I just got a ESS Smooth Stepper board and a CNC4PC breakout board to go with it. The stepper board is nicely made, with large mounting holes that the average home CNC builder should have no problem mounting it. However the CNC4PC breakout board is a serious disappointment! NO mounting holes at all! Connectors for wires all the way around and not a mounting hole anywhere! Do machines vibrate? Wiring diagrams? In their PDF manual page 3-2 was missing completely. No big deal, that's just the only page that deals with ALL the outputs!
I bought a little stepper pulser card to control a stepper driver for motor testing. No instructions. A couple of jumpers that aren't marked. Terminals marked +12, Grd, Puls, and Dir. Should be simple to hook up right? Motor runs smoothly in one direction, chatters like hell in the other. After screwing around for 1/2 an hour I discover that this card actually implements forward pulses and reverse pulses, NOT pulse and direction as marked!
I bought a heater control board of 3D printing. No instructions. Two boards stacked in an offset. One tiny set of mounting holes through both boards, and they don't line up! NO marking of the pins except for power plus and minus. Came with a booster card with input and output terminals, not even marked for + and -.
It is unbelievable what people are apparently willing to accept. I have a friend who just bought a million bucks worth of surface mount assembly machines, and he is the best microprocessor guy I know. He used to build a single board computer for me that went in machines that saw 120 degrees continuously and the failure rate on the hundreds of boards I bought was really low. In fact hundreds of them are still running 18 years later I'm going to have to ask him what it would cost build some quality stuff here in the US.
Gary H. Lucas