Still calibrating, now also supporting

After last time's big failure, I'm not leaving complex prints alone until I am more satisfied with the sticking. I tried it again today, and with a height measurement of 0.4, I set a Z offset of 0.7, which resulted in warping after a few layers. With 0.5, the first layer was entirely white (which at least shows the bed is level to the X axis). It didn't strip nor warp, but the print has a very long flat slope that a) doesn't print nicely, and b) comes loose once the piece is big enough. For my next try, I will adjust the support settings to support any 35 degree angle, since using the default settings for this long overhang doesn't work:

Upside-down view of overhang not sufficiently supported

Starting procedure:

Home all
Center X/Y
G0 Z1
Put piece of paper under nozzle
Motors off
Move down Z by 0.1 at a time, checking if the paper can still be moved. It will be held slightly at some point, with 0.1 more it will be held fairly firmly.
Set Z offset to 1-#moves.
Home all
Spray bed with hairspray (still need to figure out if cold or hot bed is better when spraying, whether to dry off the spray, and whether to do multiple layers)
Start printing!

After talking with +Richard Jørgensen about his setup, I'm quite tempted to add a Raspberry Pi to control mine. Having to tether my main laptop for printing is not very handy (the SD card reader appears to be broken). Fortunately, nophead has already shown how.