Thinking Cap





Introduction: Thinking Cap

I was struggling with ideas for my next project, then it dawned on me.  I needed a Thinking Hat!

Looking around in my shop, I found I already had all the necessary materials to construct such a time-honored headpiece.  The materials used were:

- an old hard hat
- an old power tube from a previous project (
- a toggle switch
- an "AAA" battery holder (and batteries)
- a "mystery" red LED (I call it a "mystery," because it came unmarked in a box of junk parts I bought once upon a time)
- wire
- an empty wire spool
- an old coiled cord
- a little round "thingy" from an lamp
- a couple of feet or so of brass rod
- solder
- heat shrink tubing
- and my old glue

The tools used were pretty simple: a drill, drill bits, and soldering gun

Step 1: Preparing the Hard Hat

The hard hat stood before me like a pure white canvas (photo 1), ready to be magically transformed into a Hat Of Deep Thinking.

My plan was to mount a huge old vacuum tube on the top (sort of like an "idea" light bulb), stuff a red LED up through the base so it would shine through the glass, and wire it all together with batteries and a switch.

Looking around, I realized that the pins of the tube would fit nicely inside of an old plastic wire spool, so I bolted the wire spool to the top of the hat (photo 2).

Step 2: Preparing the Vacuum Tube

The vacuum tube I used was from the power supply of an ancient television (photo 1).  I began by soldering wires to the leads of the LED, then carefully drilling a hole through the bakelite base and stuffing the red LED all the way up to the base of the glass part of the tube (photo 2).  I had marked the wire for the positive side of the LED before stuffing it inside the tube's base so I wouldn't have to experiment when it came time to wire up the circuit.

Since this was a "mystery" LED, I had no idea what it was rated for, so I began testing by applying 3 volts, and then testing a variety of resistors in the circuit.  I wound up staying with 3 volts and using no resistor.  I suspect this is probably a 5v LED, but 3 volts with no resistor seemed to work fine.

Step 3: Installing the Vacuum Tube

I hot glued the vacuum tube to the empty wire spool I had previously bolted to the hard hat, then made a couple of wire bales that attach to the top of the tube (using some unknown lamp part from my junk drawer), and attaching to the hard hat through holes I drilled.  I reinforced all these attachments with hot glue.

I then attached a coiled cord on the left and right sides (through holes I drilled), and hot glued the center to the unknown lamp part I had placed on the top of the tube.

Step 4: The Electrical Stuff....

The electrical stuff was very simple.  I bolted an "AAA" battery holder inside the hard hat, drilled a hole in the front for a small toggle switch, then hooked it up to the LED wires coming from the vacuum tube.

Step 5: The End Result

I have been noticing that simply wearing the Thinking Hat can make a big difference, but when I want to do some really deep thinking, all I have to do is flip the little toggle switch on the front of the helmet and, WHAM, the thinking really gets DEEP quickly!

If you've ever thought, "Gee, I wish I had a Thinking Hat," I hope this little Instructable will inspire you to make one.  Have fun!



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You should try the pro version 20.00006 it has a multitude of vacuum tubes and empty spools of plumbers tape.

or empty solder spools

Cool, and Is the book your reading upside down?

Yes, it is indeed upside down. It's because of the Thinking Cap, you know.....

Yeah, I figured that out.

I really like the hat, but I REALLY like the photo.

You could adapt a TDCS kit to overclock your brain and make it a real thinking hat! ;)

This made me lol and kinda reminded me of portal for some reason. Now you're thinking with hardhats.

The unknown lamp part is called a harp.

Here is a Demotivation from me to you :)

I love this instructable, by the way.