My K40 has worked fine for a year or two but now , it still cuts but I need to give it more power to work as well as it did before. More importantly the beam has got much wider.
My first thought was . align the mirrors and bed height again and thats when I found something odd
To line up the mirrors I always put a bit of paper over the hole in the laser head. Did a test fire and adjusted the mirrors till the small burnt spot was in the centre
but now I see I am not getting a small burnt spot , instead I am getting a ring like a letter " O " on the paper . The ring is about 2mm diameter and its only the edge thats burnt , the center is untouched .
What could cause this and is there a cure
I will try to add a pic to show the beam as it enters the laser head
the ruler is in mm for scale
Sorry it should have been TEM01 not TM01. The power density across the diameter of a laser output beam is not uniform and is dependent on the laser active medium, its internal dimensions, optical feedback design and the excitation system employed. The transverse cross sectional profile of a laser beam, which shows its power distribution, is called the transverse electromagnetic mode (TEM). The higher number TEM modes have a greater spread in intensity which makes it harder to focus into a fine spot.
@Abe_Fouhy no . It can’t be the lens . The picture of the burn is taken before the beam reaches the head or lens. Basically it’s the shape that the beam must be in as it leaves the laser tube
Cheers James. I accepted the others view that it’s goodnight Vienna for my tube. This afternoon I ordered a new 60w tube.
I have already got the rails and carriages to make a 1000mm x 500mm machine so with a 60w tube it should be a usefully bit of kit
