Problems with china laser

[Ralph Morehead]

I have a 100 w laser I purchased off ebay that came from china-cnc-zone. I have had it a couple years and it has worked great. Untill Now.
The problem is that the power setting is changing while its cutting. It has a led display for the power and a series of buttons to change the settings, such as ( +10% , +1%, -10%, - 1% ) and so on.
If I start it at 15% it will cut for 5 to 10 minutes and then jump to 50 or 80. If I change it back it will eventually jump back up. So I've ruined a few projects.
Other then that it seams to be working ok . the power seams to correspond with what the power on the display says.

[Bert Kemp]

were thinking on it:D

[Ralph Morehead]

To give an update I figured out the problem , I hope this will help anyone else having this problem.
The other day I decided to go threw all the wiring for any problems. As I was checking I remembered that the red dot pointer had quit awille back. As I was looking at it I noticed a little wire poking threw the flexible conduit. both the red and black wire were broke about 6" from the head.evidently as the head was moving back and forth the wires would short out, thus messing up the power setting.So for now I simply disconnected the wires from the power supply , and it works fine.
I will probably pull the wires out of the conduit cause there is some wear on the air tube from the wires rubbing on it. Being close to the head is where most of the movement is on the conduit and its a little tite having two wires and the tube all in the conduit. I've gotten along this far without the red pointer light so I'll probably wont worry about it.

[Ian Stewart-Koster]

Well done figuring that out, and thanks for the update.

[John Lifer]

YES! In addition, if you have a auto-Focus on the head, that power will ALSO short out the whole system.