DIY Laser levelling using webcam and laser level

[devmonkey]

Kitwn, about using it for tramming I would attach my sensor block to a T-bar in the spindle as if I was tramming a mill with a single dial indicator. Rotate the spindle and take sensor height readings at 0, 120 and 240 degrees rotation. Take plane described by these 3 3D points, calculate the plane normal and determine the error to the plane normal of your x axis plane, then shim the z axis until the normals are the same.

I will have a think about squaring but this is usually easy to do with dual x axis machines after skimming the bed by drilling 4 corners of a large square and checking diagonals using a stick with an indicator on the end, adjust home proximity sensors, re-home, repeat.

If at any point after initially bringing the x rails into plane you need to re-establish this plane in order to do something like tramming, it is unlikely the laser can be put back where it was initially. However since the rails are still planar the laser can be setup again and 3 points measured 2 from one rail, one from the other and the x plane normal established relative to the new laser normal. This is similar to moving between machine and workpiece coordinate systems in a CAM programme. For tramming we would align the spindle normal to the x plane normal via the laser normal, i.e. When the two errors are the same the spindle is trammed.