Stepper Driver Hardware

I did quite a bit of research looking for a stepper driver board and motors suitable for my setup. I considered a TB6560 driver. There are a lot of them available on eBay. I was concerned about documentation, tech support and all. Not knowing a lot about the power requirements, and how to hook it all together, I decided on the Hobby CNC EZ Driver package that includes the driver board, stepper motors, and various other components for powering it. It did not come with a case or a transformer.

The entire package requires assembly. I don't have a lot of experience soldering PCBs. Most of my prior soldering is done with a small butane torch. Not exactly controlled heat. But with a little warm up practice I got the hang of things and I think I did a pretty good job. We'll see. I've put everything on the board except the driver chips. I have to test for 5V at a couple of key points. In order to do this I need to apply at least 12V DC to the board. I don't have a suitable power supply for this so I need to proceed with the rest of the assembly. Here's the almost-assembled driver board:

A friend of mine gave me a 24V 12A transformer. It's industrial strength. It's mounted in a NEMA 1 case, whatever that means. Anyway, it's big. It won't fit in the case the rest of the system was designed to go in, so I guess I'll have to mount it externally and make a power cord. Here's the transformer with 9V battery for scale (I didn't have a quarter on me). I was hoping to keep things as small as possible but I'd rather have such a robust power supply (that I got for free).

I managed to wire the transformer up and test it. 120V AC in and 23.7 V AC out, so that's good. I hooked it up to the bridge rectifier hoping to get something like 30+ V DC out of it. (I don't recall why it gives more than 24V. I'll look into that later.) Anyway, I got a beep from my multimeter but rather erratic numbers for voltage. I think that's to be expected since the AC signal sweeps back and forth and produces a pulsing DC signal. I've got a capacitor the size of a hamster that supposedly will smooth the signal out. This capacitor carries a "SEVERE SHOCK WARNING" in the instructions. Hopefully I won't kill myself.

I just got the case yesterday, so I'm ready to start the assembly of the major components. Here's the case. It's not bad looking at all. I'll be wasting a fair amount of space since there will be no transformer in it, but I will be putting the Arduino in it and down the road it will give me more flexibility. The front and rear cover are rectangular (no rounded edges or angles) so if I need to replace them as the configuration changes it should be easy enough.