[QuinnSjoblom]

I have a 2.2kw water cooled spindle. havent ordered a water pump yet and after some research i read that many guys dont even bother cooling the spindle if they arent pushing it, so i went ahead and ran a few cuts. Longest one about 10 minutes long. Afterwards i put my hand on the side of the spindle and it was barely above ambient temp. With the type of cutting im doing, im probably only using a few percent of the spindles capability. I just went with the 2.2kw for the er20 and the ability for plenty of power if i need it. As long as the spindle isnt heating up, am i ok to skip the cooling until i start pushing it harder? Obviously ill cap the cooling fittings to keep shavings out.

[ger21]

Yes, you should. I only know of one person running a water cooled spindle with no water, and he has it in the airstream of his dust collector.
If you don't want to buy another, you should connect the water cooling system.

[QuinnSjoblom]

ok, ill add the pump. honestly im a bit paranoid after hearing reports of these chinese spindles leaking internally and destroying it. If the spindle is only 100f or so on the outside, could it really be overheating on the inside? Ive read reports from a few guys that ran for years with no water and no issues because they were barely loading the spindle like myself, but if you think its needed even though the outside isnt warming up at all, ill trust your judgement.

[ianagos]

I think you’d be fine running without it for maybe 10 to 15 minute runs but that’s like saying I’m fine to run my car with low coolant for a few minutes because the block is still cold. Maybe you could get away without it? But do you want to take the risk? I just don’t think the risk is worth not setting up the pump. Remember that’s how it was designed to work. Now as far as the leaking well that’s just low quality chinesium manufacturing.

[ChuckC]

Pressure test your setup. Hook up an air gauge and hook in line a tire valve type fitting. everything available from hardware store. Pressure up low-at up to twice hydraulic pressure, maybe-though that should still be quite low. I'd guess less than 15 to 20 psi. See how long it holds. Look for leaks-if sealed properly it should hold for a while, I'd think.

[jfong]

When I first recieved my 2.2kw spindle, I did a quick power on test without water. I set the parameters on the VFD, and ramped up the RPM to 24krpm. After about 5 minutes the spindle got pretty warm and I shut down. Internally it probably got much hotter. It’s been several years now and the VFD/spindle has been working great but I will never run without water cooling again.

[QuinnSjoblom]

Ok, I'll do a leak down test. If I can trust it won't leak, I have nothing against running water. I already have the plumbing ran through my chain. I probably won't put 15 or 20 pounds on it though. If the seals aren't great I'm sure some pressure will blow them. Running water through is basically no pressure. I'll try 5 pounds or so and see if it holds. Actually I guess I could probably just put 2 short sections of tube on, fill with water till it rises an inch or so up the tubes, then plug one tube and suck on the other tube. Should see bubbles rising if there's a leak.

[ianagos]

Ok, I'll do a leak down test. If I can trust it won't leak, I have nothing against running water. I already have the plumbing ran through my chain. I probably won't put 15 or 20 pounds on it though. If the seals aren't great I'm sure some pressure will blow them. Running water through is basically no pressure. I'll try 5 pounds or so and see if it holds. Actually I guess I could probably just put 2 short sections of tube on, fill with water till it rises an inch or so up the tubes, then plug one tube and suck on the other tube. Should see bubbles rising if there's a leak.

That’s a good method you can use a hand vacuum pump or something similar too if you wanted.
I also agree with you that 20psi would blow it.

[ChuckC]

You might not want to use vacuum, especially if Festo (push-to-lock) fittings are used as they work great under pressure, but leak under vacuum. I'd concede on pressure values, I'm just using typical hydrostatic test rules (1.5 to double working pressure to proof).

Still, if you can find a way to pressurize it and let it sit, that's the way to ensure tight fittings...

Good luck and let us know how it works...

[ianagos]

You might not want to use vacuum, especially if Festo (push-to-lock) fittings are used as they work great under pressure, but leak under vacuum. I'd concede on pressure values, I'm just using typical hydrostatic test rules (1.5 to double working pressure to proof).

Still, if you can find a way to pressurize it and let it sit, that's the way to ensure tight fittings...

Good luck and let us know how it works...

This guy sounds like he knows what he’s talking about. Forget what I said.

[QuinnSjoblom]

ok, ill go with gentle pressure.

[coherent]

I personally went with a air cooled spindle simply because I didn't want the hassle of dealing with the water, pump and reservoir. I read somewhere where someone added their own fan cooling setup to a water cooled spindle, but I have my doubts as to how well it worked and for how long. I think if folks don't want to mess with the water cooling setup... just get an air cooled spindle to start with. The prices are fairly comparable and I haven't read any reports of huge longevity differences. Especially for hobby users or if daily production use and extended/all day run times is not likely.

[ChuckC]

coherent, -

What about noise levels of air versus water cooled? I like the idea of simplicity and will be upgrading my Kress spindle, which is crazy loud for my tastes... I don't have an issue with wiring up plumbing around electronics; been there, done that - just it's a bunch more to fiddle with.

Still, If it cuts the noise down to less than, say 85dBA running free then that's enough for me. It's not that the spindle gets a work-out, it's annoying working around such high noise levels (even though I'd wear ear muffs with either, I guess).

Please share your results -

Chuck

[A_Camera]

coherent, -

What about noise levels of air versus water cooled? I like the idea of simplicity and will be upgrading my Kress spindle, which is crazy loud for my tastes... I don't have an issue with wiring up plumbing around electronics; been there, done that - just it's a bunch more to fiddle with.

Still, If it cuts the noise down to less than, say 85dBA running free then that's enough for me. It's not that the spindle gets a work-out, it's annoying working around such high noise levels (even though I'd wear ear muffs with either, I guess).

Please share your results -

Chuck

In my opinion the noise issue is just unreal.

https://youtu.be/gjjpohihwU0

OK, my measurements may not be scientifically 100% accurate but I think it is good enough. I measured 1 meter from the spindle (which is the norm for noise measurement) using an app in my phone. Anyway, in my experience the cutting noise is widely higher than the spinning noise, so unless you intend to cut air only, I would not worry about the noise. It is definitely far below any other air cooled motors I have in my home, like angle grinders, circular saws, table saw, drill machines, Dremel tool and so on, especially compared with the same rpm.

[A_Camera]

...am i ok to skip the cooling until i start pushing it harder?

I would not run a water cooled spindle without cooling. Even if it may survive some use, it can't be good for it because it is designed for having liquid cooling. If you have second thoughts about water cooling systems (which I had when I was about to decide for a spindle) then you should bite the bullet and buy an air cooled spindle, but I don't think it is a good idea to run a water cooled motor without cooling, not even if you only use it lightly.

[ger21]

What about noise levels of air versus water cooled?

Air cooled noise levels can vary greatly from spindle to spindle, as the noise is created by the cooling fan.

The round spindles I have are very quiet, but don't move much air through them.
I've heard square ones that were quite loud, as they moved a lot of air, and most likely ran much cooler.

I'f noise is that big of a concern, you probably shouldn't be using a CNC machine.

[coherent]

I have used both air and water cooled spindles. Both types I've seen are fairly comparable and much much quieter than something like a PC 690 router when not cutting. Once the bit hits the wood, the cutter noise level exceeds either one anyway. Mine is the round type. It barely gets warm and I can easily hold a conversation with the air cooled spindle running if not cutting. In fact the dual APC fans/blowers in my control box are louder than just the spindle. Granted, I haven't cut anything that takes 20-30 hrs to cut but no issues after 3-4 hours straight of continuous use, or 8-10 hrs of use throughout a day.

[QuinnSjoblom]

Just wanted to give an update. Tested my spindle for leaks, it's fine. Hooked up the pump. Water goes in cold and comes out just as cold so I really think it probably would have been fine without it with the type of cutting I'm doing but at least now I know for sure.

[ChuckC]

The phone apps that are used for doing sound level measurements are actually quite accurate; I'm an Industrial Hygienist (so that's my gig) and we tested them against some of our lab instrumentation. It was amazing how close the phone apps were compared to our $10,000 spectrum analyzer...

Thanks for the Vid! Awesome demonstration as you just can't get an appreciation until you experience it. I'm surprised that the air cooled ones are nearly as quiet. I'm still going to go to the trouble of liquid cooled, however.

Chuck