My cheap 40W chinese laser cutter (brand 'ecpur') included a red cross laser pointer for assisting positioning, but it was mounted fiddly and at an angle, so the focus point depends on the object height.
This design replaces the laser pointer with two line-type laser pointers at 90 degree angles. When positioned correctly, the intersection of the two beams matches the cutting point at every object height.
The lasers are enclosed in ball joints for adjustment. Designed for laser pointers of 12mm diameter, these can be bought on ebay from china cheaply.
laserlaser.jscad | 5.8KB | |
laserlaser_2__1_.stl | 366.8KB | |
laserlaser_3__1_.stl | 143.6KB |