How to Replace the Coil Spring on a Jet Drill Press

The coil spring draws the drill press quill back up after you drill a hole. The coil spring assembly consists of the coil spring, a metal housing, and a backing plate. The spring comes pre-installed in the housing. After years of use, the coil spring might fatigue or break.

Let's get started.

REMOVING THE COIL SPRING   1. Disengage the scale seat.

a. Remove the two screws securing the seat to the body of the drill press.

b. Pivot the seat away from the coil spring assembly.

  2. Remove the coil spring assembly.

a. Remove the outer nut securing the coil spring assembly.

b. Press and hold the coil spring assembly against the body of the drill press.

c. Loosen (but do not remove) the inner nut securing the coil spring (approximately 3/8" from the spring plate).

d. Use a large screwdriver to pry the coil spring assembly away from the body of the drill press. Caution: The spring will uncoil rapidly, so be sure to keep your fingers away from the assembly during this step.

e. Once the spring tension has been released, remove the inner nut from the shaft.

f. Remove the coil spring assembly from the shaft.

INSTALLING THE NEW COIL SPRING

  3. Install the coil spring.

a. Install the new coil spring assembly onto the exposed portion of the feed shaft, aligning the center (straight) leg of the spring with the slot on the shaft.

b. Install and tighten the inner nut until there is approximately 3/8" between the nut and the spring plate.

  4. Tension the coil spring.

a. Protective gloves are recommended for this step.

b. Grasp and rotate the coil spring assembly counter clockwise to add tension to the coil spring.

c. To reposition your hands, press the coil spring assembly against the body of the drill until the inner spring engages the indexing notch on the housing.

d. Continue tensioning the coil spring until the quill assembly retracts into the drill housing.

e. To test the tension of the spring: tighten the inner nut; extend the quill (using the handle bars); then release the handle bars. The quill should retract (spring) firmly and consistently back into the upper housing. If not; loosen the inner nut and increase tension on the coil spring. Repeat this step until the coil spring is ideally tensioned for your specific application.

f. Once the coil spring is ideally tensioned, tighten the inner nut and re-test the quill. The goal here is to tighten the inner nut sufficiently to prevent the coil spring from pulling away from the housing (and uncoiling); but loose enough to allow the quill assembly to glide (extend and retract) freely. Repeat this step until the inner nut is ideally tensioned for your specific application.

g. Use adjustable pliers to hold the inner nut (to prevent it from rotating further).

h. Install and tighten the outer nut to secure the coil spring.

REASSEMBLING THE UNIT

  5. Engage the scale seat.

a. Pivot the scale seat back into position against the body of the drill press and align the mounting holes.

b. Secure the scale seat with the screws.