Photos below show a variety of marks on my tape
Forgot to say earlier: that's a nice little setup you have there ![ThumbsUp :-+](https://www.eevblog.com/forum/Smileys/default/icon_smile_thumbsup.gif.pagespeed.ce._JElyJQqdB.gif)
Thankyou
![Smiley :)](https://www.eevblog.com/forum/Smileys/default/xsmiley.gif.pagespeed.ic.R8GFI-pF6f.png)
Screwing the shaped board to my bookshelf to fit it has been perfect. It's now "ready to print" any time, rather than requiring me moving it, wiring it and re-levelling it every time some small printing takes my fancy.
This printer design has a fatal flaw in that the left and right steppers for the Z axis go out of sync if you apply outside force to the gantry (eg when changing filament). Until I worked this out I was constantly recalibrating bed levelling to suit the crooked gantry. Now instead I use two high-precision calibrated german manufactured length standards (read: two flat AAA batteries) to fix this problem:
1. Home
2. G0 Z40 (raise the gantry 40mm)
3. Place the two AAA's against each vertical threaded rod
4. G0 Z0 (lower the gantry until it crashes into the AAA's and skips several steps)
5. G0 Z10 (relieve pressure off the AAA's)
6. Remove AAA's
7. Home again.
Voila, everything is straight and reliable now. I do not have to re-level the bed anymore (unless my dodgy Z-top wiggles, but then I wiggle it back). I literally do a few prints, leave it for a few weeks, come back and print some more without having to worry about levelling (or buying auto-levelling devices).
When I printed directly onto the glass I had to change the Z-stop (or re-level) when changing between PLA temps and PETG temps. I have not had to do this at all for a long time, I think a combination of a fatter first layer (0.35mm, even when doing the rest as finer layers) and the soft masking tape has helped me here. Again, avoiding the fiddly stuff means I can just print whenever I want now
![Smiley :)](https://www.eevblog.com/forum/Smileys/default/xsmiley.gif.pagespeed.ic.R8GFI-pF6f.png)
EDIT: Said length standards can be seen stuck to a magnet on the top-left of my printer in the earlier photo.