More Steel Cutting, Sort of

I did spend a bit of time cutting some more steel this week, but unfortunately I fell ill early in the week. As a result, not a lot of information to post. I also discover that my original plan for supporting the back battery box won't work. I have to come up with a plan B and get a bit more steel. Now, excuse me while I go find some Sudafed.

Cutting Steel

Today I cut the steel to support the three battery boxes that will go in the engine compartment. I've been using a blade on my miter saw that is specifically for steel. As I was working, I came to realize that clearly the way to do this would be to use a torch. The only down sides I can think of are 1. I don't own a torch, and 2. it's conceivable that I would blow up myself and my house trying to learn. It would be a real bummer if my wife and kids came home to a cater. I think this is probably one of those things that you should be taught by someone who knows what they're doing.

Still, progress is good, and things are moving along. Next week, I'm hoping to finish the frame for the back battery box, weld up the frames, get them ready for paint and even put a coat or two on them.

Done With the Fuel Tank

Finally finished cutting the fuel tank out today. All the chunks above comprise about 75% of all the plastic that made up the tank. For those of you thinking I was crazy for doing it this way instead of the proper way, let me just say, you may be right. But, how long would it have taken one person without all the proper lifts, jacks, tools, etc. to remove the entire sub frame? This way ended up taking me about 5 1/2 to 6 hours. Man, did it suck though.

I'd really like to use all that vacated space for something. It would need to be something that I don't need to access regularly and can afford to be stuck away from the engine compartment. Right now the only thing that comes to mind is the DC/DC converter and perhaps the auxiliary battery. If I decide to put any electrical components in there, I'll have to build something to keep them dry and clean. Hmm... What to do...

Odds & Ends Part II

This last week has been spent doing a variety of things.

1. I've been working on removing the remnants of the gas tank, as promised. Loathsome, horrible work. Still, it's coming along.

2. Spent time measuring out and calculating how much 2/0 cable I'm going to be needing. I need to measure it out carefully because the stuff is $4.50/ft on a good day.

3. Worked on fitting the big battery box under the trunk. I have to work out how I'm going to suspend it from the frame and keep everything secure. This frame has to support just over 250 lbs of lead, so it better be up to the task.

4. While out looking for some steel to do #3, I happened to park near an automotive paint store. Though I knew I'd have to paint all the bare steel, I really hadn't given it much thought beyond picking up some spray paint at Lowes and going at it. I thought it would be nice if I could make most of the visible parts the same color as the car, but figured that would be too costly. On a whim, I stopped in and asked if there was anyway to paint some bits to match the car and not pay for a 1/2 gallon of paint, spray gun, etc. He said well I could put it in a standard "rattle can" for you. Apparently if you're in the biz, that's the lingo. I walked out with 2 cans of BMW Hellrot (Bright Red, for those of us who don't do German) for $14 a pop! I did get some primer and clear coat as well, but what a deal! This will help make things look real nice.

5. Look at the pretty sparks! Started measuring and cutting steel. I was hoping that the 10" abrasive wheel I got for my miter saw would do the trick, but no such luck. It cut through a couple of pieces then just stopped cutting. It would seem their claims that it cuts metal are a bit over stated. Looks like I'm going to have to buy a real steel cutting blade.

Behold the boxy goodness!

After a lot of thought and consideration, I decided to go with plastic for the battery boxes. They are made from 1/4" thick polypropylene plastic, welded at the seams. They will not corrode and will contain any acid spill that may come their way. Plus they are nice and lite.

There's room for 11 group 31 batteries in them there boxes. I'll be using 12 volt Crown deep cycle batteries, for a total of 132 VDC and approximately 18.5 KW of juice. Of course I'm going to have to build a steel support structure to hold them in place, and devise a way to hold the batteries firmly inside the boxes so pot holes and the speed humps in my neighborhood don't send them flying. Details.

Next up, I have to finish cutting the fuel tank out. I've been putting it off or working on other things because it is teh suck! But it has to be done.

Instrument Cluster

One of the things that truly does worry me about all this is how to make all the instruments work. The Zilla controller will run the tachometer, IF I can isolate the leads to it, figure out what each one is and plug them in to the hairball correctly. The Zilla can also use the "Check Engine"light (or any other unused light for that matter) to warn of system faults, again IF I can figure it out.

The tough one is going to be the speedometer. The sensor for the speedo is in the trans axle. It sends a signal to the ECU (Electronic Control Unit, the car's computer) which in turn sends a signal to the instrument cluster. Well, the ECU is effectively dead. At least I think so. It's still there, but of the 6 wiring harnesses that were plugged into it, all but one is gone. My hopes that the one remaining cluster of wires contains both the lead in and out for the speedo, AND the unit will work as designed with no input from an engine are slim.

I may end up having to build something that processes and sends the correct signal to the instrument. Stop laughing! Yeah, I'm not so sure I can do it either. I may be left with no other choice than to use an after market speedo. I think you can see why this part worries me.

Front Battery Boxes

It occurred to me that I'd better start solving any problems with fitting batteries in the front end. I spent some time building some cardboard trays that would hold the cardboard batteries I built. All the cardboard mock ups that I made are carefully built to match the actual size of the batteries I intend to use. I'm planning on using 11 Crown 31D36 12V batteries, for a total of 132 VDC and approximately 18.5 KWh. Originally I wanted to use 14, but there simply wasn't anyway to accomplish that.

As you can see, I'll be able to fit 7 batteries up front quite easily. Under the front battery box is plenty of room for the accessories I'm going to use, A/C system and power steering pump and vacuum pump for the brakes. The three batteries back by the firewall will end up being about the same height as the two directly in front, I just couldn't find anything to hold them up there. Eventually, there will be some pretty substantial bracing to hold them up.

I haven't decided what to make the actual battery boxes, or trays out of. Fiberglass is out, not enough room. As I see it, I could use steel or carbon fiber. They measure up like this. Steel is cheap, but heavy. Carbon fiber is light, but decidedly not cheap. I have a few weeks to decide.