15K Spindle Warmup Dilemma

[Dickie Frank]

I have a 2021 Haas VF-2SS with a 15K Spindle. A lot of our programs run between 10k-13k. Our warmup program ramps up to 15k over 20 minutes and traverses all the axis.

Questions:
- Can I stop at 13k in the warmup program since we never use the spindle at that higher speed?
- Are there pros/cons to running the spindle all the way up to 15k in the warmup program?
- Is ramping up to 15k unneccesary wear and tear on the spindle?
- Is it bad for the spindle if we never run it at top speed (required for proper lubrication or something)?

For context we use a lot of small tooling and used to run at 15k all the time but the spindle failed the day before the machine turned 2 years old. Haas warrantied the spindle, but I never found out what the issue was...I assume it was a bearing? Since then we've dialed back our spindle speeds out of fear of killing the new spindle.

Thanks in advance!

 

[Donkey Hotey]

Warm-up cycles have nothing to do with which RPM they get to and everything to do with giving everything a chance to smear the oil around and get the bearings up to some kind of operating temp before they see a load. You could probably argue that it's good enough after five minutes but, why rush it? Walk in, power up the machine, run the warm-up and then go do all your normal morning routine.

 

[Dickie Frank]

Okay cool. Thanks for the reply. So might as well just run it at 15k then. Just traumatized by the first spindle failing...want to make sure I'm nice to this one!

 

[Garwood]

My big Kitamura has 37,000 spindle run hours on a 10K Cat50 air/oil spindle. It was purchased new to hard mill 60RC toolsteel inserts on the face and sides. It did that until I bought it a few years ago. It still has the original spindle and I can have a conversation in a normal voice standing in front of the mill at 10K.

Kitamura has a rigid warmup policy. 30 minutes everyday, an hour on Monday and 4 hours if it sits more than a few days. I stick to that schedule and haven't had an issue.

10K Cat50 is about 5 times more mass than a 15K Cat40 spindle BTW.

 

[metal-ica]

Haas warrantied the spindle

How did you get them to warranty the spindle?

 

[boslab]

Got to wonder if it an oil lubed spindle if they are using the right oil, could be the warm up taking metal to metal before the oil gets there, usually there is a residual film, but I guess if the spindle is hot it’s dropping off the bearing surfaces? An oil sample to a good tribologist would confirm metal content and type, whilst the machine is “ rated” for high rpm doesn’t sound like they actually expect users to push rpm does it?
Does the oil pump fun before the spindle runs crossed the grey matter.
Mark

 

[GregSY]

I tend to doubt that 13K is gonna help much if 15K is causing an issue.

 

[friesen]

Rpm does matter imo, mainly that it’s not too high until the oil gets blown out, otherwise it seems like it could get pretty hot.

 

[friesen]

I don’t see much sense in running a 10k spindle at 10k as part of the warmup though.

 

[Garwood]

IMO, air oil most definitely requires a warmup and high spindle RPM is required, not optional, and doesn't damage them.

You should not need to "blow out" any oil in the spindle bearings. The amount of oil used is so small and precisely metered it should never be dripping out.

Air oil spindles are awesome for production where they run all the time. Not so great in shops where they sit alot and are used sporadically.

The manufacturer might have something to do with why the spindle died so young.

 

[friesen]

If my haas sits for a while and I do a warmup, the spindle definitely gets warmer than usual. It’s because oil collects or pools in the bearing area.

 

[Dickie Frank]

My big Kitamura has 37,000 spindle run hours on a 10K Cat50 air/oil spindle. It was purchased new to hard mill 60RC toolsteel inserts on the face and sides. It did that until I bought it a few years ago. It still has the original spindle and I can have a conversation in a normal voice standing in front of the mill at 10K.

Kitamura has a rigid warmup policy. 30 minutes everyday, an hour on Monday and 4 hours if it sits more than a few days. I stick to that schedule and haven't had an issue.

10K Cat50 is about 5 times more mass than a 15K Cat40 spindle BTW.

Sounds like a beast!

I’ve been diligent with the warmup routine. Haas recommends warming up the spindle if the machine has been idle for 4 days+ or if you are going to use it at high RPM right away. So I've always run it every morning.

 

[Dickie Frank]

How did you get them to warranty the spindle?

I had a 2 year warranty, which was a promotion they were offering when I bought the machine. Also, my HFO was awesome. They had a new spindle installed in 1 week and sent the seized spindle back for investigation. 2 months later I learned that they had determined it would be covered under warranty, which was a massive relief.

 

[Dickie Frank]

IMO, air oil most definitely requires a warmup and high spindle RPM is required, not optional, and doesn't damage them.

You should not need to "blow out" any oil in the spindle bearings. The amount of oil used is so small and precisely metered it should never be dripping out.

Air oil spindles are awesome for production where they run all the time. Not so great in shops where they sit alot and are used sporadically.

The manufacturer might have something to do with why the spindle died so young.

The haas drips 2-3 drops of oil every 20 minutes, which is slowly pumped through an airline into the spindle, so yea, it's not much oil. I don't use any coolant so I can see a very fine spattering of spindle oil on my parts and can often find a little oil on the spindle nose the next morning. The spindle has a air purge, which pushes out the oil.

I try to keep it running as much as I can, but it certainly will sit idle for 15-20 minutes here and there throughout the day, or longer if I'm pulled away to do something else. I don't run the warmup again if its idle for a few hours though...just first thing in the morning.

 

[usolutions]

I have similar warmup routine to Kitamura, 15k rpm bbt40 spindle, I put smart relay on daily timer circuit. When I'm off to the workshop, push of a button and machine starts to do its job, and it is nice and done by the time I arrive to the workshop. Does your haas has something like that?

 

[Dickie Frank]

I have similar warmup routine to Kitamura, 15k rpm bbt40 spindle, I put smart relay on daily timer circuit. When I'm off to the workshop, push of a button and machine starts to do its job, and it is nice and done by the time I arrive to the workshop. Does your haas has something like that?

That's awesome. I'd love to have that set up on my Haas. It powers the machine up and runs the warmup program?

 

[Dickie Frank]

I tend to doubt that 13K is gonna help much if 15K is causing an issue.

We're just choosing not to run it at high speed all day. We run some of the smaller tools at 13k, but mostly 10k now. Haas hasn't said that their spindles arent rated for continuous high speed operation, but I've heard that they will have a shorter life if they are. I've heard this of other machine tools as well. My thinking is lower spindle speed, longer spindle life

I hope that my last spindle failure was a fluke. It seized right in the middle of a typical program...no crash, bump, high load, or anything.

 

[rklopp]

My thinking is lower spindle speed, longer spindle life

Barring a crash or contamination, spindle life is based on the number of revolutions, which controls the number of fatigue cycles on the bearing races. If you lower the RPM, you have to lower the feed rate to keep the same chip thickness, so parts take longer to cut, but still require the same number of spindle rotations. For the most part, the spindle life in terms of the number of parts you get out of it does not significantly change if you lower the speed from 15k to 13k RPM. It's probably better to think in terms of the number of parts the spindle can make as opposed to how many hours it can rotate.

 

[empower]

RPM alone does NOT kill spindles. no lubrication or bad lubrication, bad balance etc PLUS rpm = dead spindle/bearings. if your lubrication/cooling is fine and your tool holders are good quality, not out of balance - there is zero reason to not run the rpm the spindle is built to run at.

 

[boosted]

This topic frequently gets beat to death.

I don’t understand why so many folks find it impossible to just look in the manual for their machine, and run the warmup procedure as specified by the manufacturer.

Not all spindles are the same, so there is no one-size-fits all warmup procedure.

I have four different mills in my shop, and they have four different warmup routines.

Warmup is only one of many factors that affect spindle life, and again, not all spindles have the same sensitivities.