beam expander

[arthurvenet]

hy guys its been a while since my last post, dose anyone out there know how to install a
beam expander i am not shaw if it goes after the laser tube or after the first mirrow any
info would be apreciated arthur.

[twehr]

hy guys its been a while since my last post, dose anyone out there know how to install a
beam expander i am not shaw if it goes after the laser tube or after the first mirrow any
info would be apreciated arthur.

Put it between the tube and the first mirror.

[ltran2000]

What is beamexpander for ?

[twehr]

What is beamexpander for ?

It widens (expands) the beam coming out of the tube. Then when it hits the final lens, it all gets concentrated to a single point of focus. The wider the beam coming into the final lens, the more power it has once concentrated. Therefore, widening it before it gets to the lens gives you more final cutting/engraving power.

[Ya-Nvr-No]

I do not see any reason you cant put it after the first mirror, It just needs to be adjusted properly. So if you dont have the space available between the lens and first mirror like I find, then improvise. All they do is control the beam, straight and wider. Just make sure your within the diameter of your mirrors and focusing lens mirror. So going bigger is not in this case better. 2.5x is more than enough.

[baccus61]

Some manufacturers put the beam expander just before the final mirror on the X axis and have an elaborate system of moving it to adjust or focus for any deviation in the beam diameter. This is used typically on large gantry machines where beam divergence is a problem over the large distances involved, like on a cloth material cutting table for example.
If you have a relatively small machine say 1meter by 1meter then you wouldn't really need one. It's just added expense.
My machine is 1.4 x 900 and it works fine but I'm no professional either and if there is any irregularity then I don't notice it.
Rich.