AndyMark EVO Shifter Short Hex Shaft, StageA 3 Stage - 25.90:1 Ratio 1.14:1, StageB 3 Stage - 05.45:1 Ratio 1.14:1
Offers shift-on-the-fly with two-speed gearbox
Features improved 4-tooth dog shifting method
Optimizes performance with pneumatic shift method
Includes multiple encoder options for precision
Supports aggressive weight reduction design
The AndyMark EVO Shifter Short Hex Shaft, StageA 3 Stage - 25.90:1 Ratio 1.14:1, StageB 3 Stage - 05.45:1 Ratio 1.14:1 represents a significant advancement in shifting transmission gearboxes. This two-speed, shift-on-the-fly gearbox is designed with an improved 4-tooth dog shifting method, allowing for smooth and efficient transitions between gears. It is compatible with two CIM or NEO motors and can be configured with either two or three interior stages, offering flexibility in performance. The gearbox is shipped assembled, though motors are not installed, even if included in the order.
The EVO Shifter incorporates several enhancements over previous models, including a robust 1/8" diameter shoulder screw and a dog gear made from AMPCO® 18 Bronze, which provides added lubricity for smoother shifting. The gearbox features a high 85:15 first stage reduction, and users can independently select their high and low ratios, allowing for customizable performance. The gearbox also includes a super-strong shift block assembly with a larger bearing and threaded steel housing.
The pneumatic shift method utilizes a spring-extend pneumatic cylinder, enabling shifts while a robot is accelerating, pushing, or decelerating. This design ensures that the robot can continue to operate using Ratio A if air pressure is lost. The gearbox is designed for aggressive weight reduction, with machined gears and plates, and can be mounted to an AM14U family chassis or a 2"x1" box tube frame.
The EVO Shifter offers more encoder options, including the US Digital E4T and the CTRE SRX mag encoder. The gearbox requires grease for optimal operation, with a recommended break-in period before applying grease to ensure smooth performance. The encoder ratio for the two-stage version is 3:1, providing precise control and feedback.
Note: Proper installation of the pinion gear requires specific procedures, including the use of a 3-ton arbor press for NEO motors and the application of red Loctite 271 for CIM motors to ensure secure attachment.
1x AndyMark EVO Shifter Short Hex Shaft, StageA 3 Stage - 25.90:1 Ratio 1.14:1, StageB 3 Stage - 05.45:1 Ratio 1.14:1
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This return policy also applies, as a minimum standard, to products sold and fulfilled by third-party vendors through the Marketplace.
United Kingdom consumers exercising their statutory Right of Cancellation are subject to different conditions. See the Statutory Right of Cancellation.
Returns under this policy concern non-defective products. In the case of a confirmed manufacturing defect, remedies are handled under the Warranty terms, at the Vendor's discretion. See the Warranty section.
Return Conditions
To qualify for a refund under the 30-day return policy, all of the following conditions must be met:
A valid Return Authorisation (RA) number must be obtained prior to returning the product. Returns without an RA number will be refused.
The RA number is valid for 30 days. The returned item must be received within that period.
The RA number must be included with the return.
Products must be returned in unused, unmodified condition (e.g., no scratches, alterations, missing parts, or signs of installation/use) and in their original packaging, suitable for resale.
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Refunds are processed within 7 days after receipt and inspection of the returned item.
A £100 cleaning fee may apply to domestic robots returned in used or unclean condition.
A 20% restocking fee may apply to large-quantity returns of items ordered specifically for the customer from the manufacturer or not part of RobotShop's standard inventory.
Return Exceptions
The following products are not eligible for return or refund under this policy:
Used, damaged, or modified products — Items that show signs of use, wear, or alteration, making them unsuitable for resale.
Consumables * — Use and wear-and-tear components, altered or depleted through use (e.g., batteries, belts, brushes, gears, filament, tyres, disposable bags, lubricants, greases, waxes, etc.). Not eligible for return once opened or used.
Perishables — Goods liable to deteriorate or expire rapidly. Not eligible for return.
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Digital Goods, Software, and Apps * — Final sale only, due to licensing restrictions.
Clearance Items * — Products identified as clearance or final sale, including end-of-life or discontinued items.
Custom-made, personalized, or special-order items — Products manufactured, configured, adapted, or built to the customer's own specifications and requirements.
On-Demand Items * — Standard catalogue products not stocked by RobotShop and ordered specifically to fulfil a customer request.
* United-Kingdom consumers retain their statutory Right of Cancellation on these items. Its exercise is subject to the conditions and exclusions set out in the Statutory Right of Cancellation, and any reimbursement may be reduced to reflect a loss in value resulting from handling beyond inspection.
How to Request a Return Authorisation (RA)
While the same return policy applies, these orders require a separate contact process for returns.
RobotShop Fulfilled Orders → submit a support ticket from your account under My Support Tickets.
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Note: Marketplace vendor products are normally labelled with SKUs starting with RM, and identified on the product page with the mention "Sold and fulfilled by [Vendor Name]".
