wayouteast
Sr Member
I've been working on upgrading some of the details of my Hasbro proton pack, and as part of that process, I wanted to build myself a version of a perhaps somewhat undervalued connected prop - the 'belt gizmo' that the Ghostbusters wear on their utility belts. As far as I'm aware its function is (at least canonically) undetermined, but there is one school of thought that it may act as either a monitor or a controller or a safety device for the proton pack itself. There is a main board in a leather holster connected to a daughterboard clipped to the belt.
In the first film, the main board component of the gizmos was the de-cased guts of a Sanyo ICC-808D calculator, while the daughter boards were each different and cobbled together from random electrical components. The most striking feature of the main boards was the array of 'Nixie tubes' at the top - numeric cathode displays that were the precursors of modern alpha-numeric LED displays (though these are never shown illuminated in the movie - at least not visibly).
In the second film, the gizmos were much cruder - literally painted dummy boards - and the Nixies were replaced with glass tubes containing a short length of rainbow ribbon cable!
I wanted to base my version on the more detailed first film gizmo. Of course, after nearly 40 years the original calculators are rare, and expensive when you find them. You can still get Nixie tubes - mainly from Eastern Europe - but they are usually a different style and, again, quite costly. For my purposes, I was quite content to settle for a final result that emulated the original props in appearance but without necessarily being completely accurate in every detail - especially given the generally ramshackle, hand-built and cobbled-together aspect of much of the Ghostbusters equipment.
In the end, I opted for 3D-printed resin boards and modern 7-segment LED displays inside lengths of clear, acrylic tube to mimic the Nixies. I also wanted to add a bit of animation and light-effects to the gizmo that was a bit more subtle than just flashing coloured LEDs - as if it was actually displaying some sort of data readout from the pack.
I found some quite nice affordable STLs on Cults3D by MrKiou and printed the various parts on my Elegoo Mars printer (I had to use Meshmixer to cut the main board into 3 pieces to fit it on the plate and then reassemble them later). I moulded and cast the 'E' display in red-tinted clear resin, knowing it would be illuminated later.
The boards and 'components' were painted with Vallejo acrylics, oil paint pens and metallic markers and real wiring was added where appropriate (yes, that is an electric shaver cord which is what was used for the originals!). I also sourced some images of the labels for the ICs online and printed them onto self-adhesive vinyl.
At this stage, I also attempted my first ever leather work(!) and patterned and made a holster for the main board, as well as a matching one for a PKE meter and several key fobs for the belt.
After a couple of false starts I got the correct diameter clear acrylic tubing for the 'Nixies' and cut it to size. To emulate the Nixies and to give some animation I hard-wired each 7-segment LED with a number and wired all 8 of them to a simple chaser circuit. My original concept was to have each LED run through a random sequence of numbers, but the sheer number of wires required and the complexity of the board to run 7 channels on each of 8 LEDs made me chicken out. My fall-back solution, which still gives the impression of a continuously-updating data stream at a cursory glance, only requires 2 wires from each LED and a single 8-channel board which can be hidden on the back of the fake board and run from a 9v battery. The 'E' has a single flashing red LED behind it and runs from the same battery. I had to shave the corner edges off the LEDs to fit them inside the tubes!
I think the finished result looks pretty good at a glance, and really adds to the overall look of the utility belt. As I said earlier, I think this is a really under-valued little prop and the original is a great example of using 'found objects' in an unfamiliar context to add detail, complexity and 'colour' to a costume. Thanks for reading!
And a short movie of the 'readout' animation...
In the first film, the main board component of the gizmos was the de-cased guts of a Sanyo ICC-808D calculator, while the daughter boards were each different and cobbled together from random electrical components. The most striking feature of the main boards was the array of 'Nixie tubes' at the top - numeric cathode displays that were the precursors of modern alpha-numeric LED displays (though these are never shown illuminated in the movie - at least not visibly).
In the second film, the gizmos were much cruder - literally painted dummy boards - and the Nixies were replaced with glass tubes containing a short length of rainbow ribbon cable!
I wanted to base my version on the more detailed first film gizmo. Of course, after nearly 40 years the original calculators are rare, and expensive when you find them. You can still get Nixie tubes - mainly from Eastern Europe - but they are usually a different style and, again, quite costly. For my purposes, I was quite content to settle for a final result that emulated the original props in appearance but without necessarily being completely accurate in every detail - especially given the generally ramshackle, hand-built and cobbled-together aspect of much of the Ghostbusters equipment.
In the end, I opted for 3D-printed resin boards and modern 7-segment LED displays inside lengths of clear, acrylic tube to mimic the Nixies. I also wanted to add a bit of animation and light-effects to the gizmo that was a bit more subtle than just flashing coloured LEDs - as if it was actually displaying some sort of data readout from the pack.
I found some quite nice affordable STLs on Cults3D by MrKiou and printed the various parts on my Elegoo Mars printer (I had to use Meshmixer to cut the main board into 3 pieces to fit it on the plate and then reassemble them later). I moulded and cast the 'E' display in red-tinted clear resin, knowing it would be illuminated later.
The boards and 'components' were painted with Vallejo acrylics, oil paint pens and metallic markers and real wiring was added where appropriate (yes, that is an electric shaver cord which is what was used for the originals!). I also sourced some images of the labels for the ICs online and printed them onto self-adhesive vinyl.
At this stage, I also attempted my first ever leather work(!) and patterned and made a holster for the main board, as well as a matching one for a PKE meter and several key fobs for the belt.
After a couple of false starts I got the correct diameter clear acrylic tubing for the 'Nixies' and cut it to size. To emulate the Nixies and to give some animation I hard-wired each 7-segment LED with a number and wired all 8 of them to a simple chaser circuit. My original concept was to have each LED run through a random sequence of numbers, but the sheer number of wires required and the complexity of the board to run 7 channels on each of 8 LEDs made me chicken out. My fall-back solution, which still gives the impression of a continuously-updating data stream at a cursory glance, only requires 2 wires from each LED and a single 8-channel board which can be hidden on the back of the fake board and run from a 9v battery. The 'E' has a single flashing red LED behind it and runs from the same battery. I had to shave the corner edges off the LEDs to fit them inside the tubes!
I think the finished result looks pretty good at a glance, and really adds to the overall look of the utility belt. As I said earlier, I think this is a really under-valued little prop and the original is a great example of using 'found objects' in an unfamiliar context to add detail, complexity and 'colour' to a costume. Thanks for reading!
And a short movie of the 'readout' animation...
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