A bunch of electrometers on the wrong hat.

A hat full of electrometers - Table of Contents

The electrometer hat band is finally finished.

I got my wife to help me make the band itself out of black cloth last weekend. We cut a strip of cloth about 5 centimeters (2 inches) wide, then I marked seven spots front and center on it for the electrometers. My wife made button holes at those seven spots, then we folded it over and sewed it together the long way. We then turned it inside out so that the seam is inside the band.

Hat band and electrometers
Hat band and electrometers

You can’t really see the button holes, but they are there.

Once we got it all sewed together, I took it to to my workbench and installed the electometers.

I soldered the (really limp, silicone insulated) wires to a piece of stiff wire then used it to pull the wiring through the insides of the band.

Wiring the hat band
Wiring the hat band

It took maybe a half an hour to string them all together. Contrary to my wife’s dire predicitions, I did not make a single burn mark on the band. There’s a lot of things I can’t do, but I can solder.

All strung up and working
All strung up and working

I took the band and the electrometers downstairs then, along with a sewing needle and a roll of black thread.

It took a couple of hours to sew the electrometers in place. There was a constant stream of “sigh” (pulled the thread out of the needle eye) and “ouch” (poked myself in the finger) while we were watching TV - I’m not good with a needle.

Once I got it all together, I put it on my hat to try it out:

Finished, but on the wrong hat
Finished, but on the wrong hat
Finished, but on the wrong hat - 2

I didn’t have my daughter’s hat at hand, so I made do with one of mine.

The electrometers do work, but they mostly indicate the charge state of the hat. They do change slowly in response to things around them, they just don’t react as well or as fast as they did alone.

I gave it to my daughter the next day when I visited her to help out with some work in her house, but we didn’t have time to dig out her witch hat and make pictures. If she makes any pictures of it, I’ll post them here.

A hat full of electrometers - Table of Contents