I know this is a long shot as this feed over 3 years old but i need some help i think my tube has gone just received this k40 from Facebook so no warranty no matter what power percentage i run at it only puts out 4-5 amps will attach a video here is a link as video was too big.
Your best bet to troubleshoot is to read the FAQ and K40 intro at the top of the page. After you have gone through the info, let us know the outcomes. We are here to help but need as much info as possible.
Are you having a problem i.e. why are you asking if the tube is good?
Start by posting:
Pictures of:
@harrison_fletcherpri there is no way to tell if a laser tube is good or bad just by looking at the tube while you fire it. And the fact that you are reading off percentages tells us you probably have one of the K40 machines which has what is called, a digital display. THAT in and of itself is a problem and as @HalfNormal mentioned you can learn all about by reading all about the K40 in the K40 Intro linked at the top right of this page. Or also: Don's Laser Things: Understanding the K40 Digital Control Panel???
@donkjr is great at troubleshooting and evaluations so if you can do what he asked you’ll end up knowing not only the condition of your machine but all the ways to fix it and get it working well and staying that way.
Thank you all and will go through it on my next day off working like mad atm and will post videos/pics then hopefully its not the tube cheapest one i can find is about £100
The tube is a consumable, so even if it isn’t the tube that is bad now, you should expect to replace it at some point. That price is in the typical range. As @HalfNormal said, make sure to read through the K40 Intro at the top of the page. It, and the other articles in Getting Started with CO2 Lasers, are really important to understand, both for what to expect to spend to operate a laser cutter and for how to operate it relatively safely.
The good news is that in that tube replacement price range, you should reasonably expect a better-than-new tube, because the K40s usually ship with tubes that aren’t that great in the first place.