This indicator shows the approximate material usage of a typical Zortrax spool, no need to peek behind the machine any more.
It assumes that the spool diameter reduces from 180mm on a full spool to approx. 90mm on an empty spool. Because there is more material on the outer diameter initially, druing printing the spool diameter will drop slowly at first, but faster the emptier the spool becomes. This is the reason for the nonlinear scale as shon in the images.
This setup requires that you use original Zortrax spools and the original spool holder. Only that way the spool is guaranteed to be in the right place for easy installation.
– I printed the scale and bearing in Z-ULTRAT and the needle in Z-ABS, but I guess that any material is fine.
– I printed all parts with .19mm thickness.
– If the needle should not fit due to warping, I suggest warming it up with a hot air gun and reforming it slightly.
– Updated the full and empty diameters for the approximation to 170mm and 83mm respectively.