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View Full Version : How do you focus your laser



Bruce Dorworth
04-20-2012, 5:04 PM
When I first received my laser, I was raising and lowering my table to focus the laser. Then someone mentioned that you loosen the nut on the focus tube and focus it that way, so I have been doing it that way. It is much easier and more accurate, but lately the threads on the nut seem to be a little gritty.

Is one way better than another?

Bruce

Richard Rumancik
04-20-2012, 5:27 PM
Bruce, as far as I know most of the laser systems don't have a movable focus tube like yours has. The GCC, ULS, Epilog, Trotec etc all use the moving-table method as far as I know.

I don't know your mechanics to say for sure if one method is better than another. I assume that your top mirror has to be fixed and you are changing the distance between the top mirror and focus lens when you adjust the "focus tube". Does it "telescope" up and down? If the focus tube is a precise assembly with no play then I suppose this should work fine. If there is play, then it could affect alignment. Most of us don't have any option as to how to focus . . . moving the table seems to work well.

Rich Harman
04-20-2012, 8:47 PM
Shenhui uses a moveable focus tube but the design permits the tube to wobble easily. It is simply a tube sliding within another tube and a set screw making contact at one point. I do not like the design, I use it with the tube in it's highest position to minimize movement - especially during rastering where there are high accelerations.

Another brand also has a sliding tube but it uses a clamp that secures the tube in place very well with no chance of wobbling.

Rodne Gold
04-20-2012, 10:53 PM
Better to use the table , moving the lens tends to throw the beam alignment you did with it in one position a bit off.