OK, lets build a scooter....

[pipedope]

Here is what I was looking at;

quote: Aquamaniac once bubbled...


The Mako motor specs are
Speed:2.7 Mph
Thrust: 50lbs
Voltage: 24 VDC
Current: 34 Amps
Power: ~800 watts

Dave


Dear Dave,

The Mako motor does 800RPM,
at 24VDC using an average of 10A.
The tuned motors George is now using turn at up to 1200RPM, burn @ 17A at 24V and produce 55LBS of thrust. The propblades have to be pinned for the higher thrust otherwise they will bend/warp.


There are the nameplate specs for the Mako and then a jump to average numbers without detail of the conditions of the tests.

The wind of the motor will determine where the 'sweet spot' is.
Will the motor want to turn fast with low torque or slow with high torque. Picking the right frame and wind is important as they need to match the load of the prop. The prop needs to match to thrust needed to pull the load.
The idea combination will be different for a rec diver with a single tank and a deep tech diver with twins and stages.

It is helpfull to look at the entire system including the diver and gear. Much like setting up a power boat. A light speed boat will use a small prop turning at high speed. A tug will have a very large, slow turning screw. Most boats are somewhere in between.

Getting something to work is pretty easy. Getting both performance and efficiency is not so easy.

 

[Scuba_Vixen]

from known values, you can fill in the unknowns.

Typical batteries for the tekna/mako are 18 to 20ah (20 hr rate) and only 10 to 12 ah (when looking at their 1hr rate.... (the realistic one for this application)

Most rec divers get close to an hour (give or take, depending on conditions) of run time, before the battery seems tired.

That tells us that the motor draws about 10 to 12 amps on average.

If you get less than an hour, you can look at the battery spec sheets and get a close approximation of draw for the conditions that gave less burn time.

I'm thinking that maybe the 34 amp figure was for locked rotor amps .... fair sized 12v trolling motors are less than 35 amps.

Just can't resist a scooter thread,

Darlene

 

[pipedope]

May I move in with you and build scooters?