Getting a Craftsman Drill Press 103 Replacement Chuck Right: Fit, Tools, and Final Checks

The 103 prefix on a Craftsman press points to a specific era and builder, and it tells you something useful about the chuck: these are older machines, so the chuck may be worn, the taper may be an older size, and a retaining screw is a real possibility. A Craftsman drill press 103 replacement chuck is a rewarding repair that brings an old machine back to accuracy, and the fit and final checks are what keep you from ordering the wrong taper for a press this age.

Replacing the chuck means separating the old chuck from the spindle and seating a new one. On a 103 series Craftsman the chuck sits on a Jacobs taper arbor, and that arbor seats in the spindle on a Morse taper. Chucks of this age often add an internal retaining screw.

The direct answer: unplug the press, check for and remove any internal retaining screw, drive the old chuck off with wedges, then seat a new chuck on clean, dry tapers matched to your measured taper. Measure rather than assume, since a 103 series press may use an older or smaller taper than modern presses.

Confirm before you buy

With the press unplugged:

• Open the jaws fully and look down the bore for a retaining set screw, often reverse threaded. Remove it first.
• Measure the arbor’s Jacobs taper. JT33 is common, but an older 103 press may differ, so measure.
• Measure the spindle’s Morse taper, confirmed by the arbor that fits.
• Decide chuck only or chuck and arbor. A worn or scored arbor means replacing both.

Removing the old chuck

1. Open the jaws fully.
2. Slide drill chuck removal wedges between the chuck and the arbor collar, one each side.
3. Tap evenly, alternating sides, until the chuck releases square. Support it.
4. To drop the arbor, feed the quill down and drive a taper drift through the slot with a soft dead blow mallet.

Fitting the new chuck

1. Wipe both tapers bone dry. No oil on a friction fit.
2. Seat the arbor into the spindle with one firm push.
3. Seat the new chuck onto the arbor with a straight axial push against a wood block.
4. A matched replacement drill chuck with JT33 arbor sized to your measured taper takes out the guesswork.
5. Chuck a straight pin and indicate the runout with a dial indicator.

Where people go wrong

The first mistake is assuming a 103 series press uses a modern taper and ordering the wrong chuck. The second is missing the retaining screw common on chucks this age and hammering one still bolted on. The third is oiling the taper, which lets the chuck creep off under load.

The verdict

A replacement chuck restores the accuracy an old Craftsman 103 was built with. Unplug it, remove any retaining screw, and measure the Jacobs and Morse taper rather than assuming a modern size. Pull the old chuck with wedges, seat the new one on clean, dry tapers with one square push, and indicate the result. Measure for the era and the press grips and drills true again, without a mismatched part or a built in wobble.

Three takeaways:

1. Measure the taper; a 103 era press may differ from modern.
2. Remove any retaining screw before driving the chuck.
3. Seat the new chuck dry and square, then indicate the runout.

FAQ

How do I replace the chuck on a Craftsman 103 drill press? Unplug it, remove any internal retaining screw, drive the old chuck off with wedges, then seat a new chuck on clean, dry tapers matched to your measured Jacobs and Morse taper.

What does the 103 prefix mean? It identifies the builder and era of the press. It tells you the machine is older, so measure the taper and expect a possible retaining screw rather than assuming modern specifications.

What taper does a 103 series press use? Often a JT33 Jacobs taper at the chuck and a Morse taper at the spindle, but an older press may differ. Measure yours before ordering.

Does it have a retaining screw? Chucks of this age often do. Open the jaws fully and look down the bore. A screw at the bottom is a retaining set screw, often reverse threaded, and must come out first.

Should I replace the arbor too? Only if the arbor taper is worn or scored. A matched chuck and arbor set covers both joints when the arbor is also worn.

Why does my new chuck wobble? Usually the taper did not seat square, often from oil or a sideways tap. Clean it dry and reseat with one straight push, then indicate.

How true should it run? A few thousandths of runout is normal on a home machine. Visible wobble means reseat the taper or the arbor is worn.

References

1. Zoro Resource Hub, Morse vs. Jacobs Tapers. https://www.zoro.com/resourcehub/what-are-the-dimensions-and-angles-of-morse-tapers-and-jacobs-tapers/
2. Occupational Safety and Health Administration, Woodworking eTool: Drill Presses. https://www.osha.gov/etools/woodworking/production/machines-tools/drill-press