Shaft Coupler - 1/4" to 6mm

These stainless steel shaft couplers allow you to couple two size shafts together. They can be used for connecting motor shafts to drive shafts, or two different-sized shafts. These shaft couplers have a length of 0.75”, a outer diameter of 0.42”, and couple 1/4” to 6mm shafts.

Actobotics is a robotics building system based around extruded aluminum channels, gears, precision shafts, and ball bearings. Thanks to the two standardized hole patterns, nearly all Actobotics components can be intuitively connected together. The wide range of components makes building complex electromechanical prototypes or finished projects a reality.

  • Length - 0.75”
  • Diameter - 0.42”
  • Bore A ID - 1/4”
  • Bore B ID - 6mm

Shaft Coupler - 1/4" to 6mm Product Help and Resources

Core Skill: Robotics

This skill concerns mechanical and robotics knowledge. You may need to know how mechanical parts interact, how motors work, or how to use motor drivers and controllers.

1 Robotics

Skill Level: Noob - You will be required to put together a robotics kit. Necessary parts are included and steps will be easy to follow. You also might encounter basic robotics components like bearings, mounts, or other hardware and need a general idea of how it goes together.
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Core Skill: DIY

Whether it's for assembling a kit, hacking an enclosure, or creating your own parts; the DIY skill is all about knowing how to use tools and the techniques associated with them.


Skill Level: Noob - Basic assembly is required. You may need to provide your own basic tools like a screwdriver, hammer or scissors. Power tools or custom parts are not required. Instructions will be included and easy to follow. Sewing may be required, but only with included patterns.
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Looking for answers to technical questions?

We welcome your comments and suggestions below. However, if you are looking for solutions to technical questions please see our Technical Assistance page.

  • Member #475848 / about 9 years ago / 1

    Does this come with the set screws? w1bwx's comment suggests that it doesn't, but was that just an error? If not, has it changed since 10 months ago?

  • Member #459200 / about 10 years ago / 1

    So what did you do? I planned to order the coupler but without set screws its worthless.

  • w1bwx / about 10 years ago / 1

    No set screws included! Arrrrgghh!

Customer Reviews

4 out of 5

Based on 2 ratings:

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just what i ordered

everything fit just as advertised could not be happier

Well designed and constructed.

This coupler is the perfect accessory for connecting a 6mm shaft to a 1/4" shaft. Made from stainless steel is a bonus for anti-corrosion. It fits both shafts well and is easy to tighten and secure. Definitely recommended.