Star Trek Geological Tricorder Build

In my opinion, this “glob” on the backside of the Tricorder upper door is not what we have thought that it was….


For years, the theory was that this was a glob of epoxy used to keep the door shut. Actually, this glob is too low on the door to make contact with the upper aluminum cross bar of the Tricorder frame.

So what is it??

It appears that when they replaced the original Season 1 door pulls with the later version, the new door pulls ended up being too proud on the backside of the door(essentially sticking out of the backside of the door). Remember, the Desilu prop shop ripped out the middle compartment when they disassembled and duplicated the heroes for the fiberglass midgrades and never put the middle compartment guts back into the heroes. So, it didn’t matter that the new door pulls were too proud on the back of the door, in order to close it.

Here is the proof from the surviving hero in the Jein collection:

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Continuing this line of thinking…

It looks like they tilted the top cross bar downward to try to use a friction fit to keep the upper door shut and not falling open….


They may also have installed small black grub screws to keep the door from falling inward into the Tricorder body…

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Test fitting and shaping up the overall body and shells, today….I have a lot of work to do with the side panels…


The side panels on the original Geo Tric appear to be sanded to a pretty thin profile, as does the surviving Jein Hero. I think that we tend to leave these with a pretty thick profile on our builds.


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Quick update…

I completed the blinking “destress beacon light” today…

I used several “warm LEDs” to simulate 1960’s lighting instead of a vintage incandescent (I was worried about the heat buildup that would be a certainty).



I adapted a simple circuit board that I picked up on eBay and adjusted the blinking speed to match with timing of the screen used Tricorder. The build does not make any sound.

To get an even diffusion of the LED lights in the brass light box, I mounted the LEDs in the bottom compartment of the Tricorder, so that they shine upwards into the light box. I also lined the light box with highly reflective silver mylar and mounted 2 layers of vellum paper behind the milky acrylic piece.

Now it’s on to the final fit and finish of the Kydex shells, mounting the leather strap, etc….
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I forgot to update this thread, but I wrapped up this build about a week ago.






I did add two small screws (to serve as doorstops) to prevent the middle door from being pushed into the “distress signal” light box. These screws seem to be present on the Jein original as well, possibly installed after the middle compartment guts were removed (which would be prior to the third season)

My build:


The Jein original:


This was a really fun build to knock out.
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