Would cheap DX 9 port hubs (+ 10th port on the end) + 20A 5V supply + DC Barrel plugs + 0.5mm^2 wire + some ability to know which is the hot end of the soldering iron meet the needs?
I've just got to get two more barrel jacks as some cable wire, and I could have 36 happily mining in my ghetto cooling duct. 18 are quite happily mining at the moment - I've added one hub of 9 more since I posted the photos.
I've spent US$80 on the hubs and PSU so far, which makes it <$3 per port. But hey, they could stop working without warning, I suppose.
I'm assuming you got this hub:
http://dx.com/p/10-port-usb-2-0-hub-with-external-power-source-100-240v-ac-adapter-33191And maybe this power supply:
http://dx.com/p/5v-20a-iron-case-power-supply-silver-ac-110-220v-124499Couldn't you do this with no soldering by just cutting off the power supply wires from the wall wart at the base, and connecting them to the screw terminals of the power supply? I guess it depends on whether the wires could handle the extra current.
I will be trying something similar, same USB 10 port hub (bought at local market 2 for $20) and a 5V 8A 40W power supply from China (may take couple weeks to arrive)
5V 8A 40W power supply
http://www.ebay.com.au/itm/AC-Converter-Adapter-DC-5V-8A-40W-Power-Supply-Charger-DC-5-5mm-US-EU-UK-AU-plug-/22122720234110 port USB HUB
http://www.ebay.com.au/itm/New-10-Ports-USB-2-0-HUB-High-Speed-with-Power-Charger-for-PC-Desktop-Notebook-/300932835846NOTE:
I don't know if you guys are already aware, but with the usb hub above (and probably others are similar), I had to cut the RED (+) wire in the usb cables. This was because I had 2 of these hubs plugged in the RPi with the stock 2A power supplies and one of the power supplies stopped working which made both usb hubs receive power from one power supply, or possibly the usb hub was drawing power from the RPi power supply also. If I didn't unplug everything quickly it could have damaged more. I also read somewhere in this forum that 'power-backing' occurs when using powered usb hubs, where the RPi receives power from the usb cable and from its own power supply.
this is my setup at moment - can safely run 3 on each hub with stock power supplies.
ps. the fan on the laptop cooler doesn't do a thing in the ways of cooling the erupters, but the blue LED looks good.
I will post back results with the 5V 8A power supply when I receive it from China.