Thread: The Difference Between Water-cooling Spindle and Air-cooling Spindle Mini CNC Router

Isn't the precision of the spindle related to the precision of the axis stepper motors?

I think he means play and/or end float in the spindle bearings themselves, not in the stepper motor positioning. I read one article on a person's homebrew CNC where he could measure thermal expansion as the rails warmed up during the day!

I have had both water cooled and air cooled Chinese round style spindles (all 80mm dia and 1.5 kw), and I would never buy a water cooled one again.

My experience has been that the air cooled units have never even got warm.

And I don't have to provide all that water cooling paraphernalia.

YMMV.

Originally Posted by Greolt

I have had both water cooled and air cooled Chinese round style spindles (all 80mm dia and 1.5 kw), and I would never buy a water cooled one again.

My experience has been that the air cooled units have never even got warm.

And I don't have to provide all that water cooling paraphernalia.

YMMV.

And they don't die from water leakage through the motor/bearings etc as a few have reported in the forums over time.I did a lot of time driving a commercial unit with a 10KW air cooled spindle, it never gained more than a couple of degrees over ambient temp regardless of how hard it was pushed, or how long it ran (sometimes 90+ hrs per week). It was fairly compact for a motor as well, about the same size as the 2KW single phase motor on my compressor.

Would I be correct to say that water cooled have one slight advantage in that they can be run at less than 100 Hz and therefore have the spindle rotate at less than 6,000 RPM?

Craig

I've read the air cooled ones are much noisier?

Originally Posted by Smirkin

Would I be correct to say that water cooled have one slight advantage in that they can be run at less than 100 Hz and therefore have the spindle rotate at less than 6,000 RPM?

Craig

Nope. Don't know about the hobby-size spindles, but we run our machine at work (9kw air-cooled) at 3k rpm for drilling. AFAIK, as long as your inverter/controller can handle it you can run at whatever speed you like, you just won't have maximum power below ~6-8k rpm (your machine may be higher or lower, but those are common speeds)

Originally Posted by pippin88

I've read the air cooled ones are much noisier?

I've never heard a water cooled spindle, so I can't comment on that, but once you put a bit in and start cutting the spindle noise pretty much irrelevant.

Originally Posted by Smirkin

Would I be correct to say that water cooled have one slight advantage in that they can be run at less than 100 Hz and therefore have the spindle rotate at less than 6,000 RPM?

If we are talking about the round bodied Chinese HF spindles, then there is no difference between water cooled and air cooled models that I have used.
As far as I can tell they have the same armature and specifications. One has a fan and the other a water jacket. The air travels through the same space that is sealed and filled with water on the other

Originally Posted by pippin88

I've read the air cooled ones are much noisier?

Again, if we are talking about the round bodied Chinese HF spindles, then there is no difference that I can tell between the noise of either type. They are very quiet. All the noise comes from the bit in the wood.

Originally Posted by elanjacobs

............ but once you put a bit in and start cutting the spindle noise pretty much irrelevant.

I agree with a proper spindle, however if we were to be talking about a router as spindle (which we are not) then the noise can be significant before cutting anything. And is often far more than the bit cutting.

Originally Posted by Greolt

I agree with a proper spindle, however if we were to be talking about a router as spindle (which we are not) then the noise can be significant before cutting anything. And is often far more than the bit cutting.

Fair point. On that note, why ARE routers so damn loud?

Originally Posted by elanjacobs

Isn't the precision of the spindle related to the precision of the axis stepper motors?

precision based on stepp moters also ,also based on spindle and ball screw

Originally Posted by elanjacobs

Fair point. On that note, why ARE routers so damn loud?

Brushed cheap design maybe, not to sure but I prefer a spindle and would take a Air over water any-day the first spindle I set up was water cooled that's all you could get then and it ended up dying because of it.

I find the more expensive the spindle the less its associated with water, most water cooled spindles appear to be of the very very cheap versions, they do the job.

I have one water cooled spindle and two air cooled spindles at work, the air cooled ones never get hot and they can be running at 24000 rpm for upwards of 12hrs non stop

I believe the poster is simply trying to sell products, hence the link to there website in there speil...

Steve