mount a red dot laser horizontally in a mount put into your spindle and spin at <1000 RPM.
Doesn’t matter if the laser isn’t perfectly horizontal as long as you measure at equal distance from the spindle.
Can you elaborate? Is the idea to hold a ruler vertically all around the perimeter and measure the light cast? Is the light directional such that you’d see a clean line, then adjust? I like the idea of a light-based tramming process but just don’t understand yet.
yes, it’s a red dot laser spinning at ~1000 rpm so it looks like a line and the line will be 90 deg to the spindle. Unless you make it so you are 100% accurate with the laser pointing 90 deg to the mount you just have to measure the same distance from the spindle around the work area to know if your ‘tramming’ is correct or off.
ie. if you measure 200mm in front of the spindle and get 25mm then measure 200mm behind the spindle and get 30mm then your spindle is tilted forward.