Morning Warm-Ups?

[GM81]

I was ridiculed the other morning for warming up the spindle before I started running. I was told I was just wasting 10 min and that the machine didn't need it.

I am a firm believer in warm ups.

How about you?

[Neal]

Running any machine with cold bearings in NOT a good idea. Running for a few minutes, like 10 or 15, allows the bearings to expand and take up the excess radial and axiel play in them.
When you run the warm up program you are extending the life of your spindle bearings AND distributing the way lube oil around the machine while heating up the ways. This reduces the inital themal expansion affect dramatically.
If you do not run a warm up, start now! (IMHO for what its worth)

Neal

[toddcheck]

Is there a warm up program in the mid 90's era controllers?

[Geof]

I have numerous machines and they all get warmed up every morning. On the 6000 rpm spindles it is maybe not necessary but for the 10000 rpm machines if you bang them up to full speed you are likely to get hot spindle bearings. If they have not been run for a week or so it is almost certain you will get very hot bearings, or worse, if you run them up to full speed immediately. The explanation I got for the reason warm up is needed is that the oil collects in the lower bearing and the warm up is needed to purge away excess oil; the heating comes from over-lubrication and the churning of the oil.

I also have a lathe with a grease lubricated spindle and if that is not run up to maxiomum speed in gradual steps it is very noisy. The warm up in this case re-distributes the grease that has settled to the bottom of a warm bearing.

If your machine has a maximum speed of less than 5000 rpm I think it is not really necessary to run a warm up for purging the bearings but certainly a warm up gets everything up closer to operating temperature so you are less likely to get sizes drifting due to temperature changes.

[fizzissist]

I have always warmed up my spindles with around 15 minutes at 2000rpm. It may not mean much, but as Neal points out, any lube that has settled gets redistributed, a little bit of thermal expansion means less impact damage, and I've found on my Fadal that as the machine warms up I'll get a slight change in my Z cuts.

Warming up the machine is also a great excuse to have some coffee and organize the work area.

[SBC Cycle]

Originally Posted by fizzissist Warming up the machine is also a great excuse to have some coffee and organize the work area.

Works for me. I'll be extending my warmup time from 5 to 15 minutes.

[Bwana Don]

I'm writing a warm-up program today.

[carbidecraters]

We have not warmed up our Fadals in 15 years and havent ever had any spindle issues. Granted we baby our machines a little.

[Neal]

Geof--
I recommend to warm up ANY machine regradless of RPM capacity whether it is a lathe, VMC, Jig Bore, etc. IT does make a difference in protecting the components from thermal shock. Also distributing the oil help to ensure that the machine doe not run with out proper lube.

Neal

[SBC Cycle]

I look at it very simply. I'm not going to start my motorcycle and run it at 5000 RPM cold (yeah, a lot heavier moving parts but you get my drift). Why would I bang my spindle up to 6-7000 RPM when it's cold?

Especially in the winter. It's 57F - 60F in the shop when it's "warm" LOL

[Geof]

Originally Posted by Neal Geof-- I recommend to warm up ANY machine regradless of RPM capacity whether it is a lathe, VMC, Jig Bore, etc......Neal

I agree with you but if you look at the post immediately preceding yours not everyone thinks warm up is needed. I have learnt to waffle in my posts having had people jump on me for making dogmatic suggestions.

What I want though is a system where I can have a robot running around turning on the compressors and starting all the warm up cycles a half hour before my guys get in; we lose 15 to 20 minutes every morning on the warm up cycle.

[Bwana Don]

Tool in the spindle during warm-up or not?