A Tapping Block
by Richard Cadway
Years ago, I was a journeyman tool and die maker – high-speed progressive dies, fixtures, etc. Now I’m a real estate broker, but I still get in some machining on my own projects.
I have used the process described in the January email tip many times. On the lathe, I often put the tap in the tailstock chuck and push it into the hole while rotating the part by hand.
These methods work great, but it is very easy to break 8-32 or smaller taps. By using a tapping block held against the workpiece and a T-handle tap wrench, I’ve found that I can better feel the cut and am less likely to break the small taps. As long as you have a flat surface square to the hole, this is the fastest and easiest way to start a threaded hole.
The photo shows a tapping block I made back in 1967. It is made of tool steel, hardened and ground. Just make sure to drill the holes a few thousandths over the tap diameter. Small diameter taps will need a counterbored hole due to their shorter length.
As much as I would like to take credit for this block, it wasn’t my idea. I copied it when I was an apprentice. I have probably tapped thousands of holes using this simple tool.
Thanks Richard! Your subscription has been extended by an issue!
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