Heated Bed Questions

[amerrigan]

Hi,
Please someone correct me if I'm wrong, but I think I've spotted a manufacturing problem at Geeetech on all their 3D printer....

I was under the impression that the PCB traces (i.e. the "lines") of the Mk2B heated bed should be against the glass and not facing down?

I've also noticed that the thermistor is mounted with kapton on the "lines" side rather than through the central hole (so it touches the glass). The current thermistor placement does mean an accurate reading however (as everything is upside down and) as fiberglass is an excellent insulator the heat doesn't travel so well to the glass side.

Surely the correct installation for the bed is:

1) wiring, resistor and LEDs soldered on smooth PCB side; not the trace/lines side
2) Thermistor mounted through central hole, thus touching glass; not taped to the bed surface.
3) PCB traces/lines touching glass, not facing down heating the void?

Tony