-First off, this is by no ways an end all, be all! I did not take any photos during the making of, but it is very straight forward!
-Second: what I did does require you to do some wiring with 110 lines. Clearly, a warning of "do not touch live lines. Do not work with live lines. Ensure everything is disconnect before touch anything exposed" is needed.
-Third: I will help as much as I can, but I'm still learning myself, so my own knowledge is limited.
-And the final point: thanks to iceng and steveastrouk for helping with this!
Anyways, with that handled, heres the nuts of bolts of the thing. Gen6 does not have control for the heat bed. As such, if you wish to add a heat bed to your build platform of your 3D printer, you need some other means to do it. There is quite a number of ways to do this, but all of what I found were either pricey, or limited you to one set temp. Seeing as how my printer (Prusa l2) can handle ABS and PLA, this was not something I wanted to do.
So, what I did was get a simply PID-based temp controller, and hooked that up to my system!
Below is a BOM of what is needed:
-ATX power supply (you may have this for your 3D printer already: all you need is a 4 pin molex off of the ATX)
-Some form of project box* (I used this one from makerfarm)
-LED* (any will do)
-Resistor* (for the LED)
-Small SPDT switch*
-Scrap wire (some to handle 12v and maybe some to handle 110v)
-Replacement tool cord (only needed if you don't used the 110v wire)
-Terminal post screws and/or wire connectors*
-PID contronller (this is the one I bought)
*These are not needed, but do make things easier to keep together, easier to turn on/off, and easier to see when its on/off. This will use all items on the BOM, but you can scrap what is not needed for your usage.
With the parts bought, what you need to do next is give your PID controller some power. The one listed on the BOM has a need for 110. What I did was just get a chunk of wire going into the ATXs main input (sadly, before the switch) and wire it up to the PID controller. Quick plugin gave me a "beep" from the PID, showing it power, but no sensor. That would be step two.
The PID controller has two function to it: heating and cooling. Once you set the temp you want the bed to be, it will take a reading via the sensor, and see if it needs to cool or heat said bed. In this case, were doing only heating. So you will need to get some spare wire, and hook up both the sensor and heating point to the outside of the project box. Keep this in mind:
-The sensor has no polarity, and just need a straight run from the PID to the terminal posts on the outside of your box. Goes without saying, terminal posts are not needed, but I liked to have them for a disconnect if I need to move my printer
-The heating contact will need power! This is where the 4 pin molex come from. You just need to treat the heating contact of the PID as a switch (SPDT) that you could controller, putting power (no more then 110v and 10a) into it that will run to the heat bed. Again, I have terminal posts on the outside that hook up to the heat bed.
Once you have that done, your pretty much set! The sensor that comes with your PID will need to be mounted to the underside of your heatbed. As far as the other items in the BOM, these are used for the ATX power supply, which should be hooked up to the printer. If you don't have an ATX already hooked up, the basic jist of the hookup is as follows:
-12v/gnd: these two will hook up to power the Gen^ board (mind the polarity!!)
-Green wire from the 20 pin/GND: these two (when connected) will turn the ATX on. I have a switch on the box to turn the ATX on/off
-Gray wire from ATX/GND: these two hook up to the LED, to inicate if the ATX is on/off. Again, mind polarity, and give the LED the needed resistance!
And as a closing remark, I know this is a bit looseend, but I would assume anyone who has made a RepRap will know what they are doing, and be able to follow. If for whatever reason you have an issue, feel free to ask! I will help as best I can!