Changed the lens out from 2" to 3" to cut some 3/16" hardboard for jig. Never have much luck with cutting it - it's always burnt a lot more than I like, but going to make a jig to engrave some cork coasters to take to the show Saturday we are going to. Cone was on with 2" lens, but for some reason I didn't see it and put the sweep on like I always do when cutting with the 3" lens. Cone too short to direct air good, and as I found out tonight the beam hits the inside of the cone with the 3" lens. Ran the file and didn't cut out completely, so I ran it again. Still not cut thru, so I slowed speed down for 3rd time 100% power 60 & 75 watt cartridges together. Still not cut so I'm thinking time to get something else for jig. As I removed the 3" lens I noticed it felt warm. Never has before. Kind of wondering why, then I removed the air sweep and bumped the cone as I was doing so. Bottom of cone is discolored - almost a dull silver color. I always thought it was made of plastic with a very small magnet in it that tells the driver it is installed. I believe it is anodized aluminum now. Anyway, cone seized in holder. I thought best to try to remove holder and cone from carriage and work on it rather than while on laser. Got it off and removed circuit board on back of carriage and the holder appears to be plastic and also seized. Afraid to use a lot of force, dipped cone in water with ice in it while holding carriage housing to keep from getting circuit board still in it wet. Cannot remove it, seems like screws holding it are under housing holding cone. Figured this would be a good time to submit a help request to ULS and tell them what a dumb thing I did. Then come here to share with everyone. I am anal about attention to details. It often is the difference in fixing something and not, between a good job and a so so or poor job. I guess I will mentally be smacking myself in the head all night tonight. So - pay attention to what you are doing.