Everyone knows calipers have jaws for outside and inside measurements. Most people know the little bar at the bottom is a depth gauge.
But a lot of people don’t know there’s a fourth way to measure with calipers — and it’s the best way to set up your marking gauge or square.
Say you’re cutting a half lap and need to mark exactly halfway through the thickness of a board.
First, use the calipers to measure the thickness of the board. Make sure to measure where the half lap will actually be.
Divide that measurement by half and set the calipers to that number. Lock it down tight.
Ken Roth
February 22, 2023
I’ve been using calipers for years and never knew about the (secret) 4th use of calipers—it really took me by surprise! Thank you Jonathan!