Blade Clamp
Affiliate link — we may earn a commissionA blade clamp is the mechanism that holds and releases the blade in a reciprocating saw or jigsaw. Modern recip saws use a tool-free blade clamp: you twist a lever or push a button, insert the blade tang, and release. The spring-loaded mechanism locks the blade in place. Older saws required an Allen wrench to change blades. Jigsaws use T-shank or U-shank blade clamps. T-shank is the modern standard, with the blade clicking into place. U-shank is the older style that requires a setscrew. If you're buying a jigsaw, get one with a T-shank clamp. U-shank blades are increasingly hard to find.
Why It Matters
On a demolition job, you might change recip saw blades 10 to 20 times in a day. A tool-free clamp saves real time. More importantly, a worn or damaged clamp lets the blade wobble or eject during cutting. If the blade feels loose, replace the clamp mechanism before the blade comes out at speed.