what is the difference with the original one and this one

I love how simple this was to assemble, but I have a couple of comments that might make sense for the next revision. Can you countersink the aluminum plate an include M3x16 flat head screws, plus washers and split washers? That's how I ended up modding my HBP. Also, I think a nice change to the PCB would involve changing the 3 pin connector to 0.1" spacing. This way, we can take a 3 pin SIP header and solder it to the board (as well as the power connection, which I think is already 0.1"). Now if a wire ever fails, instead of disassembling everything, you just have to unplug the wire and recrimp new ones. I guess some people hate crimp connectors, but if you have the tools, it's way easier. :)

I really like the 'Just hook it up to 12v' method. Couldn't be any easier!

I taped on double stick carpet tape purchased from Walmart. The tape has a cloth fiber backing. The tape's adhesive melts on the heated build platform and forms a flat sticky surface that the ABS adheres to. There is no problem pulling off any object because the surface is still wet and sticky. The heat keeps it from drying up. After multiple uses the adhesive eventually gets overcooked and dry up. So I just replace it.

Is it possible to build this as is, but without the LEDs (or maybe just one to show that it is on)? Would it still work?

I had to wire mine up with a relay, as the MOSFET on the extruder controller would almost immediately overheat when this was plugged in. Tried to heat sink it, but that still wasn't enough. Relay driven it's been fine now.

I like the idea, but i have some concerns about the LEDs sitting directly on the heater PCB. They are supposed to stay cooler than 85
°C according to the datasheet, but i fear that they could get quite a bit more heat if you go over 100°C on the platform, and fail in the long run... I did not check yet, but maybe there are some LEDs out there that would run at up to 125°C (automotive or industry approved parts usually support h
igher temp).
Someone already posted a pic in the forum with one of the LEDs burning a black mark into the wood platform, so i guess this cranks up the risk of fire and should be investigated!

In the words of the great philosopher Paris Hilton, "That's hot." ;)

dang, this thing is sexy. good work boys! i can't wait to get mine.

Am I correct in assuming that V1 was the Makerbot Hotness with the nicrome and glass setup?

If you are looking for RepRap Heated Bed solution (and others), see here:

http://reprap.org/wiki/Heated_Bedhttp://reprap.org/wiki/Heated_... :)

Does it actually glow like that? It's like the Knight Rider of makerbots.

SWEET!!! Awesome work Makerbot peoples!