Monday, June 23, 2008

How to Cut Myself - Let Me Count the Ways

June 16 – June 22, 2008

They say that “chicks dig scars”, so I must be a real chick magnet. I doesn’t matter what I do, working on this car has my arms, shoulders, face, legs and ankles (ouch) are battered, cut and bruised. That one bolt or nut is always in the worst spot to get to, but I will not be deterred – no matter how many times I bleed. So if your love life is lacking, just do a EV conversion and it will dramatically improve (those ER nurses won’t stay away). And just so you don’t think I’m some male, chauvinistic pig, us guys dig a scar or two ourselves. Heck, my wife just had a little wrist surgery and I can’t keep my hands off from her!

On to the car…

The battery boxes are in (the out, then in). The very front box (holds three) I figured would be a piece of cake. It sits between the frame rails and had just eight holes to drill. After a bit of cussing and discussing, it went in. After trying it with my battery models I had to figure out how to get the real batteries in – a bit of a tight fit. Next came the other front rack (a day later). Since this one was supported on the frame rails, I decided two bolts were enough. One bolt went into an abandoned hole from something I removed (already threaded and I found the old bolt!), but the other went into the frame rail itself. I wanted to hit a flange that was on top to avoid trying to get a nut and washer inside of the frame rail. I succeeded, but the hole ended up in a place that required a contortionist with three arms to get to. I only had to remove this rack once after I installed it. Next to the back where the rack above the motor was first. I did a lot of guessing when I built this rack. I knew where I wanted it to go, but it had a mind of its own. This is also the biggest rack – a four holer. When I tried to get it in, I actually did a great job of getting it stuck. I refused to undo the transmission cables, so I exercised my right to mumble a few choice words, got out the crowbar, and unstuck the beast. Reality set in and I got out the Saws-all. I figured it was safe to cut two of the braces in half and just reposition them. I got it to fit, drilled a couple of holes and marked to for welding. Once welded, it went right in. Then I noticed that one corner was unsupported, so back to the shop – it was a quick fix. As a soapbox moment, better safe than sorry. Batteries weigh a lot folks and to hit a bump and have them come crashing down, it’s worth the extra effort (and time) to do it right to avoid this from happening. If you are at a crossroads of “just git ‘er done” or doing it right, take the high road. Plus I can guarantee you that if it fails, it will damage the most expensive part – I’m off of my soapbox. With box number three repainted and ready to go, I went for the last one – a two spot in the old rear trunk. I really wanted to put the spare in the trunk, so I cut a piece of the frame off. I wasn’t structural, so I figured it was worth a try – it didn’t work, but I did save a pound or two. This rack was getting two bolts. It is supported by frame members on each end and part of the trunk lip along one side. I just had to hit the frame in the same way I did the front box. The hole ended up in a tiny corner that I could only reach with a 12” ratchet extension. I quickly got a nut and lock washer on it and moved on.

With all four racks in (and out and in) it was time to get the batteries. Getting those old batteries for cores was great - it saved me over $100. The final bill for my 12 Deka 9A31 AGM Intimidators was just over $1800. Part of the Belktronix system is a battery management system (BMS) that is integrated with the charger. Each battery has both overcharge protection and a temperature sensor. I plan on doing a religious job of breaking in my pack and taking good care of them overall. The death of many EV’s is the battery pack. Discharging them too deep and too often, over (or under) charging them and in general abusing them will kill a pack. In an overly optimistic way I am hoping to get 5-6 years out of this pack, but 4 would be great. There are tales of some folks doing this and I want to be part of the legend. And at $1800, I want to squeeze every once of life I can get from them. A BMS is the way to go and it is something you should investigate.

With batteries in hand (all 850 lbs or so), it was time to fill up those racks. I started in the front again (lots of good places to cut myself) and filled the front rack. I use a product called Coro-Plas (corrugated plastic) to line my boxes. It’s tough stuff and provides a cushion on the bottom and well as in between. I made the boxes slightly oversized to let me use the Coro-Plas and it also allows me to get everything nice and snug. Again, you don’t want these batteries moving around. One rack down, one to go (front only today). A week or two ago I was removing stuff up front when I pulled out a sensor from the heater area. I stuck in my parts box and forgot about it. Before I put the batteries in, I realized I need to put it back. I saw a few leaf bits in the hole and got out the Shop-Vac. One bit led to another and before you know it I had the entire blower system removed. It gave me a chance to get the rest of the unneeded A/C stuff out and the whole pile of leaves that were in there. Rack two was filled when I realized the terminals were not working out the way I wanted them to. The front six batteries are getting linked to the rear six to make up my 144V pack (by way of two 2/0 cables). I wanted to have a positive and negative terminal close to each other to make it easier to run these cables. Those nice and tightly fitted batteries in the lower box had to be switched around. Thank God I removed my hood from the car before I started or it would have been near impossible to get that one battery turned around. With everything in order, I got the other three batteries in place and packed with Coro-Plas. Adding over 400 lbs to the front of the car certainly lowered it. There is still a little spring left in the front springs, so I don’t think I have bottomed out yet. I will have to wait until I get a chance to drive it before I see if bigger springs (or air shocks) are needed. I am going to wait on the wiring until I get everything ready – having 72V (or 144V) just waiting to zap me is a scary thought. I one time arc welded a Seiko watchband (while on my wrist) across two alternator terminals at about 14V – 144V would really hurt (but just think of the scar).

In the back I had some old ICE wiring to deal with before putting in the batteries. For now I am zip tying them up just to get them out of the way. I figure that if I need something later, it would be easier to deal with still intact. But just to make the back of the car less jealous, I made up my jumper cable for my motor. That pretty, green 2/0 cable across the A1 and S1 terminals is just the start to the wiring nightmare that awaits me, so I better get some sleep. So until next week….


DRBushee said...

not quite sure i understand the idea of cutting a hex plate out and then welding it back in. perhaps a few words of expalnation. it looks like the outside shape will bolt to the bellhouising of the tranny.

EL (Electric) Fiero said...

The purpose of the hexagon was to make welding it easier. It could have been a circle, but that would have required me to bend a circular spacer. I had some 2" x 1/4" flat stock and it required no bending, just cutting. Hope this answers your question.