Posting in hardware as that's where I would look for bed leveling help - even though this is a software-enabled tool. I use a PB+ and on occasion I've found that something or other will go wrong and my bed will end up needing to be leveled again. When I say leveled, though, I really mean that the clearance between the nozzle and the bed does not change as the nozzle moves around w/r/t the bed (whereas "level" would imply perpendicular to gravity, and tells nothing about clearance).
To that end, I've created a macro for pronterface to print a thin triangle picking up the two front corners and the rear-middle of the printing area. As I use a 3-point leveling system, this gives me a good way to judge whether clearance is correct all the way around. If the resulting bead of plastic is not stuck to the bed somewhere, I probably need to reduce clearance at the nearest corner. If things go well, I'll end up with a well-adhered triangle of uniform thickness (judging by eyeballing the width of the extruded material).
The gcode is simple:
G28 ; home all
G1 F1266 ; set feedrate
G92 E0 ; reset extruder coordinate to 0
G1 X0 Y0 Z0.4 E0 ; move to bottom-left, set Z coordinate - need to pick the right Z for your layer thickness, etc
G1 X5, Y0, E0 ; move to first corner
G1 X95, Y185, E4 ; move to second corner, extruding along the way
G1 X185, Y0, E8 ; move to third corner, extruding
G1 X5, Y0, E12 ; move back to first corner, extruding
G1 Z3 ; lift the nozzle when done
G1 X0, Y0 ; return home (nozzle lifted) for evaluation
I just run the above, look at the results, clean up if needed, adjust clearance if needed, and re-run.
Last edited by ivymike1031
on 2013-Aug-Mon-17-Aug, edited 1 time in total.