Patrick here
Thanks for the words of defense. The 1.2 and 1.3 versions have been depreciated quite a while ago for some of the flaws that it exhibited. As I design new machines, I obviously design them to remove the bugs and provide enhancements. Also, the 1.3 is offered as .nc code for those who are adventurous. I encourage those who want to purchase the joescnc and also want to try their hand at the mechmate. They are both excellent systems and deserve quite a bit of credit, especially since these systems provided a lot of my motivation. I have a passion for designing and building these machines and I hope this shows through.
It is my nature to try radical designs such as the roller chain method of drive mechanics. This is how innovation happens. So far, it runs maintenance free. The roller chain doesn't lose tension since the load from the machine is very light (as compared to it's relative use on motorcycles and other chain driving machinery with extreme loads). With 425 oz-in stepping motors, I am able to get problem free 1500 ipm on the y axis and 1000 ipm on the x-axis rapids. Cutting at depths of the tool diameter is quite good at 100 ipm into MDF. I get some chatter routing into aluminum at that speed, but when lowered to 60 ipm at very shallow depths, it's very smooth. Even pcb routing is quite precise with the roller chain, which was a surprise to me.
Employment motivation: fun and happiness, not money!
Video build log: http://www.buildyourcnc.com