A horrible suspicion

Continuing the dowel tests.

0.2mm layer height, outer walls first, .9 extr. mult.: 5.45 - 5.55 mm male/5.42-5.47 female

Changed TEMP_RESIDENCY_TIME in Marlin to 10 seconds. 60 seconds is just time during which the filament can drool and the hair spray dry.

Another print died yesterday due to being too close to the bed. I suspect that the MDF changes size a bit depending on weather - hard to measure directly , but enough to cause trouble. This clearly calls for auto-levelling.