FAQ Spindles

You can find answers about the most frequently-asked questions about spindle service below.

Should you have questions which were not answered here, please come to us with your questions.


Questions related spindle service

Where should defective machine spindles be sent?

Please send defective machine spindles to:

GMN Paul Müller Industrie GmbH & Co. KG
Äußere Bayreuther Str. 230
90411 Nuremberg, Germany

However, if it is a “protected” model, the repair must be handled by the machine manufacturer.

What is included in the spindle repair process?

After a machine spindle is received, it is given a visual inspection, and on occasion, an incoming test run. As a rule, the machine spindle must be disassembled to provide a complete analysis of the damage and/or wear. Then GMN creates a cost proposal related to the extent of damage, the possible cause of the failure, repair costs and the time needed for repair. The repair is started only after the cost proposal is approved.

How often can a machine spindle be repaired?

A machine spindle can theoretically be repaired as often as needed. Of course, GMN will advise you if a repair no longer makes economic sense; for instance if the repair costs are not reasonable as compared to the price of a new item.

How is a repaired machine spindle different from a new spindle?

The test criteria tolerances are the same for a repaired spindle as for a new spindle. Also the scope and process of the final inspection of repaired and new spindles are absolutely identical. This means that one can expect the same running characteristics as a new spindle when a repaired spindle is returned.

Does one receive an inspection protocol for repaired spindles as well?

Of course. Since repaired spindles undergo the same inspection procedures as new spindles, an inspection protocol will naturally be created, just as with new spindles. The acceptance criteria are the same here as with a new spindle.

Are GMN machine spindle repairs only carried out in Nuremberg?

No, they are not. GMN has developed a global network of authorized repair partners; repairs can be performed near the user. You can find the  list of our branch sites and partners here.


However, if it is a “protected” model, the repair must be handled by the machine manufacturer.

Can I receive assistance in commissioning my machine spindle?

Our service technicians are available to support you with the commissioning of a GMN machine spindle.

The machine spindle must be mounted in accordance with the installation instructions. All required supply systems must be correctly installed and connected to the machine controls and the machine spindle. The supply systems (coolant chillers and oil air lubricators) must be filled with the recommended products. All required media (air, power, etc.) must be available in sufficient volumes and of the correct quality. Staff who are sufficiently trained to operate the machine must be available.

Can one also order accessories and supply systems directly from GMN?

GMN offers tool holders (such as grinding mandrels and abrasive mandrel banks, disc flanges) as well as supply systems (such as lubrication devices, cooling systems) which are configured specifically for GMN machine spindles. Please send us a request, or contact your local representative.

Can I also order spare parts for my machine spindle if I would like to repair it myself?

As long as it isn’t a “protected/proprietary” model, you can order most parts and components from GMN to repair your GMN machine spindles.

Whom can I contact if I have further questions?

The contact data for responsible partners at our factory can be found here. You can also call us directly at our hotline at +49 (0)911 5691 600.