Loss of power after running for 2 hours?

[Joe Peacock]

I am running my ULS VLS2.30 nearly continuously during the day. It is cutting for about 45 minutes out of every hour and the other 15 minutes is spent replacing the material to be cut. I change material about every 12 minutes. I have noticed that after about 2 hours the parts aren't cutting the same. Where I was getting good clean cut through's at 8:00 I am getting partial cuts around 11:00. When I come back after lunch and start up again I get good cuts and then a couple of hours later things have changed.
Do lasers loose power the longer you run them?
Joe

[James Jaragosky]

I am running my ULS VLS2.30 nearly continuously during the day. It is cutting for about 45 minutes out of every hour and the other 15 minutes is spent replacing the material to be cut. I change material about every 12 minutes. I have noticed that after about 2 hours the parts aren't cutting the same. Where I was getting good clean cut through's at 8:00 I am getting partial cuts around 11:00. When I come back after lunch and start up again I get good cuts and then a couple of hours later things have changed.
Do lasers loose power the longer you run them?
Joe
Sounds like a heat soak issue.

[Joe Peacock]

James,
Is this something inherent in the system or something that can be cured?
Thanks,
Joe

[Bill Cunningham]

The back to normal after lunch 'does' pinpoint a heat related problem.. Your blower may be too small, there could be some obstruction in your airflow over the tube. Turn off your machine, and blow the dust out/off the laser tube area, see if anything is partially blocking your exhaust. If you are using a shop blower, pull off the intake pipe and see whats stuck to the 'keep your fingers out' grid. I had a whole layer of stuff built up on mine when I checked it, I then cut the grid out to prevent future blockages.. After cutting for a while, feel the tube and see just how hot it is..

[Rodne Gold]

Also check your optics and mirrors , if there is gunge on em or the mirrors are dulled , they heat up and the expansion on mirrors cause them to misalign the beam and very small movements in the mirrors add up quickly.

[Tania Duper]

Good points raised, heat and optics. I'd also question the surrounding temperature. Heat sinks draw the heat, but the heat has to go somewhere or else the sink heats up and stops sinking more heat.

Since your tube is in a cabinet, the cabinet temperature will go up and the heat sink will not work very well. That is why lasers have room temp requirements so the heat sink fins can be cooled off by the room temp.

You should run the A/C in that room to keep it at the low end of the suggested temperature range that's recommended by the manufacturer and see if that enables you to run longer. Of course, a more powerful laser will have better cooling as it's intended to generate a lot more heat. For those who haven't purchased yet, always go for as much power as you can afford.

[Dan Hintz]

Joe,

I'm assuming this is a relatively recent model of VLS, with the fans above the cartridge? (Bill, I'm asking because none of the more recent models by ULS use the exhaust fan for cooling)

Make sure those fans aren't gunked up with lint/dust, and run a cloth/Q-tip between the fins of the cartridge's heat sink if there's dust in there (not likely as those fins are spread far apart). Rodney has already suggested checking the optics, and I'll add to check the alignment... if your beam is hitting the lens/mirror carriers, even by a small amount, a slow buildup of heat will lead to further misalignment.

[Joe Peacock]

I am running in a room cooled to 70 degrees. I will check everything suggested.
I really appreciate your inputs.
Joe

[Scott Shepherd]

Joe, forget checking all that stuff and reporting back. Pick up the phone and call ULS. It's free, they are professionals as trouble shooting it, and you'll probably have an answer before the weekend.

That's what we pay them for, use their services.

[Joe Peacock]

Joe, forget checking all that stuff and reporting back. Pick up the phone and call ULS. It's free, they are professionals as trouble shooting it, and you'll probably have an answer before the weekend.

That's what we pay them for, use their services.

I will give them a call Monday!
Thanks,
Joe

[Scott Shepherd]

They are still open NOW!!!!!!!!!!!!!!

[Tania Duper]

I'm sure Joe had something else to do toward the end of the day Friday while they were open...

It's still good to check the things people suggested as their customer support is likely to ask him to check as well. If we all flood CS departments with issues we can resolve on our own, they have to hire more people and prices of equipment go up. Plus, nobody wants to sit on the phone for 2 hours with CS going through the basics so a lot of time can be solved by telling them the things you've already checked.

[Scott Shepherd]

Tania, would you rather take advice from people that don't own the machine and have never seen the machine, spending hours going through all their general suggestions, or pick the phone up and call the people that made it and support it and get it resolved. Resolution for a technical issue, if it's going to involve replacing parts is delayed by not calling them. The problem was brought up on 2/18. If the call to ULS would have been made, they would have had parts there on 2/19 in the morning. You could have been running by afternoon.

However, now we're on to calling on 2/22 and getting parts on 2/23. So that's how many days of possible lost production or lost product due to poor cutting. Maybe that time isn't important to you, but to people like me that make a living from the laser's work, I can't afford to be down that long without losing customers.

[Rodne Gold]

Scott , seems to me that this problem is not machine specific and the solutions offered as to cleaning dust , fans ,filters and optics would not be time wasted
Even if they dont cure the current problem they are very good preventative maintenance especially with heavy duty usage.
We are only trying to help Joe...

[Scott Shepherd]

Rodney, I don't have any problem with people trying to help. I think it's great, but it drives me nuts when people spend days coming on the forum saying "my machine isn't working right and I don't know why".

PICK UP THE PHONE!!!!!!!!!!!!!

I don't mean to pick on Joe, but there have been people in the past that have spent 2 weeks on the forum with their machine not working properly and no call to tech support.

If you talk to the tech supports, they will tell you that it drives them nuts as well and they can't understand why people wouldn't call them. That's what they are there for.

You can't use the excuse "Well I have a full time job and do this on the side" because they are all open from early in the morning to late evening.

I agree, lots of great advice has been given on this thread and all in efforts to help Joe resolve his problem. I'm just trying to add to that in saying "there's no need to guess, pick up the phone and call the people that know and can help you resolve it".

[Rodne Gold]

I'm sometimes guilty of doing that , I first try to work out a solution myself most of the time before phoning tech support ...I suppose its the same thing as fiddling with stuff before reading manuals or refusing to take directions or reading assembly instructions :)

[Scott Shepherd]

Rodney, I enjoy figuring stuff out too, but in the end, I'm in business to make money, not fix my laser. I think one thing I fail to realize more often than not, is that many people posting in this forum do not depend on their laser to make a living. That's puts them in a very different situation than I am. I can't spend 10 days with no machine. Some people can and don't mind it.

My belief is that I paid for support and I'm going to use it. If you don't use support, then when they lay off 1/2 of the support group because no one calls, who will be left when you do need them? :)

[Bill Cunningham]

By using a quick check of your machine, Optics heat, dust buildup, smell, etc; 'before' you call tech support can save both parties a lot of time.. When my x motor went, the tech was having me check the controller board on the back, until I said the smell was coming from the right side of the gantry, which pinpointed the motor as the problem. This simple little observation saved both of us a bunch of time..
Does ULS have a 800# and foot the bill for maybe a two hour call? I doubt it, so a quick check of the obvious will save everybody, even if it's only a phone bill...

Look on the bright side, at least (right now) we are not being hooked up to some tool in Mumbai who's first question is: "Did you check to see if it's plugged in? ":D

[Paul Brinkmeyer]

Look on the bright side, at least (right now) we are not being hooked up to some tool in Mumbai who's first question is: "Did you check to see if it's plugged in? ":D

Hey now, I'm not from Mumbai, does ND count, but one time when I was sent out on a service call to fix a brand new computer system that stopped working, I found the power cord unplugged....it seems the "operator" did not think it needed two plugs into the monitor and wanted to save power by unplugging one.

[Bill Cunningham]

Hey now, I'm not from Mumbai, does ND count, but one time when I was sent out on a service call to fix a brand new computer system that stopped working, I found the power cord unplugged....it seems the "operator" did not think it needed two plugs into the monitor and wanted to save power by unplugging one.

Ha.. 'sometimes' the 'tool' is on the operator end...As long as you showed him where the 'any' key is, and fixed the printer mouse..;)
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