Monday, March 10, 2008

Laser-based referencing...

I received the laser modules I ordered from DealExtreme last week... Of the lot, I ordered a few that output cross-beam... These were meant to be used on my Sherline as a referencing tools (sorry 9W2GU, another cnc enhancement).

Here's how it was modified... Take the module apart but don't remove the laser from the center piece... Enlarge the original hole at the back (where the wires were) to fit suitable shaft... I used 6mm countersunk screw so I enlarge the hole to match... fix the shaft to the back case... then drill new hole on the side (diameter 3mm or larger) for new exit point for the wires... carefully reassemble... chuck it in your spindle, lower it to your preferred height and focus the lens for a finest line...

For alignment, drill a small hole on any workpiece... then without changing x-y, chuck the laser module in... adjust/tilt the focusing lense so that the lines cross exactly on the drilled hole... Loctite the lense, let it set and you're done...

The modified module...

The result on the Sherline... I was able to focus the lines to about 0.25mm in width... pretty good for a USD4 module and 15 minutes hack...

2 comments:

Anonymous said...

Is this a zero/edge finder that is mounted in the spindle? or is is mounted next to the spindle? Is mounted next to the spindle, wouldn't there be variance depending on height of head?
Cool hack, and I just bought the laser, but would like to know more about the design you made.

thanks for posting.

Basir Atan said...

It is not off the shelf edge finder... Just a normal laser module hacked to serve a purpose... :-)

It is mounted in the spindle directly... Slight variation in the spindle height does not change the beam width...