While deciding to build the CNC Router I decided to build my own electronics. I should be capable and this should save money the oniy way I can afford this project is to keep the cost to an absolute minium.
Early research suggested Unipolar was simpler as it was mostly discrete components. Seems easier than those multi-legged things especially the tiny ones with my eyes.
After a false start through insufficient research and purchasing too small stepper motors I was offered some 116 oz/in (may be from a HP Printer) Steppers. On decyphering the specs I find that the torque is
116 in Parallel Bi-polar
116 in Series Bi-polar
82 in Unipolar
There goes the Unipolar. Ok but 2.5 A is on the high side for many designs
so lets go series only half the current. But you don't get any thing for nuthing.
higher speed torque drops of quicker with a series connection. Jee I've disseminated a lot of information in six weeks since I started building this THING ( I doo luve it really ).
Ok, we have decided Parallel Bi-polar and Phil (pmino), see the first post, has many great designs. So here we go with the Allegro A3977SED single sided board. I was going to use the Opto Isolated Breakout Board but cannot find a supplier for the Opto-couplers in Oz (too hard to get them from overseas) Phil, Mouser only lists an equivalent.(Thanks). I will use the standard 4 axis BOB and use only three.
Next post I will describe again my method of toner transfer as I would like it to appear in this Build-Log.
The Sawdust Creator.