[Nickwit]

Hi everyone.


I've just changed the controller board on my machine - all good, but I now have a new problem, which may (or may not) be related.


The cut gets weaker after about 5 seconds.

So if I cut a long thin (pencil shape/size) slot in a piece of MDF, it'll go right through fine.... then it will get weaker and weaker, so by the time it has returned to its origin, it isn't cutting through at all.

This rules out focus, centering, dirty lenses/mirrors (all checked anyway) all the usual things - and leaves me thinking that the beam is getting weaker during the cut.


Is this a sign of a dying tube?

I've had this tube for a year or so. What does a dying tube do?

[GWKlaser]

Hi Nickwit

I am afraid you need change your laser tube. it gets old.

how many walts of your laser tube ?

Abby

[g.weike laser]

hi,
yes,abby is right,you need to replace a new laser tube,eventhough you didn't work on many hours,as without working,laser power also leak.

[Nickwit]

Hiya - it's 60 watts RECI

[GWKlaser]

Hi Nickwit

RECI company has not 60W laser tube. they manufacture 80W and above.

I think it is other brand. With shorter lifetime.

you need replace a new one now.

if you want upgrade to 80W RECI laser tube. add another 80W power supply is ok

80W RECI laser power can up to about 100W. this can make your work easier.

Hiya - it's 60 watts RECI

[Nickwit]

Ah - that will explain why I had so much trouble finding a replacement

I went for another 60 - probably should have gone to 80... maybe next time.

[Nolan Yang]

Hello Nick, how long the laser tube work everyday?

[AmyThunderlaser]

Ah - that will explain why I had so much trouble finding a replacement

I went for another 60 - probably should have gone to 80... maybe next time.

here we have an lesson to guide you how to replace a new laser tube:
How to replace the laser tube
hope it can help you some or less.
good luck.

[Allycat]

Hi, Have you checked the mirror alignment?

[scrappyjedi]

Power dropoff can definitely be a sign of a bad tube. In fact, in my experience that's the root cause most of the time, but every once in a while it's not.

A few things to look at:

- How does the plasma/beam look in the tube when firing? Is it white or a bright pink or purple? My 40W tubes glow a deep purple (like Mace Windu's lightsaber) when they're working properly. When they're dying, they shift toward bright white. Also look for a mode change within the beam. Does it visibly change size, color, or even position within the tube when running? On a stable tube, the beam should not change form or color while power is being applied (a little dancing around near the output end is normal).
- What temperature is your cooling water? Heat will kill a tube very quickly, and power will also drop off as tube temperature rises. We keep our coolant water at 60 degrees F using a lab chiller. (With your power dropping off so quickly, though, I wouldn't expect this to be the issue.)
- Do you have a meter measuring current from the high voltage supply to the tube? If so, observe whether or not the current is stable, or whether it too drops off as your laser power diminishes. If current is dropping off as power does, then you likely have a dying HVPS and not a dying tube (though I have had both go at the same time before).

[AmyThunderlaser]

- How does the plasma/beam look in the tube when firing? Is it white or a bright pink or purple?

normally it should be purple while laser firing,
if laser tube die (gas leak), it's while,