My tool for getting the heatbed leveled.
Best result is about 0,2 mm deviation between all four corners.
I use compression springs between heatbed and adjusting knobs.
Nice.
I have located the dial gauge permanently at the beam of the extruder. The measuring bar is hold up by a spring, so that height can be measured by pusing softly at the top of the bar. Is convenient to check if the initial height has been changed.
My experience is that the corners are not very representative. I am curious what your findings are when measuring in a grid (e.g. 4x4 with 50mm distance between measuring points) in the area within the bolts.
