Tube on Gantry or Stationary

[prcdslnc13]

Building a 60w machine with a 2x4' machineable area. I was planning on mounting the tube on the gantry for the shortest possible beam distance, but is this needed? Its just added complexity, that Im sure I am capable of handling. But Im just curious if its needed complexity.

Im using this 60w tube http://www.lightobject.com/SP-60W-CO2-S ... e-P70.aspx

[AndyKunz]

I just did a complete step-by-step build thread for a 60W laser including the bill of materials. You don't want the tube to move.

http://www.rcgroups.com/forums/showthread.php?t=2243133

Andy

[prcdslnc13]

Andy,
I just burned through your thread in abour 10 minutes so excuse me if I missed it, but I saw you used a beam combiner, but did you need a beam expander at all? Any power loss at your lower right corner (longest beam travel)? If not Im going that route. Greatly simplifies the build.

[AndyKunz]

Andy,
I just burned through your thread in abour 10 minutes so excuse me if I missed it, but I saw you used a beam combiner, but did you need a beam expander at all? Any power loss at your lower right corner (longest beam travel)? If not Im going that route. Greatly simplifies the build.

I used both combiner and expander. They're both in the blue thing. Look at the photos in this post. http://www.rcgroups.com/forums/showpost ... tcount=182

The combiner is a lens at an angle. It takes the horizontal beam from the laser and a vertical beam from the red dot and sends them out horizontally into the beam expander, which is a series of lenses in the black metal tube that's sticking out the side.

No loss of power at all - it burns fine over the whole table area.

Andy

[prcdslnc13]

Well awesome. You just made this project a whole lot easier.

[AndyKunz]

My goal was to make it as step-by-step simple to follow along as I possibly could. Since there isn't an "assembly manual" it was a way of helping folks get the info they needed.

Andy

[prcdslnc13]

I did a k40 conversion and Ive built about 7 3D printers and a few cnc mills and routers so Im pretty comfortable with a large part of this. But the laser specific stuff I am still a bit short. specifically things like power density, So I appreciate it.

[AndyKunz]

The beauty of laser light is that it stays together, so you don't have great power losses over reasonable distances. Keep the smoke away and there's no reason to worry about it in a machine.

Andy

[prcdslnc13]

Andy
When you setup your expander how did you align your beam to it? I am having issues with the expander moving my beam. Did you align everything with out the expander in the mount and try to shoot the center of the mount hole?

Also do the threads of the expander hit the combiners mirror mount? mine protrudes out about an 1/8th" and pushes the mirror back.