Frequently Asked Questions About Motor Spindles

A motor spindle is the heart of a milling machine or a CNC-controlled system that drives the tool directly. It combines the motor, bearings and tool holder in a compact housing, enabling high speeds and precise machining. Motor spindles are also referred to as milling spindles, machining spindles or high-frequency spindles (HF spindles).

SPINOGY motor spindles offer numerous advantages:

• Freely configurable: individually adapted to your technical requirements
• High power density: compact design with very low weight
• Upgrade & conversion: existing spindles can be converted or options retrofitted
• Short delivery times: standard < 2 weeks, optionally shortened via express
• Personal contact: direct support from the SPINOGY team
• Professional technical support for installation, maintenance and process consulting
• 3-year warranty on all spindles

We distinguish between the two series X22 and X30, which differ in their size. Within the series, various versions are possible, so that each spindle can be individually adapted to the respective application and freely configured.

Our X22 and X30 spindle series are available with the following tool change types:

• MTC (manual): the tool is changed by hand
• QTC (semi-automatic): the tool holder is changed by hand; tool holders can be pre-measured for fast and precise repeatability
• ATC (automatic): fully automatic tool change for series processes
• DTC (direct tool change): fully automatic tool change without a separate tool holder

Thanks to their configurability, SPINOGY motor spindles are versatile and suitable for numerous industrial applications, including:

• CNC gantry milling machines
• Robotic systems
• Special-purpose machines
• Test benches for rotating applications

Thanks to their compact design and high power density, our milling spindles are particularly suitable for automated and space-critical applications. Private users can also use SPINOGY HF spindles, e.g. for hobby or DIY CNC machines.

Yes – our motor spindles are freely configurable, which is unique on the market. They allow individual adaptation of the cooling type, motor, speed, spindle bearings, sensors and many other options. This means every SPINOGY spindle can be tailored precisely to the requirements of the machine or project.

Important factors when selecting a CNC spindle are:

• Power requirement / torque
• Speed range matching the material and machining
• Cooling (air or liquid)
• Type of tool change and tool interface
• Type and diameter of the tools used

As there are further factors to consider, we offer the opportunity to discuss your application in detail in a personal consultation. Book an appointment now.

With our milling spindles, almost any material can be machined. From wood and aluminium to steel and composite materials – SPINOGY spindles deliver in every application.

With proper use and regular maintenance, SPINOGY motor spindles achieve a service life of several thousand operating hours.

All spindles are manufactured in Germany at our Weiterstadt site – from design to final assembly.

Prices depend on the respective spindle series and configuration. In our online shop, every spindle can be individually configured. Alternatively, we can prepare a quotation. Feel free to book a consultation appointment for this.

The X22 motor spindle is offered in the following basic configuration:

• Power: 2.2 kW (S1)
• Voltage: 230 V
• Number of poles: 2-pole
• Rated speed: 24,000 rpm
• Speed: 30,000 rpm
• Spindle bearings: steel bearings
• Sensors: temperature monitoring at the motor, clamping-position monitoring (ATC), piston monitoring (ATC, DTC), speed sensor (ATC, DTC)

The X22 motor spindle is available with the following power ratings:

• 1.5 kW
• 2.2 kW (basic configuration)
• 3.0 kW
• 4.0 kW

Every X22 HF spindle can be configured as a 2-pole or 4-pole variant.

The X22 motor spindle is available with the following tool interfaces:

• Manual tool change (MTC): ER20, ER25
• Semi-automatic tool change (QTC): HSK-C25, HSK-C32
• Automatic tool change (ATC): SK20, HSK-E25, HSK-E32
• Direct tool change (DTC): 3 mm, 1/8", 4 mm, 5 mm, 6 mm, 8 mm, 10 mm

The X22 motor spindle can be configured with a maximum speed of up to 65,000 rpm, making it ideal as a milling spindle for precise, high-speed machining processes.

The following speed levels are available:

• 25,000 rpm
• 30,000 rpm (basic configuration)
• 35,000 rpm
• 40,000 rpm
• 45,000 rpm
• 50,000 rpm
• 55,000 rpm
• 60,000 rpm
• 65,000 rpm

The X22 motor spindle is a versatile milling spindle and is ideal for machining:

• Wood
• Aluminium
• Plastic
• Composite materials

Other metallic materials such as copper, brass or steel can also be machined well with this HF spindle. For more demanding machining of these materials, we recommend using the X30 motor spindle.

Yes – all speed options up to 65,000 rpm are also available with the air-cooled X22 HF motor spindle. This makes the X22 one of the highest-speed air-cooled high-frequency spindles on the market.

The combination of high speed, compact design and air-cooled technology makes the X22 ideal for demanding applications in CNC milling machines and robotic systems.

Depending on the version, the X22 HF motor spindle has a maximum weight of up to 6.3 kg, making it one of the particularly lightweight high-frequency spindles in its class.

• MTC version: maximum 4.9 kg
• QTC version: maximum 4.9 kg
• ATC version: maximum 6.3 kg
• DTC version: maximum 6.3 kg

Thanks to its low weight, the X22 is ideal for use in robotic systems and dynamic CNC applications.

The exact weights can be found in the respective technical data sheets.

Depending on the cooling variant, the X22 motor spindle is available with different IP protection ratings, so it can be optimally adapted to the respective operating environment.

X22 spindle, air-cooled

• IP20 (basic configuration)
• IP50 optional (with filter mat)

X22 spindle, liquid-cooled

• IP54 (basic configuration)
• IP65 optional

This makes the X22 milling spindle suitable both for clean production environments and for more demanding applications with increased protection requirements, for example in the presence of dust or splash water.

The SPINOGY X22 motor spindle is equipped with two precise GMN spindle bearings:

• 1 bearing at the shaft nose
• 1 bearing at the shaft end

Advantages of the 2-bearing design

• High rigidity combined with a short shaft end
• Less heat generation compared with systems with multiple bearings
• Lower maintenance costs compared with systems with multiple bearings

Bearing options:

• Steel bearings (basic configuration)
• Hybrid bearings / ceramic bearings (optional and depending on the speed option)

This makes the X22 milling spindle optimally suited to different applications and requirements.

Yes – the SPINOGY X22 motor spindle is specifically designed for continuous industrial operation. It runs extremely reliably in 24/7 operation at several customers, including at Geberit on the production line for cisterns.

Yes – the compact design of the SPINOGY X22 spindle makes it particularly suitable for use on robots. Since robots often have only limited payloads, they benefit from our compact and powerful milling spindles. For example, the X22 with HSK-E25 is used by our customer AV&R for polishing turbine blades.

Yes – the SPINOGY X22 high-frequency spindle can be used universally and can be operated on almost any CNC machine. It offers the flexibility to be used in both existing machines and customer-specific systems.

The X30 motor spindle is offered in the following basic configuration:

• Power: 4.0 kW (S1)
• Voltage: 400 V
• Number of poles: 2-pole
• Rated speed: 24,000 rpm
• Speed: 25,000 rpm
• Spindle bearings: steel bearings
• Sensors: temperature monitoring at the motor, clamping-position monitoring (ATC), piston monitoring (ATC, DTC), speed sensor (ATC, DTC)

The X30 motor spindle is available with the following power ratings:

• 3.0 kW
• 4.0 kW (basic configuration)
• 5.0 kW
• 6.0 kW

Every X30 HF spindle can be configured as a 2-pole or 4-pole variant.

The X30 motor spindle is available with the following tool interfaces:

• Manual tool change (MTC): ER25
• Semi-automatic tool change (QTC): HSK-C32, HSK-C40
• Automatic tool change (ATC): SK30, HSK-E32, HSK-E40

The X30 motor spindle can be configured with a maximum speed of up to 45,000 rpm, making it ideal as a milling spindle for precise, high-speed machining processes.

The following speed levels are available:

• 20,000 rpm
• 25,000 rpm (basic configuration)
• 30,000 rpm
• 35,000 rpm
• 40,000 rpm
• 45,000 rpm

Yes – all speed options up to 45,000 rpm are also available with the air-cooled X30 HF motor spindle. This makes the X30 one of the highest-speed air-cooled high-frequency spindles on the market.

The combination of high speed, compact design and air-cooled technology makes the X30 ideal for demanding applications in CNC milling machines and robotic systems.

The SPINOGY X30 motor spindle is ideal for the heavy-duty machining of steel. At the same time, it can also be used excellently for aluminium, wood, plastic and composite materials, making it very flexible for a wide range of machining tasks.

Depending on the version, the X30 HF motor spindle has a maximum weight of up to 12.9 kg, making it one of the milling spindles with a particularly high power density.

• MTC version: maximum 9.7 kg
• QTC version: maximum 9.8 kg
• ATC version: maximum 12.9 kg

Thanks to its high power density, even smaller CNC milling machines or robots with lower payloads can be equipped with significantly more power

The exact weights can be found in the respective technical data sheets.

Depending on the cooling variant, the X30 motor spindle is available with different IP protection ratings, so it can be optimally adapted to the respective operating environment.

X30 spindle, air-cooled

• IP20 (basic configuration)
• IP50 optional (with filter mat)

X30 spindle, liquid-cooled

• IP54 (basic configuration)
• IP65 optional

This makes the X30 milling spindle suitable both for clean production environments and for more demanding applications with increased protection requirements, for example in the presence of dust or splash water.

The SPINOGY X30 motor spindle is equipped with two precise GMN spindle bearings:

• 1 bearing at the shaft nose
• 1 bearing at the shaft end

Advantages of the 2-bearing design

• High rigidity combined with a short shaft end
• Less heat generation compared with systems with multiple bearings
• Lower maintenance costs compared with systems with multiple bearings

Bearing options:

• Steel bearings (basic configuration)
• Hybrid bearings / ceramic bearings (optional and depending on the speed option)

This makes the X30 milling spindle optimally suited to different applications and requirements.

Yes – the SPINOGY X30 motor spindle is specifically designed for continuous industrial operation and is suitable for multi-shift operation, so it works reliably even under continuous load.

Yes – the high power density of the SPINOGY X30 spindle makes it particularly suitable for use on robots. Since robots often have only limited payloads, they benefit from our compact and powerful milling spindles. In this video you can see the SPINOGY X30 in action on a Kuka robot.

Yes – the SPINOGY X30 high-frequency spindle can be used universally and can be integrated into almost any CNC machine. It offers the flexibility to be operated reliably in both existing machines and customer-specific systems.

SPINOGY motor spindles offer a wide range of individual configuration options to adapt them optimally to the respective application:

• Cooling type: air or liquid cooling
• Tool interface: MTC, QTC, ATC, DTC
• Motor: power, voltage and number of poles
• Maximum speed
• Spindle bearings: steel or hybrid bearings
• Temperature sensors: e.g. at the motor winding head as well as at the bearings (front and rear)
• Speed sensors: inductive sensor or encoder
• IP protection rating
• Connections: straight or angled
• Personalisation / branding: e.g. with your own logo
• Warranty extension

This allows the motor spindles to be tailored precisely to different applications and requirements – from standard solutions to customer-specific special versions.

Depending on the selected power rating, SPINOGY HF spindles use either asynchronous motors or synchronous motors.

SPINOGY X22:

• 1.5 kW – 3.0 kW: asynchronous motor
• 4.0 kW: synchronous motor

SPINOGY X30:

• 3.0 kW – 5.0 kW: asynchronous motor
• 6.0 kW: synchronous motor

The choice of motor type depends on the desired power and torque characteristics of the motor spindle.

Depending on the power rating, SPINOGY high-frequency spindles are available with 230 V or 400 V.

• 1.5 kW to 3.0 kW: 230 V & 400 V
• 4.0 kW to 6.0 kW: 400 V

This allows the spindles to be flexibly integrated into different machine and system concepts.

With the motor options for SPINOGY spindles, you can choose between a 2-pole and a 4-pole motor in every power class.

The key difference lies in the rated speed:
at the same frequency, a 2-pole motor reaches roughly twice the speed of a 4-pole motor.

This also shifts the power range:

• 2-pole motors are optimised for high speeds
• 4-pole motors deliver their torque and rated power in a lower speed range, but reach the same speeds as the 2-pole motor

4-pole motors are therefore particularly suitable for applications with higher torque requirements at low speeds, such as drilling and thread machining or when using larger tools. In other words, wherever torque is more important than speed.

Potting the stator has the following advantages:

• Improved heat conduction: heat is dissipated more efficiently, enabling higher continuous power and a reduced thermal load
• Increased mechanical stability: protection against mechanical loads
• Longer service life: improved cooling significantly reduces ageing of the insulation
• Noise reduction: the potting reduces vibration of the windings and thus the noise generated by the spindle.

The difference between steel and hybrid bearings lies in the material of the rolling elements:

With steel bearings, both the bearing rings and the balls are made of steel.

With hybrid bearings, the bearing rings are made of steel, while the balls are made of ceramic (e.g. silicon nitride).

Advantages of hybrid bearings:

• Higher speeds due to lower centrifugal forces
• Lower friction and thus reduced heat generation
• Improved running smoothness and higher rigidity
• Electrical insulation within the bearing

Steel bearings are a robust and cost-effective solution for applications with moderate speeds and are therefore used in the basic configuration of all our milling spindles.

Both air and liquid cooling can be used without issue in 24/7 continuous operation. The choice of the right cooling method depends rather on the requirements of the respective application.

Air cooling:

• Quick and easy commissioning (no cooling unit or hoses required)
• More cost-effective, as no additional peripheral devices are needed
• Lower space requirement, as no external cooling unit needs to be installed

Liquid cooling

• Very efficient cooling (coolant absorbs more heat than air)
• More constant temperature → higher precision, less thermal expansion
• Very quiet operation
• Suitable for high ambient temperatures
• Enclosed housing (IP54 or IP65) → ideal when using cutting fluid
• Longer maintenance intervals thanks to the enclosed housing, as neither the filter mat nor the cooling channels need to be cleaned
• Temperature control of the spindle possible

Yes – air-cooled SPINOGY motor spindles can optionally be equipped with a filter. Retrofitting is also easily possible on existing spindles.

The use of a filter is recommended in particular for applications in which fine particles or dust are generated that could be drawn into the spindle by the fan.

Alternatively, a liquid-cooled SPINOGY milling spindle can be used for complete encapsulation of the spindle.

In SPINOGY ATC spindles, tool clamping is monitored via integrated sensors:

Sensors (standard):

• 2 sensors for monitoring the clamping position (tool clamped / released)
• 1 sensor for monitoring the piston position

How it works:

• Use of inductive sensors
• Output as a digital signal:
  • 24 V (High) = signal active
  • 0 V (Low) = signal inactive

This ensures reliable detection of the clamping status as well as high process reliability during automatic tool change.

Speed control means that the full torque is available from 0 rpm. Without control, the maximum torque is only available from approximately 5,000 rpm.

Practical advantages:

• Full torque even at low speeds
• Ideal for drilling and thread machining
• Ideal for heavy-duty machining
• Particularly powerful in the lower speed range in combination with 4-pole motors

SPINOGY motor spindles offer various options for temperature monitoring:

PTC at the motor winding head (standard configuration):

• Temperature sensor integrated as standard
• Switching threshold for overtemperature monitoring
• Connection to the drive → automatic shutdown when exceeded

Additional PTCs (optional):

• Integration at the front and/or rear bearing possible
• With multiple sensors: cascade connection
• Triggering of one sensor leads to shutdown of the spindle

PT100 (optional temperature measurement):

• Can be used at the motor winding head as well as at the front and/or rear bearing
• Continuous recording of the actual temperature values
• Ideal for monitoring and predictive maintenance

SPINOGY motor spindles can be equipped with various speed sensors.

• Inductive speed sensor (basic configuration for ATC and DTC)
• Encoder, analogue 1 Vpp (sin/cos)
• Encoder, digital TTL

Application:

• Speed monitoring
• Speed control
• Absolute positioning of the spindle shaft (only possible with an encoder)

Yes, thread cutting or rigid tapping is possible with SPINOGY milling spindles.

Requirements:

• Encoder option for precise position monitoring of the spindle shaft
• 4-pole motor option recommended for optimal torque in the low speed range

Yes – SPINOGY motor spindles can also be used for drilling. The 4-pole motor option is recommended for this.

Sealing air is an air flow used in many motor spindles to protect the bearings from dust, chips or liquids.

Disadvantages of conventional sealing-air systems:

• Permanent compressed-air supply required
• High energy costs, especially in continuous operation

SPINOGY solution:

• No sealing air → no additional energy costs
• Protection of the bearings by an innovative 5-stage labyrinth seal
• Effective protection against foreign particles without compressed air

Every SPINOGY spindle can be individually personalised from a quantity of 1. There are two options:

• Personalisation: your own logo on the right or left side of the spindle
• Branding: we omit our logo on the front of the spindle and laser your logo on instead

All SPINOGY spindles are delivered with the corresponding set of screws for mounting the spindle. In addition, depending on the spindle, you receive the following additional items:

• MTC: mini clamping nut, spindle clamping wrench, shaft clamping wrench
• QTC: anti-seize metal paste for the clamping set
• ATC: anti-seize metal paste for the clamping set

Yes – we are a system supplier. Any accessory for operating our motor spindles is available from us. This includes:

• Electrical and pneumatic control
• Cooling system and accessories
• Clamping tools

Visit our online shop to find the right accessories for your spindle

A frequency inverter is required to control a SPINOGY high-frequency spindle.

Options:

• Directly with the appropriate accessories: mains filter, braking resistor, connecting cable
• Plug & play solution: ready-to-use Xcontrol-E motor spindle control, including all components required for safe operation.

Yes – the frequency inverters are supplied parameterised to match the respective spindle configuration.

No – one advantage of SPINOGY motor spindles is that the spindle holder is already integrated into the spindle, unlike conventional round spindles.

In addition, our intelligent mounting system allows the spindle to be bolted either from the front or the rear.

The Xcool is a cooling unit developed and manufactured in-house by us and tailored precisely to our motor spindles.

Advantages:

• Waste heat from the spindle is dissipated optimally
• The spindle always operates within its optimal operating temperature range
• Maximum performance and service life of the spindle

The Xcontrol-E (electrical control) and Xcontrol-P (pneumatic control for ATC and DTC) controls offer the following advantages:

• All components are already mounted and wired, integrated into a control cabinet
• Plug and play: quick commissioning – ready to use straight away

Yes – after a prior check by our service technicians, we ensure that the external accessories are compatible with the SPINOGY spindles.

SPINOGY can be reached by phone and email Monday to Friday between 08:00 and 17:00.
Alternative options:
o Book a consultation appointment
o WhatsApp support: +49 6150 970 96 80 – available at any time

Yes – SPINOGY offers application and process consulting. In a consultation, we review your application together and give tips for optimal milling results.

Book process consulting now

Yes – we provide all the necessary CAD files in advance so that you can check your design with our spindle.

Alternatively: the CAD models of every spindle can also be downloaded directly as a STEP file in the online shop.

• You receive a standard 3-year warranty on all SPINOGY motor spindles
• The warranty can optionally be extended to up to 6 years
• We grant a 2-year warranty on all other products

For more information, please see our service and warranty terms. (Available on request)

SPINOGY delivers motor spindles and all accessories worldwide.

• Basic configurations: usually available from stock, shipped within 2–3 working days
• Individual spindle configurations: delivery time approx. 2 weeks
• Express option (surcharge): prioritised processing within 1 week or 3 days

• Within Germany: free shipping from an order value of €150
• International: shipping costs depending on the number and weight of the packages

Yes – we provide the complete documentation for the spindles and accessories digitally.

Yes – we provide support with commissioning by email, phone or online meeting. Thanks to experience with a wide range of common CNC controls, we support the integration of our components and ensure fast commissioning.

• Book a commissioning appointment

For long and reliable operation, the spindle should be serviced regularly.

The maintenance intervals depend on the intended use and the duration of use.

Typical maintenance work by the user:

• Cleaning the spindle and accessories
• Cleaning or replacing filters (if present)
• Retightening the fastening screws
• Checking connecting cables and hoses for a secure fit
• Re-greasing the clamping system
• Function test of all sensors
• Annual coolant change

Specific maintenance intervals are defined in the operating manuals.

In addition, maintenance by SPINOGY is possible at any time. This also allows potential problems to be detected and remedied early.

Yes – the experienced assembly team at SPINOGY has extensive experience in repairing motor spindles from a wide variety of manufacturers.

• Standard: approx. 2 weeks for maintenance or repair
• Express option (surcharge): prioritised processing within 1 week or 3 days

Yes – if a loan spindle is available, it can be rented for 30% of the net new price for the duration of the repair. Alternatively, we offer an express repair.
We also recommend having a second spindle available on site as a replacement spindle to avoid system downtime through a quick exchange.

The cost of replacing the bearings of a SPINOGY motor spindle depends on the respective spindle type and the bearings installed. After receiving and inspecting the spindle, we prepare a transparent cost estimate with all the necessary work and spare parts.

The calculation is made up of various flat rates:

• Maintenance flat rate
• Balancing flat rate
• Flat rate for the front bearing replacement
• Flat rate for the rear bearing replacement

During a bearing replacement, the spindle is not only fitted with new bearings but also fully serviced, inspected and rebalanced. This ensures that it is subsequently in a technically flawless condition again.

Yes – options can be retrofitted or an existing spindle can be converted.

Yes – we also offer B-stock or refurbished spindles. These are technically flawless, have new wear parts and merely cosmetic defects. You can find all available B-stock and refurbished spindles in the online shop: Discover now