First, let’s take a look at Hydrostatic Spindles individually. What are the differences between hydrostatic and more common rolling element spindles?

Hydrostatic spindles combine high vibration resistance, high static stiffness, and high rotational accuracy, which ultimately gives them a longer lifespan. These advantages allow the unit to perform progressive precision grinding processes.

• These spindles typically have Angular Contact or Roller Bearings.  
• Hydrostatic spindles have critical bearing surfaces on the OD of the spindle shaft and the ID of the spindle housings.  These components float on a film of oil that acts as both the lubrication method and the bearing itself.
• The hydrostatic spindle bearings are most commonly found in grinding spindles but are sometimes present in milling and other spindles.  

So what are the advantages of Hydrostatic bearings over Rolling Element Bearings (aka angular contact and roller bearings)?

Hydrostatic Bearings are externally pressurized fluid bearings. They have a very high load carrying capacity, high damping, and high stiffness. This means the CNC machine tools that use hydrostatic spindles can be used for an extremely long time without having to be rebuilt.

So why not use Hydrostatic bearings all the time?

Hydrostatic spindles can have speed limitations. Also, if any type of contamination occurs, they will fail quickly. Contaminates that get inside of the spindle will cause the OD of the shaft to rub on the ID of spindle housing, which will create premature failures.

What should you do if you experience hydrostatic spindle failure?

Few companies have the knowledge, experience, or machine tools to effectively rebuild hydrostatic spindles; however, we do at Motor City Spindle.

Here are a few videos showing one of our technicians, Tom Allman. grinding critical components on our Kellenberger K100 machine. This precision ID / OD Grinding machine can hold extremely tight tolerances that allow us to re-manufacture  spindles to like-new and even better-than-new conditions.

It’s all about the spindle component sizes, fits, clearances, and geometry. These configurations need to be perfect, which is why we love our Kellenberger K100 machine.

Interested in learning more about the K100? 

Interested in getting a FREE QUOTE on a CNC spindle repair? 

Reach out to a Motor City team member today!

Sales@MotorCityRepair.com