How to Change the Speed of a Drill Press

Changing the spindle speed for a manual drill press requires physically adjusting belts between pulleys.  In this example, we have three pulley sets two belts on a JET drill press.  The original speed is 540 and we will be changing it to 1840.

I made this at TechShop Detroit (www.techshop.ws).

This critical first step is to unplug the drill press.  This is to ensure that while your hands are in the dangerous area of spinning pulleys, an accidental machine start does not harm you.

The top of the drill press holds a panel that can be flipped open to show the three pulley sets.

There are two locking screws on either side of the drill press.  Loosen both screws to allow for the motor to be moved.  The screws are located beneath the panel on either side.

Pulling the motor lever brings the motor closer to the pulleys and the pulleys closer to each other.  Note the difference when the belts are not pulled taut.

To change the speed to 1840 from 540 both belt positions must be changed.  The "left" belt will change to a position second from the bottom.  The "right" belt will changed to the bottom position.

The first belt to be removed is the belt on top, which in this case is the "right" belt in the picture.  Lift the belt on the pulley set where the pulleys decrease in size from bottom to top.  Carefully lift the belt while rotating it on the pulley.  Keep your fingers on the outside of the belt to minimize the chance of your fingers getting caught.  Once the belt is loose, move it so that it will not be in the way when you remove the "left" belt.

Repeating the same process, lift the belt on the pulley set where the pulleys decrease in size from bottom to top.  Carefully lift the belt while rotating it on the pulley.  Keep your fingers on the outside of the belt to minimize the chance of your fingers getting caught.  Once the belt is loose, move it so that it will not be in the way

In this case, the "right" belt will now be on the bottom position since we are changing to the speed of 1840.  Put the belt in the correct position on the pulley set where the pulleys increase in size from bottom to top.  Then put the other side of the belt in the correct position on the other pulley set.

The "left" belt will now be on the second from the bottom position since we are changing to the speed of 1840.  Put the belt in the correct position on the pulley set where the pulleys increase in size from bottom to top.  Then put the other side of the belt in the correct position on the other pulley set.  Verify that both belts are in the correct position.

Pull the motor lever back in place.  The belts should now be taut.

Tighten both the locking screws on either side of the drill press to keep the system in place.

Close the belt access panel.

Plug the drill press back in... and you're ready to go!  The speed has been changed from 540 to 1840.