Couplings for Motors and Lead Screws

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Couplings to Connect Motor Shafts to Lead Screws

Couplings are good at making sure your motor shaft fastens to the lead screw. Couplings are simply used to enable a motor to turn a lead screw, or other type of shaft. There are two types of couplings, rigid (one piece), and flexible (an assembly of pieces). Flexible couplings are composed of two hubs and a central spider. One hub is fastened to a motor shaft with a set screw. The other hub is fastened to the lead screw end. The rubber spider enables the two hubs to connect and turn while still allowing for a bit of flexibility in alignment and angle. Below, you will find rigid couplings and coupling sets that include two hubs and one spider for common uses, and you can purchase coupling hubs and spiders separately. Please read the conditions of purchase prior to purchasing any products offered by BuildYourCNC.com.

Rigid Coupling (Steel) - 1/4" to 1/4" (1/4" bores at each end)

Rigid couplings will keep backlash to a minimum, since the coupling is one single piece.

Generally, the motor shaft with a 1/4" diameter will be inserted in one end, and a shaft, or lead screw also measuring 1/4" in diameter will be inserted into the other end. The screws that clamp the shafts will be tightened. These steel clamping coupling are for use with high torque motors and high inertia when the motor is changing directions.

1/4" to 1/4"

Rigid Coupling (Steel) - 1/2" to 1/2" (1/2" bores at each end)

Generally, the motor shaft with a 1/2" diameter will be inserted in one end, and a shaft, or lead screw also measuring 1/2" in diameter will be inserted into the other end. The screws that clamp the shafts will be tightened. These steel clamping coupling are for use with high torque motors and high inertia when the motor is changing directions.

1/2" to 1/2"

Rigid Coupling - 1/4" to 1/4" (1/4" bores at each end)

Rigid couplings will keep backlash to a minimumn, since the coupling is one single piece. Generally, the motor shaft with a 1/4" diameter will be inserted in one end, and a shaft, or lead screw also measuring 1/4" in diameter will be inserted into the other end. The screws that clamp the shafts will be tightened, but not too much. These types of clamping couplings will not damage the shafts.

1/4" to 1/4"

Rigid Coupling - 1/2" to 1/4" (1/4" bores at each end)

With this coupling, the motor shaft with a 1/2" diameter will be inserted in one end, and a shaft, or lead screw also measuring 1/4" in diameter, or vice versa, will be inserted into the other end.

1/2" to 1/4"

Coupling Sets - Connects a single motor to a lead screw end

We have an assortment of bores (shaft diameters) from which to choose. How to choose, the first measurement is one side and the second measurement is the opposite side, pretty simple. Say you have a 1/4" motor shaft, and the lead screw is 5/8", you will need a 1/4" to 5/8" coupling. Each coupling comes in three parts, two hubs and one insert.

1/4" to 1/4"

1/4" to 3/8"

1/4" to 1/2"

1/4" to 5/8"

$11.00 - 5/16" to 1/4"

Note: For the products below, to create a complete coupling set, you will need two hubs (one for the motor shaft and one for the lead screw end) and you will need one spider. These items are only offered to allow for any configurations that is not offered above.