PCB heated print bed

PCB heated bed. I'm working on this idea for nearly two months, inspired by http://www.neufeld.newton.ks.us/electronics/?p=864 .

UPDATE
------
tested at 110W and its working flawlesly, gives 108°C in few mins
Now I'm working on great mounting solution

This is V4
--------

- 22x20cm hated area
- you can select what resistance you want 1.3ohms (110W at 12V) or 21ohms
- you dont need any steel or aluminium on top, just plane kapton tape

(I'm testing it at 21ohms setup with 55V PSU which gives me 144W and about 110-120°C, will test with 12V soon and I'll give a report)