Wow, who’d have thought — some folks are actually irritated that I haven’t updated in a while. I’ll interpret that as good news, that I’m not just typing this for myself; maybe I’ll now feel more pressure to update it more often, which can only be a good thing. While not going into too much detail, there has been a lot going on for me in recent months, not all of it good. My apologies for the lapse.

Fortunately, it hasn’t been for lack of events with the project. Despite my earlier hopes, these days I still have almost no time to work on the project during the week, but I’ve set aside every Saturday afternoon from 2 to 4, and so at least every week sees some work done. Currently, the only thing left on the truck to be disassembled is the dash, to replace the heater core with a ceramic PTC element (e.g. from a $20 Wal-Mart space heater). Everything besides that is stripped down; the interior is even stripped to the sheet metal. The engine is out, the fuel and exhaust components are out, and this past weekend I built a size-accurate mockup of the motor to help with figuring out how I’m going to mount it. Pictures of all of this are forthcoming; I’ll add to this post or follow it up when I’ve got them on the server.

I can’t finish without some pics however — these taken by the folks at Netgain of a motor nearly identical to mine, produced for another customer. This shot shows the motor next to the Impulse 8, which looks like a golf cart motor in comparison. Another shows the six terminals, to allow series/parallel switching of the split field. The wire coil is from the overtemp switch, which can be used to tell the controller that the motor is overheating. This picture shows the drive end fitted with a yoke for a 1350 U-joint. I’ve been told that the customer intends to weld this yoke in place and use a telescoping driveshaft from a 4×4 to deal with suspension travel. I have different plans.

And that brings me to my favorite pictures, of the custom-machined 8620 chrome-moly shaft from the awesome folks at Dutchman Motorsports. Like the motor it’s designed for, this thing is a beast — that’s a sixteen-inch ruler there folks. The real challenge in making a part like this is the hardening process. When you heat-treat steel to harden it, you find that afterward, it’s changed shape slightly. So the manufacturing process ends up having 3 phases — milling to spec, hardening, and then milling again. Except that the second time, you can’t really mill it with cutters anymore; you’d ruin your tools. So you have to grind it. Really challenging work, unless you’re an expert like the Dutchman. The dimensional tolerance on nearly all the dimensions of this part was 2 thousandths of an inch. The finished part is accurate to within 1 thousandth.

If the Warp13 is truly “Torque City” as reportedly exclaimed by an impressed Warfield engineer, this shaft will provide a nice 6-lane highway out of it.

In case you’re curious, the other shaft in the pictures is one that another customer had made for a smaller (but still huge) Warp11 motor; apparently he arrived at the same conclusion I did and went for a custom job. His shaft was made by Mark Williams — some pretty esteemed company for mine to have in these photos.

So, the motor adventure continues. It’s been right at six months since I paid Mark Klemkosky at Matches Motors for my Warp 13 motor; little did he, I, or Netgain know at that point how much of a hassle my order would end up being. And yesterday, I got a call, the gist of which is that I’m going to have to provide part of it myself.

After weeks of going back and forth between Mark, and George at Netgain with my unusual requirements, I started dealing with Netgain more directly. Bouts of email correspondence would trail off into nothing for a month or two, then a report of more problems or protests from Netgain and/or Warfield engineers would arrive, complaining that the design won’t work for one reason or another. The original plan seemed very simple to me, but then I suppose most wrongheaded ideas probably do to those like me who aren’t knowledgeable enough to understand.

What I wanted to do was simply mill a spline on the motor shaft, and put a slip yoke on it to attach directly to a driveshaft going to the rear differential. The yoke would slip on the motor shaft as if it were a transmission output shaft, and the minimum of parts would help keep the whole setup lightweight, strong, and vibration free. Unfortunately, things are not going to be this simple. First of all, with the level of torque I’m expecting from this motor, I believe the only choice for a shaft material is either a hardened chrome-moly like 8620 or 9310, or a hard stainless which might not end up as tough but would be easier to manufacture since it wouldn’t need to be hardened. For whatever reason, this has presented a major problem for Netgain, who cannot make the shaft from anything but 1144 “Stressproof” which is a weaker low-carbon steel. It’s fine for industrial motors, but it’d have to be well over 3″ thick to handle the torque I believe this motor will produce, and all we have on the output is 1.37″.

Well, the final word arrived yesterday. I can do what I’m wanting to do, but I’m going to have to provide them with a shaft. They’ve mailed me the engineering drawings of the shaft dimensions the motor requires, and I will take the drawings to a machinist. I’ll then ship the completed shaft to them and they can then assemble the motor.

I have no idea how much it will cost, but I’m guessing it will be several hundred dollars. I hope it’s not in the 4-digit range; sadly I don’t even know if that’s a reasonable fear.

Beyond all that though, as I said to George I can’t really complain too much here. I’m not buying a normal motor, and I’m not using it in a normal conversion. I didn’t expect I’d get my motor quickly, and since I’m not really even ready for it yet, I’m not bothered too much by how long this is taking. I’m glad I didn’t put off the decision to buy the motor until I needed it.