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by JKCalhoun 893 days ago
It reminds me of an obsession I had when I was young (maybe 12 or 13) where I kept iterating on a design for a mini-sub I had hoped to build. I must have checked out books on the history of the submarine about that time and became obsessed with the simplicity of the original Turtle submarine — operated with hand screws (propellers).

Likely too I saw a homemade sub or scuba tow on the odd Popular Mechanics cover....

I had read enough to incorporate a lead ballast that could be released from inside the sub. I imagined props and motors based around those electric trolling motors you can get for a small fishing boat. I therefore incorporated a car battery into the design. Front and rear ballast tanks allowed me to control the pitch trim. I imagined a small electric automotive tire pump would suffice to force the water out of the ballast tanks.

I obsessed over a mechanism to allow each trolling motor to be gimbaled from a pair of joysticks in the sub. I built mechanical models with paper drinking straws and toilet paper rolls to test the mechanics.

I played with different seating configurations to minimize the size of the sub but keep it "operatable".

It was a weird and impossible fantasy that never had a chance of moving beyond the drawing board stage. You know, especially for a kid with a single mother who was a secretary. But perhaps there was some intellectual and creative stimulation that I was feeding off at the time that made the effort worth it.

Thinking about it now though, how obsessive I was, it might also have spoke to a boredom, isolation and maybe sadness I felt at the time. The sub might have been an escape for me.

To see someone build a sub for real is kind of cool. But it also makes clear how likely my design would have just collapsed right away at about 10 feet depth. I mean, I planned on using plywood for the hull, ha ha.

11 comments

Oh man, that's great! For me it was a go-kart. They were illegal where I lived (Chicago suburbs), but whatever.

There were two big hurdles for a kid: acquisition of a side-shaft motor (lawn mower engines' shafts were vertical, so no dice) and acquisition of a clutch. I couldn't afford either of those. Nor could I weld.

My friend and neighbor, as it turns out, inexplicably had a snow-blower engine in his garage. Horizontal shaft, perfect! But I still couldn't get a clutch.

So I decided who needs to start or stop in a sane manner? I'd simply attach a bicycle wheel directly to the shaft of the engine, and use lawn-mower wheels for the other three.

Then I set about to build the frame, by hacksawing an old angle-iron bed frame apart and bolting it into a rectangle. I managed to cut the metal, but drilling holes in it for bolts proved to be essentially impossible.

So I built a crude platform out of wood and attached the wheels to it. The front wheels were bolted onto the ends of a board that I could pivot with my feet. Then I bolted the engine onto the back, with wood shims to make the bicycle wheel meet the ground at the same height as the three other wheels.

There were no brakes and no way to totally stop the engine. I propped the back up on some bricks and went to start it... and the pull-start mechanism broke. Probably saved me from serious injury or worse.

And that was that.

To be fair, I raced 2-stroke karts for years, and up until relatively recently, clutches weren't a thing. Most karts were direct-drive, as you didn't want lag and power loss, and simplicity was usually more important than anything else for weight and general sanity. The engine was more likely to stall when you didn't want it to than go when it shouldn't - if you spun in a race, that was it, race over.

That said, the rest of your kart sounds like it was probably best avoided - you should be grateful for that pull-start breakage, yes!

Interesting! This was long before the Internet, so all I had to go on was books I checked out from the library about how to build stuff. They presented the clutch as a basic component.

The other topic I repeatedly checked books out on was movie special effects. Of course I wanted to make "laser beams" in my Super-8 movies. This, not surprisingly, was even less practical than a go-kart because it required an optical printer. Books offered the idea of drawing on or scratching the film as an alternative, but even as a kid I rejected that as utterly impractical and lame on a tiny 8mm frame.

I did make a bunch of movies, and do and build cool stuff as a kid. I wonder how much more I would have accomplished with access to all the info and 3-D printers and video capability kids have today. Would I do more because of all that, or less because of the massive distraction of the media now?

That last question is one I think about often! It sounds like your childhood was pretty well spent. I wanted to make lasers too - just not on film! I built most of one, but only lacked a decently sized ruby, for some reason. Probably just as well, as my childhood electronics would almost certainly have been at least as lethal as your kart...
To an eyeball or two, at least!
the one time i went out on an open wheel shifter kart i recall bump starting it and power shifting, but indeed no clutch.
It turns out the John Mayer of all people wrote a (imho) really beautiful song about a man building a homemade submarine in his basement, called "Walt Grace's Submarine Test, January 1967". If you feel like taking a listen, it might stir up some memories; I know that I usually connect with it more after a weekend of getting lost in a passion project.

[1] https://www.youtube.com/watch?v=SrcMMyNeJJs

Similarly, Resistor recorded a good progressive rock album called To The Stars, about a boy who builds a rocket ship in his backyard.

https://resistor222.bandcamp.com/album/to-the-stars

https://www.youtube.com/watch?v=Fm6WMMgmMpM

> I mean, I planned on using plywood for the hull, ha ha.

https://www.svseeker.com/argonaut-jr-building-and-diving-a-w... (“Argonaut Jr – Building and Diving a Wooden Submarine from 1894”)

Very cool, had not seen. I am that guy!
Both the replica and the original are totally amazing! I expected something impractical.
When I was 7, with a bunch of friends, I built a 'plane' in our attic. We went all over the globe with it looking for treasure ;) It's funny because until your comment I had totally forgotten about it but now I remember the cables that moved the ailerons, and the two old car seats for pilot and co-pilot (or passenger...). Some magazine (Panorama?) had printed a treasure map and even though the magazine itself was strictly off limits to us the father of one of my friends had donated the map to our cause which we kept as our most precious secret.
Plywood sounds great! It is used in boat Buildng all the time.(aircraft also) By bending very thin(1/8” for example), you can add by gluing, and or nailing each later on top, which will hold the original bent shape. Plywood itself is strong, because of it's intrinsic layers, and adding more layers on top, makes it extremely strong. Making the bow and Stern, fit and be as tight and strong - that's another problem. Maybe you should get back to the drawing board, and continue. Sounds like a great project.
I had very similar flights of fancy as well. Some combination of low-tech, soapbox-derby materials and a wild idea that I could build a raft out of 2x4s and cross the lake! Or make a parachute out of a pillowcase! Or put wings on my bike and fly!

I’d doodle designs and look at piles of junk, imagining what I could do with the materials.

I think the appeal was partly that the proper materials were way out of reach for me, and if my terrible idea failed, it was just made out of everyday stuff anyway.

Hopelessly impractical and (as you say) a bit obsessive.

Man, I went through the same thing with dirigibles when I was a kid. Never gonna be able to afford a blimp hangar though...
>I planned on using plywood for the hull

Reminds me of the guys that entered a robot with MDF 'armour' for Robot Wars. You can imagine how well that went! ;0)

If you can't imagine it, see: https://robotwars.fandom.com/wiki/Overdozer https://www.youtube.com/watch?v=395VuP374HE (BTW I wouldn't call them 'idiots'. Kudos to them for having a go.)

> It reminds me of an obsession I had when I was young (maybe 12 or 13) where I kept iterating on a design for a mini-sub I had hoped to build.

I don’t know when that was, but nowadays it is feasible, for a kid [0]. Not sure how deep it can go though.

[0]: https://youtube.com/watch?v=KLEH8RJsYgI

Yes but what an amazing 10-foot journey that would have been!
Thanks for sharing, your story is great : - )