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Silver aluminium flexible shaft coupler 5mm to 8mm

Unique-Bargains

Unique-Bargains CNC Motor Shaft Coupler 5mm to 8mm

SKU CH-V6AC-2PKJ4

Connects a 5 mm motor shaft to an 8 mm shaft with an aluminium flexible coupling that uses grub screws for a secure, non-marring grip

  • Product typeMotor Shaft Coupler
  • Connects 5 mm and 8 mm shafts for flexible motion transfer
  • Aluminium construction reduces rotational inertia for responsive performance
  • CNC machining delivers precise fit without damaging shaft surfaces
  • Grub screws secure shafts with flats for reliable torque transmission
  • Compact 20 x 25 mm size fits tight engine compartments

CNC Motor Shaft Coupler 5mm to 8mm

This aluminium coupler connects a 5 mm shaft to an 8 mm shaft in drone and RC engine builds. It is supplied new and weighs 18 g. The CNC finish provides an extremely tight grip without marring the shaft surfaces. Grub screws are included to secure the connection on shaft flats.

Capacity and headroom

The 20 mm diameter by 25 mm length body fits standard motor mounts while the aluminium construction keeps rotating inertia low. It handles the torque demands of typical hobby drivetrains but is not rated for high-power industrial loads. Builders needing larger bore combinations or higher torque capacity will need a different coupler.

Build integration

The silver tone coupler slides into place and locks with the provided grub screws, requiring only a hex key for installation. Its compact 20 x 25 mm footprint leaves clearance for adjacent components in tight airframes. The lightweight design helps maintain the mass balance of small electric power systems.

How it compares

Measured against everything we stock in Boat Engine Components & Locks, at today’s prices. Recalculated every night.

Price $6.99
Typical for this category: the median of 21 items is $6.99.

Specifications

Product
Product typeMotor Shaft Coupler

Questions about this item

Will the 5 mm bore fit the motor shaft I already use on my RC plane?

The coupler has a 5 mm inner diameter on one side, so it matches a 5 mm motor shaft directly.

How can I confirm the grub screws are holding the shafts securely after installation?

Tighten the grub screws against the shaft flats, then rotate the assembly by hand — no slippage means the grip is solid.

Does the package include anything besides the single aluminium coupler?

The box contains only the 20 mm by 25 mm coupler; no extra screws, tools or adapters are supplied.

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