Aftermarket Lenses and Windows

American Photonics now offers aftermarket lenses and, soon, windows for the Glowforge! This should be a great help since the Glowforge Store goes out of stock on replacement optics so often. I bought one to test and it works as well, if not better, than my two Glowforge original lenses.


Interesting. The lens itself is significantly smaller. Good luck!

The lens is the same size, the lip of the metal holder around it is just slightly larger. This is not a problem as the laser beam is significantly smaller than either holder’s opening.

I think “better” might be a stretch, but this is definitely a good option to consider in a pinch!

Thanks for the info, and by the way we miss you here in the forum. Your voice of reason on Facebook is often the only one.


Wouldn’t worry too much about the smaller lens aperture. If you have ever seen a picture of a burn spot on the laser head side window it’s clear that the laser beam diameter, even at that point, is quite a bit smaller than the window. At least as long as the tube alignment has been performed at the factory.


That still impresses me how well they hold alignment. I can only recall 2 or 3 problem and support cases over the history of this forum where I suspected the alignment was shot.

What surprises me is that we don’t see alignment changes when removing the head, checking the mirror which is only held in place by foam, and replacing the head only to be held in place by magnets.


The print head mirror sits on a lip that puts it at the right angle. As long as the mirror falls all the way down into the hole for it, it’s aligned. The bit of foam and the lid putting pressure on it almost guarantee it falls into place.

The problem are the mirrors you can’t touch. Every once in a while there’s an FB post about cuts not working on the right side of the bed on a brand new machine, and a picture like this when I ask if there’s discoloration on or around the print head window.

If things aren’t aligned on the way to the print head, there’s nothing we can do to fix that.

We have a pretty good idea how big the beam is:

From the no lens tests I did it’s bit larger than 0.08” diameter. It’s really not too wide, the lens is designed with lots of wiggle room.

Also the head mirror is very close to the end of things. If it’s off a bit you’ll be fine. The further back you go in the path the more misalignment will affect you, the error has more distance to deviate.