Monday, September 6, 2010

A Micrometer Stand

When you acquire a micrometer and begin making use of it, you soon discover that miking tiny parts with it is a very clumsy bit of business. You truly need a third hand, and the stand pictured does the job.

Before I built this, I looked into getting a ready-made one. They can be had, but not nearby or inexpensively. It somewhat surprised me that such a useful accessory for a micrometer would be such an obscure item.

Anyway, since I much prefer working to shopping, I went on a scrounge around my workshop and came up with the makings of a stand in short order.

The base is a steel, 3 1/4" diameter pulley. The pulley is heavy enough that the stand isn't tippy. A 4" spring clamp serves nicely for holding the micrometer. Two 3/4" corner braces and a few fasteners and washers provide the hinged mounting arrangement that permits adjustment of the micrometer's viewing angle.

The screw for the pivot-point is Loctited into a threaded hole in the lower corner brace, so the screw never loosens when the wing nut is loosened for adjustment. I should add a second screw or an interference-fit pin where the clamp is attached to its corner brace, so the clamp can't twist out of position sideways.

I won't hold my breath waiting to win any industrial design awards for it, but for the price it's been serving me well. (By the way, that oversize 1/4"-20 wing nut was once the cover fastener for a Ford Pinto's air cleaner. Think what you will of the Ford Pinto, they were good basic transportation, and they had fine air cleaner cover wing nuts.)

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Thursday, September 9, 2010


I finally got around to doing what I should have done in the first place, I added a roll pin to the clamp/corner-brace attachment point so the clamp can't get torqued out of position.

This is a handy technique for securing interfaces against rotation when you have very little room for an additional threaded fastener. Drill one small hole, install a roll pin, problem solved.

That roll pin is tiny. It's 1/16" diameter x 3/16" long, but it's all that's needed.

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