Warm up for a 12000 RPM spindle?

On the side of this new to me VMC it has a warm up procedure that reads as follows. It seems a little extreme to me the 24000 RPM spindle on my router warms up for 15 minutes. This thing is about 2 hours if it hasn't run for a couple weeks according to this sticker on the side of the machine does this sound normal? Machine is a Sharp SVL-2416SE-M 12000 RPM.

I would be guessing that router spindle won't cost a fortune to repair if it fails. I would just go with the manufacturer's recommendation and not risk it as the spindle should not be off for two weeks very often

That is not a "warm up" procedure gundog. That is a "run in" procedure. For a new spindle.

Here is what an old-timer HAAS tech told me about spindle care on HAAS 12k spindles:
Fire it up in the morning, and let it run at 1500rpm for about 15 minutes. Then let'er eat!
Now, HAAS uses ceramic bearings, and air/oil mist to lube the bearings.
He said what happens is, oil puddles in the bottom bearing over night, and if you whack the throttle wide open first thing in the morning?
That bottom bearing gets super hot, super fast. It needs the air to cool. And when submerged the air cant flow.

Its been working for me for 8 years (knock on wood!).
Even the spindle that got crashed 4 years ago that I didn't think would make it another month:
(the crash changed the pitch (sound) of the spindle and made it much louder) Is still going!
And, all my spindles pretty much live at 12k all day long.

Now, having said all that, I have no idea what kind of bearings your Sharp uses, or how they are lubed.

wheelieking71 said:

That is not a "warm up" procedure gundog. That is a "run in" procedure. For a new spindle.

Here is what an old-timer HAAS tech told me about spindle care on HAAS 12k spindles:
Fire it up in the morning, and let it run at 1500rpm for about 15 minutes. Then let'er eat!
Now, HAAS uses ceramic bearings, and air/oil mist to lube the bearings.
He said what happens is, oil puddles in the bottom bearing over night, and if you whack the throttle wide open first thing in the morning?
That bottom bearing gets super hot, super fast. It needs the air to cool. And when submerged the air cant flow.

Its been working for me for 8 years (knock on wood!).
Even the spindle that got crashed 4 years ago that I didn't think would make it another month:
(the crash changed the pitch (sound) of the spindle and made it much louder) Is still going!
And, all my spindles pretty much live at 12k all day long.

Now, having said all that, I have no idea what kind of bearings your Sharp uses, or how they are lubed.

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It does say run in procedure. But what gets me is it says if it has sat for 72 hrs one procedure and 2 weeks or more for another. I will have it sit for weeks at times I am just wondering if I need to write a program for this? I am warming it up now to run a test part first in air and if it looks good I am going to do some drilling.

Dualkit said:

I would be guessing that router spindle won't cost a fortune to repair if it fails. I would just go with the manufacturer's recommendation and not risk it as the spindle should not be off for two weeks very often

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Router spindle is $8800 so it isn't cheap either.

I would have to ask.. What are you actually doing when you are "Warming up the spindle"??

As far as I've figured out, you are taking any grease or oil that has settled and redistributing
it through out the bearings before you let it rip or put a load on it.

If it takes over a half million revolutions to do that, I think there is a problem.

Router spindle is $8800 so it isn't cheap either.

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I was going to say the same thing. 10hp ATC router spindles are more expensive than a Haas spindle for example.

To the OP. You might as well just call the manufacture to be because it did say over 2 weeks. The warm up program that comes with Haas machines runs for 20 mins at increasing RPM stages. The run in program is over an hour. I always use the warm up program if the machines been idle for more than 4 hours. I would whatever they recommend.

On my 15k spindle in my Haas, I *always* run it for maybe 5 minutes at ~1000rpm when it's cold. If I'm not going to run a tool any faster than 3k or so, I might run it for a five minutes at 2500-3000, then I feel I'm good to go.

If I am going to run something in the 10k-15k range, I have a routine that bumps up at 2k at a time for a couple of minutes each. I honestly don't think it matters as far as the spindle lube (per what wheelieking said), but the spindle creeps a bit as it gets warm, so I'll usually get the spindle up to that higher rpm temp before I set the tool lengths and do the final Z probe. (assuming it's a part where I'm really trying to hold tolerance close). Typically I'll check the spindle temp housing with an IR gun, because I know about where it "settles in" when it's fully warmed up.

fwiw...

PM

We had a call into Sharp when I posted this but they had not called back they finally called back and the guy said to do what the sticker says he also told me not to run my 12000 RPM spindle any higher than 10000 RPM or it won't last long that kinda sucks but I will take his advise.

My son was helping me get this thing figured out he is much smarter than the old man we programmed a test part and ran an air cut it looked ok so we ran a part and it all worked great. I was a simple part with about 17 drilled holes using 3 tools. After running that bed mill making these parts man is this thing nice and I did not have to sweep the floor and the part was done in a little over a minute.

Other than the stated lubrication issues mentioned. Which are minor unless it has been sitting for a long time, the main reason to warm up a spindle is typically to achieve the proper preload on the bearings. This gets more and more true on faster spindles. Say 15k+. For an 8000 rpm spindle, I would never worry about it. For a 12k spindle, I wouldn't worry about it unless you go dead cold (for a month) to 12k and start loading the crap out of it right out of the gate.

I challenge anyone here to provide any real evidence of premature spindle failure from not warming up their spindle properly every day. I have been in too many shops that just let them rip right out of the gate and I have never seen one go bad. Some of these machines are 24k spindles and go right to 18k with 70-80% spindle load within 10 seconds of the start of the program. These spindles have roughly six thousand hours on them and are still in great shape minus a few bumps. Mind you they are also water cooled and are permanently lubricated bearings. The manual only states that warmup is required for proper preload. If you don't exceed the preload generated when cold, you won't have a problem.

Mind you running in a new spindle or one that has sat for a long time is an entirely different story.

If you are that paranoid about it, write a timer macro and tie it to an mcode. It would warm up the spindle if the machine hasn't ran in a while, then call said mcode at the end of the program again to save the last cycle ran so when you hit the button the next time it won't have to warm up. If you wanted to get fancy you could probably make it part of the M3 macro. Just be sure you have a tool in the spindle that can handle the rpm you want to warm up with.

Husker

10K on my Mazak VTC 300. And hitting the green button for 10k when cold made me hit the red button because of the noise. Not a good noise. 10 min at 1k and all was fine.

gundog said:

we had a call into sharp when i posted this but they had not called back they finally called back and the guy said to do what the sticker says he also told me not to run my 12000 rpm spindle any higher than 10000 rpm or it won't last long that kinda sucks but i will take his advise.

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!! Bullcrap !!

What I noticed is my machine is a 2014 and seems to be the same as the new 2018 model but they are now only rated @ 10,000 RPM the rep told me they had a lot of them fail being ran at 12,000 RPM I am guessing they down rated the spindle for that reason. The other thing I noticed is mine has a 20 place ATC umbrella type but the new ones have a 16 place ATC umbrella and the 20 place upgrade now is a side loader.

I think sharp is a grease spindle and from what I have seen most grease spindles over 10K do not live a long happy life.. The 30 taper guys get away with it do to a lot smaller bearings .

I run my Haas spindles at 12K all day long and they never get warm.. but my grease fadal spindle gets warm at 6K after a few hours. I think wheelie is spot on about the air cooling the bearings.

gundog does you machine have a built by sharp or Built by First tag? Around 2014 was when sharp quit selling machines made by first and starting building there own copy of the First machines.... At that point first starting selling under Acer, kent , Webb and a ton of other names ...

D.D.Machine said:

I think sharp is a grease spindle and from what I have seen most grease spindles over 10K do not live a long happy life..

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Makino 20k Cat40 HMC spindles are grease lubed. IME, they are good for ~10 years at a couple shifts a day. Seems a reasonably long and happy life to me.

D.D.Machine said:

gundog does you machine have a built by sharp or Built by First tag? Around 2014 was when sharp quit selling machines made by first and starting building there own copy of the First machines.... At that point first starting selling under Acer, kent , Webb and a ton of other names ...

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I think it is built by Sharp but I am not sure I will look tomorrow. The spindle does have a chiller I am not really sure how that works.

Grease DOES have the disadvantage regarding speed vs heat. That is a fact. But if you can manage the heat, there are perks to grease like having a more sealed environment and not being subject to other concerns like air or lube quality. Grease spindle warm up is more critical.

Makino and other high end MTBs will have a proper spindler chiller, NOT the poor mans way like Haas which is to run coolant through a jacket in the spindle. Its better than nothing but a fair bet that if your spindle taper is getting warm, your bearings are much hotter and probably seeing Z length changes in parts and tool sticking.

We just turn spindles on a lower rpm for a while. Haven't lost one yet.

I would be highly annoyed with a MTB that marketed their machine with 12k rpm, but probably knowing that was really pushing it and the machine could not handle that speed for very long. They either don't have their design in check or they don't have proper cooling. Depending on how they designed it, the heat could cause more preload in the bearings which just brings more heat...right to the end. Feel the taper, it will tell you what you need to do.

My simple rule is to jog up to half speed once or twice before running fult tilt for a same week start..for a month or so hand turn or jog to 1/4 speed a few times (4+) will/may make a spindle last twice as long.

The "warm up" cycle on the Hermle's 25k spindle seems strange to me until I asked the theory behind it. Similar to Wheelieking's input. The German guys have it run at 200 rpm's for like 2 minutes, then it blasts up to 21k for around 5 minutes. The theory is more related to lubrication, than warmup. They say the oil pools at the spindle nose, so spin it slow to displace some of it and get the new lube in there, then really let it rip to push it out. I would think more of a gradual warmup would be easier on the spindle but what do I know.