February 2011

I wonder if it’s even possible to spot weld aluminum with my spot welder? It is not as conductive as copper, but is far less expensive. Copper has at least tripled in the last couple of years. So I will start with trying to spot weld some aluminum foil from the kitchen and see how that goes. It’s cheap and easy to use for proving the concept, one way or the other. I will still be trying to spot weld braid as well.

Today I found a shop that actually could handle the shims on my front end. My normal alignment shop sent me to them.

I had the service writer write down what I wanted. Zero toe and zero camber. When they were done it was R+.125 L+.50. with me in the truck. The manager told me my body weight will change the camber .25 degrees. I didn’t buy it. When he took the measurements with me in and out, they changed .125 degrees. Which made more sense. Then I mentioned that +.5 is a far cry from zero. So they did the left side again. Now it’s R+.125 and Lzero with me not in the truck. With me in the truck it’s Rzero and L+.125. Much better! Splitting .125 degrees is very fine, but I wanted zero camber while rolling down the road. They started out at +1 and +1.25. It’s raining like mad here. When it’s clear I’ll see how it feels. Initially it’s fine and stops dead straight without using any regen. $100 however. But after the wear I found on my front tires, it would have worth doing it 16k miles ago. I did have it aligned back then, but the previous shop didn’t want to go after the hard to get shims. They accessed the shims today from the tire opening. So the Dolphin didn’t really matter.

After the test drives they had taken on my truck, it had used 400wh/mi! That’s what I use to get with my 104 Hawker lead pack! It’s usually around 225-250wh/mi.

Starting last night I drove the pack down until it was only around 200v. Then pulled it into the garage for discharge maintenance. I made up a system using six 2000w, 120vac water heater elements to discharge the pack in large groups rather than just two groups.

Here is the pack attached to all of the water heater elements. A 5 gallon bucket of water was used for cooling since an experiment with air cooling caused the elements to glow red, which is an ignition source. The water level dropped about 3/4″ when the pack was done discharging.

I used my cnc to machine 6 holes in these two pieces of 3/8″ thick plywood. They held the heater elements 3″ apart and 3″ from the sides of the plastic bucket.

After the overnight discharge was complete, I put some jumpers across about 5 cells that were still showing some voltage (not shown). Shown here is the 240vac variac and a bridge rectifier mounted to it’s heat sink. It takes me about 45 minutes raising the voltage by hand, to about 320vdc. After that, the on board charger is used to finish up the charging.

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