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You know Esjaavik brings up a good point. When these plans are finished and confirmed a success. They could be sold at non-profit levels, on a CD containing every thing from cad drawings to free full/demo cad software. Um cnc control software with gcode, small videos with classes and demo’s of HOW-TO’s. Enough to cover cost and shipping and assist with the cost of domain and servers. Or free download, just not in an ISO form to make a CD. But rather all in raw form posted on the server in a presentable manner.
Also I move to make a statement, I believe it would be wise for us all to agree on one type or other for the DRIVE train. We basically have 3 options, standard threaded rod, ball bearing rod’s. or the other kind with the DEEP channel which I cant remember what its called. Belt drive has a tendency to shudder on the small scale. Wire drive stretches because it has to be pulled so tight. And geared track makes for a lot of noise (jitter) and low resolution. So it boils down to price when you really think about it. The standard threaded rod works great but its subject to wear, requires more Turk to turn and a lot of thin oil lube. But cost’s a little over a dollar for 3 feet. There turns per inch vary but, I’ve found them to be between 16-32 turns per inch. Average is 20-24 turns per inch, on the steal rods but they’re always an even number of turns per inch ALWAYS.
Ball bearing rods are not cheap and often don’t offer as many turns per inch. The outstanding factor though is the loss of friction and higher degree of accuracy per step and foot pounds to friction is almost non existent. A standard threaded rod has about +/- 1-2/64’s, as well as it increases over time and wear.
http://cnczone.com/forums/attachment...=&postid=31296 In this image the top axis is my Y-axis, the entire top Y-axis for every thing including motor (motor was salvaged) was under $10. My design as is gives about 6oz of force at 12v, but 20oz of force at 30v with out loosing any steps. The x and y axis are driven by the same piece of threaded rod cut in half.
I’ve given it much though, but the easiest way to entice people to try the cnc construction, would be the ultimate in simple design uni-polar driver circuit. 4 npn’s 4 resisters, a few traces or better yet an overhead view of a solder to protoboard with wires. A how to on testing it with two 1.5v batteries in series (3v minus the 4resisters) and a PC at/psu or any powers supply 12v. 5v would be better to use for safty but, not all motors will turn at that ratting. After the testing phase is proven working. A simple setup to the parallel port (5 wires 4 for step 1 to ground) and single dos program to make the motor live, and add start stop speed up and down (a counting feature comes to mind as well to help find what the motor can do). LED’s would be good to add for debugging but that’s what the battery is for.
Did I mention I can type 133words a min.
Originally Posted by jon 
