at it, the drain pipe leading out of the air panel was not lined up with the hole in the sheet metal. This combined with the fact that they went from an aluminum unit to a polycarbonate bowl that is now placed under stess and you can figure it out. They slowed the tool changer arm down from the older DT models for some reason. This disappointed me quite a bit. It probably doesn't matter all that much and maybe there was a good reason for it but hell if I can figure that out. I hope that they figure this out before I need to add another DT later this year. If not, then maybe its Robodrill time.

[Jim Dawson]

I have been very happy with my 2016 TM-2P. It has been good to us so far. The only problem so far was the tool changer lateral drive, sticky brushes in the motor.

Sounds like Haas has embarked on a cost reduction program, maybe to their detriment. There was another thread on a spindle problem with a bit older, but very low time machine, <200 spindle hours. It seemed that there was a problem from the factory but since it was out of warranty Haas would not even discuss some relief for the owner. All of this taken together is some concern for me.

[Ydna]

I'll say this, overtightening the pullstud is a common thing, but the blue'd pattern is usually higher up when that is the cause. (I don't doubt that you're using the proper torque for it)

With our DT machines, I find getting chips on the taper is a common thing, so we're meticulous about keeping the spindle clean. However there's usually small witness marks on the taper from chips, not a contiguous ring all around the taper like in your picture.

[engnerdan]

I have a 10/2018 built DT-2 with a 10K spindle. So far I have not seen any problems like you are having. I did have a TSC union that was squealing so bad my wife (in the house) asked me to shut it off. That was resolved by bumping the union with a deadblow so it was more centered on the motor shaft extension. I have got a little fretting with one tool that I know I am pushing my luck with. Its a 5/8" long flute 3 flute carbide with 3.25" of stick out (in 6061). I was using it in the shortest gage length end mill holder from Maritool and it was fretting at the drive slots. This tool is run at 0.600DOC, 0.10 WOC, 100 IPM and 10,000 RPM for 1.5 hours per part. I just switched to the next longer gage length holder last night and forgot to check to see if there is any fretting, if there is any I will have to slow it down. The fretting I had was nothing like what your picture shows. It was a 0.050-0.075" band right above the drive slots.



Non of the aluminum welded to the holder or tool is from running in the DT2, that was from a oops almost 2 years ago,


I run my 1/2" tool harder than your 3/8" with no problems in 6061, 0.600 DOC, 0.10 WOC 150-200 IPM and 10,000 RPM. No fretting just a rooster tail of chips.

I have also been running this, spindle killer according to some people, without any noticeable fretting. It only does very small light cuts surfacing deep inside a part.
Attachment 409980


I think there is something up with your taper and I agree Haas has been cheaping out their machines and it's a big disappointment. They can't even include two tee nuts, two bolts and two washers with a 4th or 5th axis rotary to secure it to the table. I bought a $25,000 TRT100 at work and a $10,500 HRT160SS for home and neither came with the $4 in hardware to secure it to the table.

-Dan

[AMCTony]

My HFO is sending out a tech to look at it. They seem to be in agreement that something is not right here. I will update when I hear more.

[AMCTony]

UPDATE

Haas replaced the spindle. The Haas tech agreed that the taper was messed up. You could take a toolholder with no pull stud in it, put it in the taper, and feel "shake" pushing back and fourth. Maybe about a thou or so but easily seen, heard, and felt. The new spindle showed none of that.

Blue results are also very clear...
Accupro Holder in old spindle
Attachment 410892


Accupro Holder in new spindle
Attachment 410894

I also did another brand of holder as well

Parlec Holder in old spindle
Attachment 410896

Parlec Holder in new spindle
Attachment 410898

I tested all the holders that I have and the results were consistent.

3 of my holders were trashed from Fretting damage which has me quite pissed.

So far, we have about 12 cutting hours on the spindle and the new tool holders are showing proper wear patterns evenly on the taper with no fretting. We have only run tools up to 0.250" 3 flute but these same holders were showing fretting in the old spindle. I am curious to see the results with larger tools.