DIY Scooter

[=C=]

Hi all,

I flipped thru the DIY forums and didnt see anything on scooters. I'm at the very start of this project and was thinking of using some parts from this scooter place as they seem to have a variety of batteries and 12/24v motors.

The specificatios for the scooter I'd like to build are as follows:
Max Depth: 120ft
Shell: Aluminium
Voltage: 24v
Burn time: 80min
Max Speed: 4kts

I would like to keep the diameter small so I can rely on the housing material for strenght and also so I dont have far to transmit heat from the motor. Looking around the net scooters usually have large diameter housings when the motor and batteries are very narrow. It seems from a hydrodynamic standpoint a narrower profile would be more efficent. Anyone know why that is?

I dont suppose anyone has a website o rthe math to calculate burntime on Batteries.

 

[divebostonforcharity]

Try doing a search. I know I've seen a bunch of DIY scooter stuff somewhere on ScubaBoards.

 

[marchand]

you don't want to make the shell out of aluminum. you want this thing to be as light as possible. Honestly, it will be cheaper to buy an old mako than to build your own scooter.

 

[Mr.X]

There was a fella named Dagodiver who created his own Gavin-style scooter. He is a member of the Decostop. I believe he had access to CNC milling equipment and he did a spectacular job as a skilled machinist.

X

 

[marchand]

One reason why scooters like the UV26 have a large diameter housing is because they need to displace a large amount of water in order to be neutral. I believe the UV26 weighs in at ~90lbs, and the batteries are anything but narrow.

Making a housing out of aluminum would only serve to make the scooter heavier, which means slower and it needs to displace more water to be neutral. Do yourself a favor and make it out of an extruded thermoplastic tube.

If you are going to build a scooter you should save yourself some grief and make it right the first time. Don't be cheap, this will cost you more in the long run.

Try to buy a dead mako for cheap and take the a$$ end off of it and use that to build off of. That way you have a good clutch, nine speed settings, and a good propeller. I can guarantee that you don't want to make everything from scratch; water proofing a propeller shaft is not easy and you do not want to use O-rings for that.

For batteries I would either use SLA or lithium iron oxide batteries. SLA if you are trying to keep the up front cost down, LiFePO4 if you never want to replace them.

Heat distribution is really a non issue.

If you have access to a full machine shop and are a good machinist then go for it, if not you are better off buying used.