Measuring a Taper
© Frank Ford 2006; Photos by FF

It's a Hawaiian guitar "steel" and I'd like to make some more like it. I'll need to measure its taper to set up my lathe:

This is a quick method I learned while reading one of the home machinist forums.

First, I set the steel upright on a nice flat surface.  My surface plate was, as usual, covered and buried over in the corner, so I chose my mill table.  Laying a 1-2-3 block on its side, I could hold my digital caliper flat on top of the block, squeeze it to contact the steel, and set the readout to zero:


Repeating the same caliper technique using the block with the two inch dimension turned upright, I was certain that my caliper was exactly one inch higher, and by closing the caliper down, I got an immediate readout of the taper per inch:

This is a technique I'll never forget. . .


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