Dremel manufactures a line of rotary tools for drilling, grinding and woodworking. The company's power tools use a patented collet-and-chuck locking system to hold bits for different applications and to allow a quick change-out of bits. For safety's sake, it is important to understand how to remove and securely install Dremel bits.
Press and hold the silver-coloured Shaft Lock Button near the front edge of the tool.
Unscrew the metal collet nut on the end of the shaft by turning counterclockwise.
Unscrew the plastic housing cap front at the end of the tool by turning counterclockwise.
Remove the collet from the motor shaft. The collet is a small, metal, silver-coloured tube wider in the front than the back, which inserts into the motor shaft.
Place the collet inside the metal collet nut.
Insert a Dremel bit through the collet nut and firmly into the collet. The Dremel tool comes with four collet sizes, so use a larger collet to accommodate the shank of larger Dremel bits. The bit should fit snugly inside the collet, with no wiggle or play back and forth.
Thread the plastic housing cap back on the tool but do not tighten.
Insert the collet into the drive shaft with the Dremel bit inside the collet and the collet nut over the assembly.
Tighten the collet nut by hand and press the locking button when the nut is seated to secure the collet and Dremel bit. You will hear a click indicating the drill bit is locked.
Hand tighten the housing nut and pull on the drill bit to ensure it is secure. Your Dremel tool is now ready to use.
The Dremel tool is designed to not operate if any of the collet parts are installed incorrectly. Even so, as a safety precaution, unplug the tool while changing the bits.
Wear safety goggles when using power tools.