Definately a scrapyard challenge

[Jonathan]

How easy is a self built power supply???

zapp have this as a kit http://www.zappautomation.co.uk/prod...547704f50af02c £316

Do you think these are too cheap or worth a punt http://www.ebay.co.uk/itm/2508624928...ht_3191wt_1110

Very easy to make a power supply. Connect primary of transformer to mains via a fuse, secondary to bridge rectifier (e.g. bit excessive but you can't go wrong with http://www.rapidonline.com/Electroni...ctifiers-29671) and output of rectifier to smoothing capacitors. Minimum about 10,000uF, 80V or greater. Switch on and check the output voltage and polarity is correct with multimeter just to be sure then connect it to the stepper drivers.

I tested a driver that looked identical to the ones you've linked to on eBay. I'd happily buy them if I needed some 50V drivers.

Edit to add:
Apparently it's not blatantly obvious this 4 line post isn't a substitute for proper research, so please note that this isn't a set of complete instructions but a general guideline.