I finished the first production version, and I am pleased with how it's turned out (pics to be loaded tonight). It looks the same as the prototype mule, but it has steel nutserts instead of tapped threads in the aluminum. Also, all the bolts now use a 5mm hex-wrench. Most of the bolts are M6 (very close in size to 1/4"), and the center bolt in the sliding slot is a larger M8-bolt, but I found an M8 that still uses a 5mm wrench.
The stems bar-cap uses bolts that require a 4mm hex-wrench, but once I tighten them down onto the cross-tube with a dab of lock-tite, they never need to be wrenched. All that is needed to attach and adjust everything on the drive is a 5mm hex-wrench.
A thought recently ocurred to me, I was wondering if anyone here would like to buy one of these? My focus has been on developing this with an eye towards selling a few units to the local college students. I have a full-time job, but I could easily make one unit per week-end.
I have also taken efforts to fully disclose every stage of the build with details and pics, so that anyone else who wants to build one of these, can make one while avoiding my R&D stumbles.
I've ordered a throttle kit from Matt that incorporates his new improvements, but AJs report on them was so positive, many other people ordered one too! Matts existing shelf stock and parts bin were cleaned out, and to make a throttle for me, he had to order more parts. I should be getting it soon, but to be frank, I have not driven my drive at all! so it is still in the experimental stage.
I have an extra drive sitting in front of me right now, but I would have to order a motor for it (your choice of available kVs) and once arrived, I would have to shorten the shaft 1/3rd of an inch and also cut two parallel flats on the shaft sides. Once thats done, and fitted, I could ship the drive.
I can also make any part of the drive as a separate piece, such as the 1.0" diameter roller with two one-way clutch-bearings, and also an optional 1-1/4" diameter (they both slide onto a 1/2" diameter case-hardened shaft). I hope to find a knurled-steel roller solution within a few months, but I can't guarantee if that will happen, so for now I am using the sticky-backed sandpaper, just as the Kepler-drives are using. I'm told it does wear out occasionally, but it is available and cheap when it needs to be replaced.
If there is any interest, I will start a sale thread and calculate the costs. My thanks to everyone, for all the generous help and advice I have recieved.
edit: I have recieved PMs of interest, so I will put together a sale-thread for the "new items for sale" section, and link it here to make it easy to re-find later. Also, I have started a sale-thread for the rollers by themselves for experimenters:http://endless-sphere.com/forums/viewtopic.php?f=31&t=23089