DIY Laser levelling using webcam and laser level

[devmonkey]

Thank Joe. I understand now. I think my confusion came from your first reply to me where you said "... so you can either zero both rails to this plane..."


Have you seen this project. Looks like it shares some similarities but for a very different result.

https://hackaday.io/project/21933-op...solution-laser

Dave.

I hadn't seen that particular project, but yes they are using a prism to project a line, However note the accuracy of the prism, it is ~1 arcminute (290um over 1m), this is fairly standard and although readily available unfortunately useless for our purposes, we need <1 arcsecond which are a rather more expensive and difficult to get.

[devmonkey]

I've been thinking about actually using this system to level the X beams (80mm steel box section) on my new machine, I will outline my current thoughts on the process and welcome your criticism.

I'm thinking the basic process would be:
1. Deposit a 30-40mm wide strip of machinable rail bed material on top of the beams where the rails will go.
2. Use the laser system to level a piece of milled aluminium plate with a window cut in it over where the rail will go. The plate could be clamped and brought into plane with the laser using 3 jack screws bearing on the steel beam.
3. Take a trim router and using the plate as a router guide mill the rail bed down to height. Move the plate along the beam, rinse and repeat, then repeat for the second X beam.

The trim router would be height locked throughout the whole procedure, potentially tape could be used on top of the router guide for a roughing cut, then removed for a finish cut. The laser would also have to remain in location.

For the rail bed I'm thinking of polyurethane metal filler laid to a depth of 1-2mm, hardens quickly and is fairly easy to machine.

I don't have a trim router, although I don't mind picking one up. Does anyone know what sort of Z-play units like the small Bosch or Makita have?

Thoughts on success of this process?