Friday, February 15, 2008

The project vehicle

I want an EV. I like the idea of an electric powered vehicle, for many reasons, but for this project the main reasons are I'd like to drive around the woods and haul firewood without a lot of noise and without driving in a cloud of smoke. My situation also called for water crossing capabilities, good traction for climbing hills, and low end power for hauling wood. After considering 4 wheelers and not feeling they were up to my needs I remembered 6x6's such as Max, Argo, and Attex, also known as AATV's and 6 Wheelers. After searching around I found this baby.
Behold, the Attex!


It's a 6 wheel drive, amphibious vehicle, probably mid 1970's vintage, skid steer, 2 stroke powered, and lots of fun! However, because of the 2 stroke it's loud, smelly, polluting, and has a narrow powerband that doesn't come into play until you rev the motor up and get the ramp clutches going. That's fine for steady high speed but not great for low end torque and slow speed maneuvering, which is what I need.

Here is the solution.
A 7.5 inch Yale forklift motor modified by Jim Husted of HiTorqueElectric.com



An electric motor fits the bill perfectly. No noise and smoke, full torque from 1 rpm, no gas to buy, no spark plugs or oil to change, and I can charge it up for pennies, even fewer pennies if I put a timer on it and charge it at the night rate, which I will do. Interestingly Attex actually made an electric version of the 6x6 back in the early 70's, so I'm not really doing anything new. They ran theirs with 6 12 volt batteries at 36 volts, I'll be running mine with 4 12 volts at 48 volts. I'll have a lighter vehicle with more power but a shorter run time, which will be fine for my situation. Someday if Lithium batteries get cheaper I can increase both power and range while reducing the weight as well.
At this stage I've pulled the old motor and gas tank and have started designing the new motor mounts and battery brackets.
Costs so far:
Attex $1100.00
7.5 inch Yale motor from HiTorqueElectric $550.00 (inc. shipping)
Alltrax AXE 4845 Controller (Used) From evdrives.com $320.00 (inc. shipping)

Still to come:
4 AGM batteries, probably around $720.00
Charger $280.00
Contactor $65.00
Chain and sprockets around $70.00
Throttle, cable, diode, resistor, etc. $35.00
Battery cables and terminals? $50.00
Projected total so far $3190.00 (Updated cost)
Sold old motor for $150.00 -
Total $3040.00

I'm sure it will increase but it should stay under $3500.00 when finished, which is about what I was looking at for a good used 4x4, which couldn't float.
Still a lot to do but I can't wait to drive this thing as an EV!

John

7 comments:

Mike said...

I can't wait to see this 6x6 come to life. I want to see a video of it coming towards the camera where all that you hear is the wind as you pass by :D

John said...

Hopefully soon :D

Thalass said...

This is an awesome project. My father in law has something similar to this, maybe I can convince him to let me hack into it one day!

Question, though, couldn't you go with two motors? One for the left ad one for the right. Two smaller ones would give you more or less the same power, but would give you better control than skid-steering. It'd be a more complicated conversion, though.

Anonymous said...

I found 4 AGM batteries for my ATV EV for 129. each, I think they were 53 pounds each. They were 12v at 75AH

Anonymous said...

The 12 volt 75 AH batts were universal batteries from apex battery and free ship over 50.00

elevatorguy

Anonymous said...

thalass,
Yes, I could use 2 motors, but as you said it becomes much more complicated, and more expensive. They'd have to be capable of regen to get the skid steering through motor braking, or I'd have to rig a separate brake system for each side.
Elevatorguy,
The Oddyssey's I'm looking at are supposed to be superior to the UB's. They claim a longer lifespan and higher output as well as faster charging capabilities.

John

Thalass said...

Ah that's a point, I didn't think of the motors needing regen. You probably have it right how it is. I'll keep an eye on this project :)