Introduction: Collets and Chucks

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COLLETS ARE THE BEST OPTION FOR HOLDING SMALL DIAMETER PARTS.

A collet is an easy method for holding small diameter parts. Each collet is sized to fit a specific diameter, and
must fit snugly. The collet is threaded into the end of the spindle, after the chuck is removed and the collet clamps down on the workpiece.

  1. Press the E-stop.
  2. Select a collet that is the correct size for the workpiece.
  3. Ensure that the outside of the collet and the inside of the spindle are clean.
    • Wipe with a clean shop towel.
  4. Engage the spindle lock.
  5. Slide the collet into the spindle.
  6. Slide the material into the collet.
    • Never close an empty collet.
  7. Push the collet closer handle towards the tailstock (to the right).

  8. Rotate the collet closer ring to pull the collet deeper into the spindle.
    • Stop when you feel a bit of resistance.
  9. Flip the tab on the collet closer ring to keep the ring from rotating.
  10. Release the spindle lock.
  11. Move the collet closer lever to the left to secure the material.
    • When closing, you should feel a "click" as the mechanism engages.
    • If you don't feel the click, tighten the ring and try again.
    • If the mechanism is too tight, loosen the ring and try again.
  12. Rotate the workpiece by hand to ensure the spindle is unlocked.

Step 1: Chucks

CHUCKS ARE USED FOR HOLDING LARGE WORKPIECES.

There are several common ways to hold materials on the lathe. Usually, the 3 jaw chuck is installed on the
lathe. It is a self centering chuck, meaning that all the jaws move together, and keep the workpiece centered. The 3 jaw chuck only works on round material, or materials with a number of sides divisible by 3.

  • A 6 jaw chuck works the same way, with the same rules.

For holding square, rectangular or odd shapes, a 4 jaw chuck can sometimes be used.

  • See Shop Staff for 4 jaw chuck use.

Using the 3 or 6 jaw chuck

  1. Press the E-stop to ensure safety.
  2. Use the chuck key to open the jaws.

  3. Place your part in the jaws.
    • The workpiece must be inserted into the jaws deep enough for a secure grip.
  4. If more than 3x the workpiece diameter is sticking out of the chuck, you must use a center to hold the end. For example, if the material is 1" in diameter, and 4" is sticking out of the chuck, use a center.
    • To help center the workpiece in the chuck, wiggle it when tightening the jaws.
    • Ensure that there is enough material sticking out of the chuck to keep the tool from hitting the chuck.
  5. Tighten the jaws with the key.
    • Remove the key.
  6. Rotate the chuck by hand to ensure that the material is centered and that there is no interference between the chuck and any other part of the lathe.

USING A LIVE CENTER

  1. Insert a drill chuck and center drill in the tailstock.
  2. Slide the tailstock 1" from the workpiece and lock it.
  3. Turn on the lathe.
  4. Set the correct RPM.
  5. Extend the quill until you drill into the workpiece about 1/4".
  6. Turn off the lathe and replace the drill chuck with a live center.
  7. Move the tailstock close to the workpiece and lock it.
  8. Extend the quill until the center is snug in the workpiece.
  9. Lock the quill.