One of the hard decisions is air vs. water cooled. I’ve been reading various forums to learn more about water cooled spindles, and have come to the entirely predictable conclusion that it depends. But here’s what I’ve found so far.
I’m reading about people’s experience with both types, across a wide variety of spindle types, trying to learn more. I feel like a complete tyro since I haven’t even got the current setup finished, so I’m really looking for relevant experience that these quotes make you think about.
The other benefit of liquid cooling is power of the spindle. It’s common that an air cooled spindle will lose more than 40% of the power when it’s in continuous use. A liquid cooled spindle will not see a power loss because the operation temperature is constant.
I haven’t checked the temperature of our 9hp HSD air cooled spindle, but it gets hot.
In my experience, air cooled is the most reliable and the one that requires the least amount of attention. With liquid cooled this one may be the most effective method, but it is also the one that is most overlooked, …
For a 1.5kw or 2.2kw spindle I prefer the water cooled. I have a 1.5kw water cooled UGRACNC spindle on my current Techno Isel 4x4 cnc. I ran a 2.2kw HSD air cooled spindle on my previous PAE 4x4 cnc. Both have been used in my studio for production of HDU molds for concrete artwork.
My primary reason is that the air cooled spindle makes more noise. Even with my ever-present hearing protection, the noise difference is noticable. The closed-loop water pump and cooling system from UGRACNC works perfectly.
You should not need air assist. Instead, I use a “gas spring with ball-joint fittings” form McMaster-Carr on my Z axis to offset the weight of the spindle. The air cooled spindle weighs less than the 3.25 Hp Porter Cable router that it replaced. I chose a gas spring with “available force” similar to the weight of the Z axis and spindle added together, and a stroke a few inches greater than my Z axis movement. Not very expensive. No maintenance required.
Gas spring makes a lot of sense here for a large spindle, regardless of air or water cooling.
On to another site…
I have owned about 10 of the Chinese spindles in the 1-2kw range. Both air and water cooled. Round and square bodies. All air cooled models were shaft driven fans, so they do make more noise than electric fans from the popular Italian spindles. I also have a friend that supplied WC spindles as an option on OEM machines.
It appears that there was far more problems with those early (read as cheap) cooling systems than with the spindles themselves. Manu users were taking cheapo aquarium pumps and placing them in a 5 gallon bucket. Eventually the pump plugged or burned out, which burned down the spindle.
There is no reason that you cannot get long service if you put in a closed cooling system.
So it looks like going with a CW-3000 unit instead of an open bucket or cobbled-together pumps would be a good idea. Not super expensive. In fact, maybe cheaper than cobbled-together based on what I’ve seen.
I know this has been silent for a while, but just as a reference in case somebody is looking. I run water cooled too with a 3x3 1.5kw machine I built.
As a life long (50+ years) whose ears have paid the bill for his hobby, liquid cooled spindles ARE quieter, and that’s a good thing.
I have fairly sensitive hearing (classical music aficionado here) so quieter makes a lot of sense and I’m more likely than most to notice.