We here at Gimson Robotics are one of the most popular suppliers of linear actuators, DC electric motors and control accessories in the UK, with full product support and user advice available.
Unlike some cheaper re-sellers all of our items are thoroughly tested and covered by a 1-year limited warranty. We are highly knowledgeable in our field, insured, and VAT-registered.
Take a look at our other eBay listings for related products (and sometimes B-grade items available at a discount).
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Please contact us if you are ordering from a VAT-registered business in an EU country (excluding the UK) or from a country outside of the EU.



The GR-WM1 gearmotor on this listing is a 12V DC (nominal) motor and gearbox combination featuring a three-stage 98:1 reduction gearbox. The first gearbox stage is a worm and wheel meaning that the transmission cannot be back-driven once in position. All six gears are constructed of metal with the output stage spur gears a relatively large 1.25 MOD size allowing for high torque transmission.

The no-load speed at 12V DC after the gearbox is 62rpm reducing to 52rpm at the maximum efficiency torque output of 25kg-cm (2.45Nm, 347oz-in). Short term torque output may exceed 100kg-cm. The motor may be operated at anywhere between 3-12V, with a maximum continuous output of 24W at 12V. 



This gearmotor provides an ideal solution for applications requiring a high output torque from a compact device which doesn't demand high levels of current. The right-angle output shaft can also enable the motor to fit in positions that planetary and conventional spur gear motors wouldn't be able to.

Special effects, DIY, robotics and automation projects could all benefit from the steady output speed and the resistance to being rotated, provided by the worm and wheel stage once the motor is in a position. 

As with any brushed DC motor it is possible to vary the output speed by regulating the supplied current with a PWM speed controller, and to change the direction of rotation by swapping the polarity of the supplied current. We also stock power supplies, rocker switches, remote switches and speed controllers that are ideal for controlling these motors, please contact us or search 'Gimson Robotics' for more information.

The motor is a '595' type, with a 36mm can diameter. It features a cooling fan towards the rear of its body to enable high duty cycle operation (high duty cycles are possible when the motor is operating in one direction only, not if it has to regularly change direction). For continuous usage (100% duty cycle) please don't exceed 25kg-cm of torque at 12V, and ensure that the rear of the motor is well ventilated. 

By default the motor comes without an input cable and you would need to solder or crimp wires onto the two copper tabs to operate it, we do however offer the option to add either a 2.1x5.5mm male DC connector lead (approx 280mm long) or a 500mm long length of red and black silicone insulated leads, to make connecting the motor to power and control hardware much easier - please contact us if you would like a lead adding.

If you require a motor with greater torque output and a sturdier (12mm) output shaft then please search for our 24V 'GR-WM2' model (eBay does not let us use direct links). 




Gearbox Build Detail:
Size:The gearbox body is 58 x 58 x 37mm overall (excluding output shaft)
The motor itself is a maximum of 38mm diameter by 71mm long
The overall motor and gearbox size is 130 x 60 x 55mm including output shaft
Mounting:Three M4 (6mm deep) threaded holes on the front face of the gearbox (the same side that the output shaft extends from)
Body material:Steel and aluminium
Gearbox type:97.5:1 ratio, three-stage (worm and wheel first stage then two spur gear stages), all metal construction
Shaft type:10mm diameter by 17mm long with a 16mm long 'D' flat
Shaft support:Dual ball-bearings, both 12mm bore
Weight:680g (including lead and connector)

Operating Characteristics:

at 6V DC:
at 12V DC:
No-load motor speed:3050rpm6100rpm
No-load speed after gearbox:31rpm62rpm
No-load current:0.2A0.35A
Maximum efficiency torque:12.5kg-cm25kg-cm
Maximum efficiency speed after gearbox:
26rpm52rpm
Maximum efficiency current:1.3A
2.6A
Stall torque:75kg-cm150kg-cm
Stall current:
6A12A

Some of the above figures are theoretical and may vary between motors and gearboxes. Please allow for +/-5% on most values. 

So as not to damage the gearbox ensure that it is not allowed to reach stall conditions, either mechanically or by limiting the current available to the motor (the simplest way of doing this is adding a fuse in series with the input).



If you have any questions about this item please contact us via eBay messaging or by using the contact page of our website.