HELP LOSING POWER / 80watt C02

[sehio]

Dear members,

I am new at this forum. I am Sergio Torres and I'm from Spain.

I started in cnc world like 1 year ago with my first purchase: a 6090 router, 2,2kw liquid cooled and very very happy with it.



I decided to buy a 4060cnc laser 80w. It has good price and was enough for my purposes. I am trying to start making motorcycle pieces, accesories and those...



Machine is very pretty. I tested engraving and cutting and love it (I have never seen one before mine)

Problem is next:

I am able to cut 5mm acrylic with 50% and 5mm/s , but I am not able to cut it if I increase power up to 50% (60,70,80%)

I have done about thousand tests, and I can define for you here easily:


It's an engraving test: 10% - 75%. You can see how 50% is deeper than 75% at same speed.

So, I have read all internet posts and videos and found this great forum. Seems to have a lot of material, solved problems and many many professional at the CNC area.

Even so, seller of machine is investigating with her team WHY my machine can't give more than 50% of power, nor if it's giving 50% of 80w. Lot of Skype calls for days trying to solve the problem without unsuccesfully.

I have checked mirror lens, focus lens, cleaned and adjusted them. I have checked power supply, opened and adjusted the screw knob as they told me. Machine has a ground wire with a bar nailed like 20cms to the earth. I use distilled water and laser beam is good color, between pink and purple.

Laser tube has a bit of bubbles adhered to the tube walls, but laser tube engineer told me it won't affect, nor a bit of arc done by the beam at the end of the tube.

I am really worried about this. I haven't done any electrical test because I am not sure about doing it, but I feel capable of doing anything. I am good at machines & softwares, I learn very fast.

What could you think I should start testing? May be that the power supply doesn't give enough power? It can increase power from 0 to 50% and it starts decreasing power while I increase current value in control panel.

Forgive me if my English is not as well as yours, I have tried my best to explain my problem.

Thank you very much for your replies and thanks to this forum for give me an opportunity to tell my problem.

Best regards mates!

Similar Threads:

• Problem- Universal laser losing power
• xy losing 0 when i power off and on
• Problem- New K40 losing power in 3-5 seconds
• Losing Laser Power
• Need Help!- Keep Losing power too my system.

[sehio]

I have an update.

This is a video record about my laser tube behavior working.



Damaged tube?

Thank you!

[abyss]

First thing: at 0:18 of your video are visible bubbles of air in cooling chamber near back mirror. This is not good in working laser, avoid - as can cause overheating of the inner mirror. You should use beam power meter to check what power is emitted from your laser. And you mention something about "little arc". Do you mean arc OUTSIDE of the tube - or just this "rotating discharge" inside the tube? Don't worry about this inner rotation of discharge.

[jalessi]

Sehio,

Turn of the lights in the room or wait until it is dark and check to see if the laser tube is arcing as you raise and lower the power.

Welcome to the Zone,

Jeff...

[sehio]

First thing: at 0:18 of your video are visible bubbles of air in cooling chamber near back mirror. This is not good in working laser, avoid - as can cause overheating of the inner mirror. You should use beam power meter to check what power is emitted from your laser. And you mention something about "little arc". Do you mean arc OUTSIDE of the tube - or just this "rotating discharge" inside the tube? Don't worry about this inner rotation of discharge.

Dear Abyss,

just bought an anmeter for installing today.

How can I solve bubbles problems? Anyway my losing power issue has been done since first moment. I am using distilled water with a bit of car liquid coolant with water pump.

About the "arc", I mean an inner rotator arc.

Here is other youtube user video that recorded the same.


I have recorded a video has Jalessi told me.



"This is the behavior of 80w laser beam when power is raised from 5% to 85% in steps of 10%. Each time the laser beam stops, it increases 10% of power."

Sehio,

Turn of the lights in the room or wait until it is dark and check to see if the laser tube is arcing as you raise and lower the power.

Welcome to the Zone,

Jeff...

Since yesterday, I have done an exhaustive adjustment of mirror and lens focus. Now I am able to cut a bit faster (6mm/s) acrylic of 5mm with 55%. If I raise power I only get a deep engrave, but I could test how laser beam is brighter. Between 55% and 85% is different.

So MANY THANS for your replies guys. Very glad with them. I am sure I will get this working and your help will be essential. All I need is time and think about it (and love hehehe)

Thank you very much.
Hugs.

[abyss]

What brand / model is your tube? Sometime there are small stickers under seller one, examine them - you can use flashlight to read what is under. When you will know it you can check maximum mA you can use.
And at the previous test I was not talking about mA meter but about BEAM power meter device. This will give you definite answer about power you have. Ask somebody around Spain to help you with it.

[sehio]

What brand / model is your tube? Sometime there are small stickers under seller one, examine them - you can use flashlight to read what is under. When you will know it you can check maximum mA you can use.
And at the previous test I was not talking about mA meter but about BEAM power meter device. This will give you definite answer about power you have. Ask somebody around Spain to help you with it.

Thanks for your reply. Really don't know the brand. I know the seller and have a lot of cnc products. Anyway I have tried to find help here and found 2 engineers with laser experience. I have been this morning with them checking machine and could realise that machine's power is less than 80w laser machine would give. Now we will try other power supply. If it's not, I will ask for tube replacement.

Thank you all again for replies!!

Br!

[jalessi]

Sehio,

Some laser users have reported issues with certain types of antifreeze '"car liquid coolant" causing internal conductivity within the laser tube and loss of power.

Certain antifreeze types conduct electricity and cause a path for the high voltage to divert away from the laser tube.

Your climate is not prone to freezing temperatures correct?

Flushing the entire cooling system and using only pure distilled water may eliminate the problem you are experiencing.
It cost pennies to test the theory.

Jeff...

[sehio]

Sehio,

Some laser users have reported issues with certain types of antifreeze '"car liquid coolant" causing internal conductivity within the laser tube and loss of power.

Certain antifreeze types conduct electricity and cause a path for the high voltage to divert away from the laser tube.

Your climate is not prone to freezing temperatures correct?

Flushing the entire cooling system and using only pure distilled water may eliminate the problem you are experiencing.
It cost pennies to test the theory.

Jeff...

Dear Jeff,

I bought about 15L of distilled water to test this and couldn't find solution. I added a bit of car antifreeze because I had read ppl use it. May br wrong, I can take it out and start with new distilled water only charge, but I guess problem will still be happening

I found too, many users with same problem as mine, different machines like K40. They are using distilled water as you recommended and can't avoid this issue. Inner rotation laser on end of the tube is normal on laser tube?

Could anyone record a video of laser tube working and film end tube?

Thank you very much... I hope I could solve it and post solution for this anormal behavior.

[jalessi]

All Mercadona Supermarkets have distilled water and it is not very expensive.

https://www.mercadona.es/en/supermarkets

[sehio]

All Mercadona Supermarkets have distilled water and it is not very expensive.

https://www.mercadona.es/en/supermarkets

Hahahah, I love your reply mate!!! I bought there hehe.

I am going to change again liquid cooler for pure distilled water with no car cooler. Any recommendation for cleaning inner tube?

Thank you!!!!

[jalessi]

My only suggestion is to make sure the laser and water is at room temperature (ambient) and flush with new distilled water until water runs clear.

Hahahah, I love your reply mate!!! I bought there hehe.

I am going to change again liquid cooler for pure distilled water with no car cooler. Any recommendation for cleaning inner tube?

Thank you!!!!

[sehio]

My only suggestion is to make sure the laser and water is at room temperature (ambient) and flush with new distilled water until water runs clear.

I show you my setup

Now I haven't bubbles. They just dissappeared hehe :-)

[sehio]

Update:

Cleaned all cooling circuit with 10L of tap water and then cleaned with 5L of distilled water. Now have beq 5L of pure distilled water. No changes. I burnt myself doing test haha.

I have to say, I installed an anmeter and at 65% it gives 15mA (and PSU is 40kV DC output). I guess it's not giving 40kV or there's something wrong with laser tube.

REUPDATE:

I disassembled focus lens for second time and took some pictures to show you. First time I found some scratch rings on convexe upper face. Now, it is still there and found a degradation with circle form on concave underside. Is it enough for not giving power? I want to explain that this ring seems to be the mark of the ring nut that has laser head to tighten focus lens. Second degradated ring is a new one never seen before. (2 weeks testing)



thank you!

[vrc321]

The top picture of the circle scratch on the lens occurred how you surmised and will not be the source of your problem. Can't really see the second picture to tell if that is a reflection or damage that actually matters.

How often have you driven your tube over 70% while cutting? Often, driving over 70% will be putting too much power through the tube. This can quickly degrade the tube.

[sehio]

The top picture of the circle scratch on the lens occurred how you surmised and will not be the source of your problem. Can't really see the second picture to tell if that is a reflection or damage that actually matters.

How often have you driven your tube over 70% while cutting? Often, driving over 70% will be putting too much power through the tube. This can quickly degrade the tube.

Thanks for your reply VRC321

I cleaned lens. There is only an small circle scratch due to the tighten of the nut.

Machine is "new" and I am not working with it, only test. So... may have 1 hour of total use. Never passed 75% and almost all test about 55/65% of power.

Someone told me that problem may be the flyback. I ordered a new PSU and I am waiting for it. I hope that solves the problem.

Anyway, I keep here updating with news.

THANK YOU!

[abyss]

IMO this level of marks on lens should NOT affect your cutting strongly. Beam for 80W is a usually ~ 4-7 mm in diameter, say 5.5mm average. If you have set optic well it should hit center of the lens. Moreover, there was people who had even cracked lens in half (!) and laser was still usable, so they can cut material when was waiting for new lens (not me, I have spare lens). Your lens maybe is not absolutely perfect, but can not have so big influence on cutting. I will say - poor tube or (less probably) faulty power supply. Only way to check what is going on is checking real beam power.

[sehio]

IMO this level of marks on lens should NOT affect your cutting strongly. Beam for 80W is a usually ~ 4-7 mm in diameter, say 5.5mm average. If you have set optic well it should hit center of the lens. Moreover, there was people who had even cracked lens in half (!) and laser was still usable, so they can cut material when was waiting for new lens (not me, I have spare lens). Your lens maybe is not absolutely perfect, but can not have so big influence on cutting. I will say - poor tube or (less probably) faulty power supply. Only way to check what is going on is checking real beam power.

Thank Abyss, I will buy Mahoney Laser Probe.

[sehio]

Hi ppl!

I have just tried my new PSU and still the problem. Mahoney laser test is coming. Anyway, I realised that putting a piece of plywood at the end of tube and doing some power tests, I can find this:


what do you think?

[KH0UJ]

On my opinion your laser tube is getting weaker, we have 3 laser machines in the shop and consumed more than 50 tubes in a time span of 8 years, I noticed if the tube is getting weaker the laser beam will get funky, sometimes doubled, sometimes getting bigger laser beam, sometimes if you set it to full power it gets weaker.