Hooking the design to a specific location on the crumb tray is always a challenge. Even knowing the distance on the “x” angle is hard without a reference. You still need Set Focus to know the location at the top of the material but knowing it with reasonable accuracy when placing it in the crumb tray is a needed thing.
So …
The Set Focus is on the white bit of paper. the tape measure is…
Oh nice! Picked up a spool of 12" measuring tape masking tape, so when it gets banged up I can peel it off and replace - I bet the steel lasts a lot longer and it’s only a couple bucks more expensive!
The Tape is narrow and self-stick, but even with a cleaned camera lens a bit blurred but the key is a consistent point of measuring place to relate to what I put in.
Another piece I put on the right rail starting at 20". The metal is thin so as not to interfere with the pass-through but the top of the tape matches the extreme 11" in the Y direction so easy to locate and get horizontal while keeping it from being hit by the laser.
For the second tape I have not done anything yet but if on the left rail and should not interfere with the rest of the works as it is very thin.
I had two of these self-stick tape measures lying around years ago and installed one vertical and the other on a T-square I made on the 
and calibrated them both to the actual 0,0. Been loving it. I’m glad to see someone come up with a similar solution.
Ooh, this is a good idea, thanks.
