What's a dust lens? I have 2 Challenger 2's and I only notice the focus lens (G7). I have the 1 Watt 520 nm so I'm concerned.
Sanwu uses dust lenses on the top of their units, all but the Pockets. When your looking down from the top your looking at the dust lens. When you unscrew the top portion of the laser and look at the bottom you see the bottom of whatever lens your using.
I have had this problem on only one of my lasers and it is the one I carry with me everywhere, don't leave home without it.
It also is my special request build, where I had Sanwu push a Red Guardian up to 2.5-2.7 watts. Seeing how it collects a lot of dust and lint from my pocket. Even though I do the best I can to keep the dust lens clean, I use it a bunch, and in the course of time scratches and minuet dust collects and causes the dust cover to become pitted, which in turn causes the lens to get burned, which causes the beam to get distorted. The first and most severe dust lens that got burned happened when I accidentally turned it on when it was in my pocket. Was on for probably better than 3 minutes, which is a insanely long time. (hat tip to Sanwu for building such a unit that could take such abuse and still work like a top once she cooled off, she got smoking hot!) Which burned the first dust lens pretty bad, which brought the dust lens to my attention. So I kept a eye on them. The second is after a couple months worth of use. But you have you remember, I keep this one in my pocket so it's susceptible to getting burned much more than one not carried in one's pocket all the time.
I don't think you have much to worry about, just keep a eye on them and you'll be fine. Their only 3 dollars a piece and very easily replaced. Hope this sets your mind at ease so you can enjoy your lasers.
@ Arctic, sorry to derail your thread, please forgive. :can:
