I salvage from peoples waste bins; this is how I get many of my power tools for free, and one of the most common power tools I get are drills. Many of the power drills I get are good but for needing a minor repair, and one of the repairs needed is a damaged or jammed chuck, like the two drills I am about to repair.
This is a little different from other drill chuck Instructables.
Weather it is for upgrading or repairing; replacing a drill chuck is one of the easiest repairs you can make on a drill when you know how. Many hardware stores have replacement chucks in stock. However there are a couple tricks of the trade to remember when replacing a drill chuck, and this Instructable is on these tricks of the trade.
Step 1: Why Replace the Chuck
Why is replacing a drill chuck necessary; most of the time the reason is neglect or abuse, but sometimes you may want to upgrade a drill. Some drill chucks just won’t grip drill bits as small as 1/16 or 1/32 of an inch, because the flats on the jaws of the chuck make too large of a gap when the jaws are closed. Or you just want to switch to a keyless chuck. Here are some rules to keep your chuck in good shape and the damages breaking these rules can cause.
OK rule number one; ”DO NOT USE TOOLS ON A KEYLESS CHUCK”, the plastic breaks on the plastic keyless chucks and the metal scars on the metal keyless chucks.
Do not tighten or close the jaws of a keyless chuck with a monkey wrench, water pump pliers, or channel lock pliers, these tools will break or damage the chuck. Just use your hand to tighten or close the jaws of a keyless chuck, the chuck is made for that. If you must have the tool in the chuck so tight that you need to use a tool on a keyless chuck, swap out the keyless chuck for a keyed chuck, it is easy enough.
Don’t over tighten keyed chucks; the teeth on the ring gear can break or you can strip the threads on the ring nut or the jaws.
Oil and clean the chuck once in a while, they will seize up if you don’t.
Step 2: Tools and Parts
There are amazingly few tools and parts needed to upgrade or replace most drill chucks.
A screwdriver to remove the setscrew or retaining screw; most of the time a standard, however some have Phillips setscrews, and some newer drills have a Torx screw for the setscrew.
A hammer; for pushing the jaws into the chuck if the chuck is seized.
A pin punch; to help push the chuck jaws in if you need to get at the setscrew and the chuck’s jaws are seized.
A large Allen key or Hex key that will fit in the chuck you are removing.
A replacement chuck and key if not a keyless chuck.
If you work on as many power drills as I do you will find yourself faced with a number of different drill chucks. The most common chucks take four different chuck keys. Three chuck sizes ½ ⅜ ¼, two spindles male and female, two spindle sizes ½ and ⅜, and two torque nonreversible and reversible.
However I will only be replacing two chucks:
⅜ inch reversible Multi Craft chuck
⅜ inch reversible keyless chuck
Step 3: Removing a Working Chuck
I have an old broken drill with a good chuck I can use to make this repair; all I need to do is remove the chuck from the drill.
Removing the chuck can be a bit of a challenge; while the drill is running the chuck and setscrew are made to tighten onto the spindle, this makes them very tight to the spindle. Many nonreversible drills and chucks don’t have a setscrew. Open the chuck jaws until they are fully retracted so you can remove the setscrew. The setscrew is inside the mouth of the chuck. With the drill pointing at you turn the setscrew clockwise to screw the setscrew out of the spindle.
Turn the chuck counterclockwise to screw the chuck off the spindle. Quite often the chuck is so tight to the spindle you will not be able to unscrew the chuck by hand; put a large Allen key or Hex key in the chuck and tighten the jaws on the Allen key.
Tap the Allen key with your hand so it spins the chuck counterclockwise, if using your hand won’t break the chucks lock on the spindle, hit the Allen key with a hammer. You may need to brace the drill on your workbench or vice if you need to hit the Allen key hard.
When the chuck is loose the chuck unscrews off the spindle easily.
Step 4: Opening and Removing a Seized Chuck
If the chuck is seized; place the key in the chuck, and turn the key counterclockwise as you tap on the ends of the jaws with a hammer. Do this until the jaws are fully retracted into the chuck body or flush with the face of the chuck.
Since the chuck jaws need to be fully retracted into the chuck body to remove the setscrew, take a pin punch and tap on the ends of the jaws as you turn the chuck key until the jaws are fully retracted. You may have to tap on the jaws then turn the key, then tap on the jaws then turn the key, until the jaws are fully retracted.
Remove the set screw turning it clockwise
If you cannot close the jaws onto an Allen key; put the chuck key in the chuck making sure the key is not pressing on the ring gear. Tap the key with a hammer so it spins the chuck counterclockwise. If the chuck key is pressing on the ring gear when you hit the key with a hammer it can damage the ring gear or the chuck key. You may need to brace the chuck on your work bench or a vice if you need to hit the key hard.
Step 5: Replacing the Chuck
The new chuck should go on the spindle easily turning it clockwise and the setscrew goes in easily screwing it counterclockwise. And you are done a drill with an upgraded or a repaired chuck.
Step 6: Keyless Chucks
Removing a keyless chuck is the same as removing a keyed chuck. Open the jaws fully, with the drill pointed at you, unscrew the setscrew out clockwise, and unscrew the chuck off the spindle counterclockwise.
If you cannot get the chuck off the spindle with your hands; and you are able to close the jaws of the chuck, put a large Allen key or Hex key in the chuck and tighten the jaws on the Allen key. Tap the Allen key with your hand so it spins the chuck counterclockwise.
If you cannot close the jaws on a Allen key, use a monkey wrench to grip the damaged keyless chuck. If you want to rebuild the old keyless chuck, pad the teeth of the monkey wrench with leather pads.
Screw the new chuck on the spindle clockwise and screw the setscrew into the spindle counterclockwise, and there you have a new chuck on your drill.
Step 7: Free Cordless Drill
I got this $120 cordless drill for no more cost than my time, and parts I salvaged from other drills in the waste bin, not bad if you ask me.