Shape of Beam

[DonL]

My system seems to work OK, It engraves even at low power, I can engrave an image on paper that is very detailed and just light brown or tan color, or I can cut 1/4 inch MDF no problem, But when I look close at the beam mark left when I fire just a dot I get a nice circle and a half moon shadow like this

baddot.jpg (16.66 KiB) Viewed 2070 times

What causes this? My engravings would be much cleaner without this. Any ideas?

[Tech_Marco]

Check the 'window' lens of the laser tube. It could be something stuck there or the lens damage.
Also, take the focus lens out and double check whether the coating peer off or not
Last, touch the laser head feel how hot it is. A little warm is normal but if it is hot, then the beam must be hitting the side of the barrel


Marco

[DonL]

Check the 'window' lens of the laser tube. It could be something stuck there or the lens damage.
Also, take the focus lens out and double check whether the coating peer off or not
Last, touch the laser head feel how hot it is. A little warm is normal but if it is hot, then the beam must be hitting the side of the barrel


Marco

I checked the focus lense and it appeared OK, it is new from Lightobject so is of good quality, the circle with no lense is perfect, so I cleaned the lense and put it back and it seems OK now, may have been smoke on it from the last cut.
Thanks...

Don

[swamidog]

the mirror in your cutting head is out of alignment and the beam is bouncing off the edge of the aperture at the bottom of the nozzle.

My system seems to work OK, It engraves even at low power, I can engrave an image on paper that is very detailed and just light brown or tan color, or I can cut 1/4 inch MDF no problem, But when I look close at the beam mark left when I fire just a dot I get a nice circle and a half moon shadow like this

baddot.jpg

What causes this? My engravings would be much cleaner without this. Any ideas?

[DonL]

the mirror in your cutting head is out of alignment and the beam is bouncing off the edge of the aperture at the bottom of the nozzle.

My system seems to work OK, It engraves even at low power, I can engrave an image on paper that is very detailed and just light brown or tan color, or I can cut 1/4 inch MDF no problem, But when I look close at the beam mark left when I fire just a dot I get a nice circle and a half moon shadow like this

baddot.jpg

What causes this? My engravings would be much cleaner without this. Any ideas?

The focus head I have does not have a nozzle and the beam is hitting dead center of the lens so it is not a reflection from alignment in this case, although you are right, that could cause the same effect, In this case a dirty lens was the issue it seems as the problem is gone after I cleaned all mirrors and lenses.