Good news: My replacement GF unit arrived yesterday! (A day early!)
Bad news: I was unpacking it and there seems to be a problem with the lens. (My previous GF didn’t have this problem.)
Specifically, when I opened the inside foam, I saw a small yellow lens sitting next to the laser head. Going through the manual, I saw that this belongs on the laser head. However, I don’t know how to attach it to the open hole on the side of the lens head.
Most lasers operate without such airtight mirrors. For that I don’t think it’s much of an issue, but the autofocus mechanism definitely needs to stay as clean as possible to prevent it locking up.
That window is a glowforge innovation to reduce the cleaning maintenance on the mirror and backside of the focus lens.
It greatly reduced the need, but doesn’t eliminate it entirely.
When the exhaust was restricted on this machine, it got filthy inside. I found I had to remove that window to clean the inside of it. There is a tiny fan in the head that blows air (from inside the machine) down the lens bore to keep smoke off the lens.
After extended use (or a situation where exhaust blockage caused unusually dirty air to be induced into the lens bore) the head will need a good internal cleaning.
With the window, lens and mirror removed from the head it can be cleaned with compressed air and the passages wiped out with a lens cleaner pushed around with a Q-tip. (be careful pushing around the lens seat which has a 1/2" movement to it, be gentle)
Bear in mind the lens, mirror and window are the expensive removable components inside of the head. Use great care in their handling.
The window shouldn’t have come out like that, it just wasn’t tightened properly. As others have said, no harm to the machine
Note this is not official, condoned or recommended as far as I know, but is what I had to do to clean the residue from the optics in the head.
