Building your own scooter?

[Eric Sedletzky]

I’m thinking of building my own scooter. Has anyone here done this?
I was thinking of using an electric trolling motor, a multi directional sealed marine battery and build the housing out of fiberglass, which I have done a lot of (building plugs, casting molds, and finally casting finished parts). The controls might be a challenge but I could figure out a way to turn the handle controls into thumb controls on the handle.
I could also use aluminum since I can TIG weld it together, or a multitude of materials. I don’t care how heavy it is, I just want a lot of power and a lot of range. This would be for open ocean diving off beaches in Northern California.
And I have more time than money. I’m not shelling out 5K+ for a pro level scooter.

 

[Nemrod]

I’m thinking of building my own scooter. Has anyone here done this?
I was thinking of using an electric trolling motor, a multi directional sealed marine battery and build the housing out of fiberglass, which I have done a lot of (building plugs, casting molds, and finally casting finished parts). The controls might be a challenge but I could figure out a way to turn the handle controls into thumb controls on the handle.
I could also use aluminum since I can TIG weld it together, or a multitude of materials. I don’t care how heavy it is, I just want a lot of power and a lot of range. This would be for open ocean diving off beaches in Northern California.
And I have more time than money. I’m not shelling out 5K+ for a pro level scooter.

I built one using plans from Popular Science. I also tried to make a UW gill from such plans. The scooter worked, the gills did not. The scooter used a Shakespere trolling motor. I was a teenager and it did fine for the depths I dived at the time. I still have one of the plans sets (somewhere).

Then I owned a bunch of Tekna scooters.

James

 

[Akimbo]

FRP (Fiber-Reinforced Plastic) isn't a great choice for external pressure vessels/housings. Pressure testing once is not a reliable indicator of safe max depth rating because it is not a homogenous material like Aluminum.

The problem is an implosion of such a large housing would be devastating. I met a guy in the 1960s that lost fingers when a small Plexiglas (Leica) camera housing imploded in his hands, I don't know the depth.

 

[Nemrod]

FRP (Fiber-Reinforced Plastic) isn't a great choice for external pressure vessels/housings. Pressure testing once is not a reliable indicator of safe max depth rating because it is not a homogenous material like Aluminum.

The problem is an implosion of such a large housing would be devastating. I met a guy in the 1960s that lost fingers when a small Plexiglas (Leica) camera housing imploded in his hands, I don't know the depth.

The scooter plans I used to build mine specified an aluminum tube. The bulkheads were ply. The forward cone and aft cone were hard balsa and fiberglassed. PVC is probably what I would use today or even commercially available CF tube. Trolling motors are not intended for submergence at great depth and will likely eventually leak. Mine never leaked but I never took it deeper than 60 feet if that. Battery technology has so advanced and so have e-motors with electronic controls that what I built was like stoneage.

I used an earlier version of this plan set:

 

[Eric Sedletzky]

FRP (Fiber-Reinforced Plastic) isn't a great choice for external pressure vessels/housings. Pressure testing once is not a reliable indicator of safe max depth rating because it is not a homogenous material like Aluminum.

The problem is an implosion of such a large housing would be devastating. I met a guy in the 1960s that lost fingers when a small Plexiglas (Leica) camera housing imploded in his hands, I don't know the depth.

I depends on how thick and the shape too. Any surface that’s flat will suffer worse than a shape that is convex. Make it look like a bomb.
Also, minimize the internal cavity and design it so the battery compartment is minimal with minimal air space.
I would consider using vinyl ester resin and C-cloth which is used for missile nose cones. No matting.
I wouldn’t take it very deep either, about 100’ max.

 

[happy-diver]

Ha ha ha ha ha

Protei-5 DPV

Give Dave a shout out on arsebook

 

[JohnN]

Ha ha ha ha ha

Protei-5 DPV

Give Dave a shout out on arsebook

Way cool: Protei-5 Russian diver propulsion vehicle - Wikipedia

 

[Giselle]

@Eric Sedletzky I'm curious to know how the project is coming along. I'm just started looking at my options with scooters.

 

[runsongas]

unless if you have a lot of time on your hands, refurbing a farallon or just buying a blacktip is likely more efficient

 

[Eric Sedletzky]

@Eric Sedletzky I'm curious to know how the project is coming along. I'm just started looking at my options with scooters.

It’s not.
Your plate comes first.