Third Mirror Getting Hot ! Any İdea ?

[Atacan Gucuksahin]

Hi there ,

I have been struggling with this for the last week . I have tried everything that came to my mind to solve this issue but nothing helped so far. I'm going to make a list from the things that i have tried just to make it easier for you to have an opinion on this situation. My tubes are both Efr 130-150 Watt and i have this problem with both of my laser heads . Any help is appreciated . Thanks a lot .

- I re-aligned all the mirrors multiple times so my mirrors are almost perfectly alligned .
- I replaced the mirrors with new ones which didn't make any difference.
- Tubes are almost 2,5 years old but still cutting really good just as the last year and before . Moreover, both third mirrors on the different heads started getting hot at the same time . So, if ıts because of the tubes, is it possible to have the same problem at the exact same time with both of them ?
- It doesn't take too long for the third Mirror to get hot . If i run two consecutive 7 minute programs , then it Gets very hot and my vertical alignment is very much affected by this hotness.
- I also checked if ıts getting hot where Lenses are placed on the laser head but the area where Lenses are placed is cool so the only part getting hot is the third Mirror.
- All the mirrors are Mo mirrors sold by Cloudray brand.

Those are my efforts and findings on my problem . Hopefully you will enlighten me with your thoughts and i also hope that this subject is going help others who suffer from relative problems. I have searched the forum but couldnt find anything that is familiar with this circumstance .

Thanks in advance.

Ata.

[Dave Vigness]

I'm assuming you verified it's the mirrors and not the head that is heating up.

Have you done a pulse at full power to see the actual size of the beam? Only reason I'm asking is possible beam spread in an older tube. Low power pulses would be small, but full power full size beam could be clipping if you have the factory head. With my factory head, the incoming hole was about 2.5mm off center, and I was right on the edge of beam clipping even with a new tube. Went from the factory head with a 20mm mirror to Russ' lightweight open head and a 25mm mirror and never looked back.

[Pete Cyr]

Either the mirror is dirty and or the beam is hitting some portion of the head as Dave indicated.

[Atacan Gucuksahin]

Thank you so much for both of your comments guys . I didn't think of hitting pulse with full power so i will do that .

Thanks again

Ata.

[Atacan Gucuksahin]

Hello again ,

I have just tested your idea Dave. What im seeing is actually indicates that some portion of the laser head is getting hit by the pulse as you have mentioned before. (Thank you so much) So i hit the pulse for a moment at half power to see that im near center . Than i switched to full power and hit the pulse for 5 seconds and the masking tape located at the left of the head started to burn . I will put two pictures to make sure that im interpreting correctly ?

If that's really the case, can i do something to work with these tubes without hitting the laser head or (I'm not optimistic because 5 second burn mark seemed way too large to work with) should i change the tubes with the New ones . Since New tubes are so expensive, i need to find another solution to this issue if that's possible. So , do you have any idea how to figure this out ?

Best Regards .

Ata

[Pete Cyr]

I suspect you need to adjust your mirrors
see link
https://www.youtube.com/watch?v=wY5D27TQwZI

[Atacan Gucuksahin]

Thanks Pete . But my mirrors are perfectly alligned(almost) so i don't think that's the reason why im getting that second burn mark adjacent to the left of my laser head. That second burn mark is happening when i pulse with full power .

Do you think of anything else sir ?

Thanks again

Ata

[Pete Cyr]

I cant think of anything that changes the beam position when increasing of decreasing power.

[Dave Vigness]

Only thing I can suggest to double check your alignment, is put the target on the head and move it as far from the #2 mirror to check your #1 to #2 alignment. I was hunting alignment phantoms for months until someone passed this on to me. The extra distance between the #2 and #3 acts like an amplifier for the #1 to #2 error. #1 to #2 may be pretty close, but when you add in the distance across to #3 it becomes problematic.

[Atacan Gucuksahin]

I have tested the pulse at all the four corners of the machine but the pulse is at exactly in the same position across the laser bed . This is true for both second and the third Mirror . So , how is it possible for mirrors to be misaligned in this situation ?

Dave , i believe what you have told me before is happening to me, so the beam size is actually way larger than it seems to me . In the two pictures i shared with you , i didn't change the position of the head, i just switched to full power and pulsed for a consecutive 5 seconds . So , beam position doesn't change but there is another part of the beam that cannot be seen when i pulse for a moment. But when i press pulse for a long time i see somewhere else is alo burning alongside the original pulse position