Shaft Coupler - 1/4" to 1/4"

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 1/4” 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 - 1/4”

Shaft Coupler - 1/4" to 1/4" 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 #1063463 / about 6 years ago / 1

    Tolerances on the coupler seem good enough. However, on the set screws, a 3/32 hex key is too big and a 5/64 is too small....anyone else have a similar experience?

  • Member #626788 / about 6 years ago / 1

    Prepare to lose these set-screws. I was setting something up on an optical table (a large metal table with regularly spaced screw holes that allow you to bolt things to the table), and one of these set screws fell down a hole, never to be seen again. It would be nice if Sparkfun provided the size of the screws so that you could go order more, or better yet, they could provide a spare screw with the shaft coupler.

  • These require a 3/32" hex key.

Customer Reviews

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shaft couple

good finish, smooth bore, finished edges. High priced!