I finally finished my frame, now I tried calibrating the Maslow. The resulting tests are not accurate at all. I did the tests with a pencil on paper taped to frame, which works surprisingly well.
The top horizontal line (see picture) looks like a sad smiley (bowing downwards on the sides) , not straight at all. What might I be doing wrong and how can I improve it?
The calibration step where the chains are automatically extended to hang the slide seems to fail, the chains are not extended enough to hang the slide. I then manually extend both chains further out.