Laser fault

[Kieran Mannings]

Hi,

We have a chinese laser brought in the UK, which is a 1200X900, like here:


When you ask the machine to run a program it randomly stops moving from left to right. If you turn the machine off and on again then it seems to work OK but only for a matter of minutes until it stops moving from left to right again.

The supplier of the machine wants a fair bit of money to look at the machine, we would therefore be keen to hear if anyone has had a simular problem or knew of a likely cause.

Hope someone can help.

[matthew knott]

Does it do it with all files or is it just one specific one you have, that would be the first thing to check.
Next, I'm not sure how these machines work, I assume the machine has memory and the file is sent to the laser, if it just has a buffer then it could be the computer USB connection is dropping out, if not it could be a faulty main board that's locking up. These machines are pretty simple so there cant be a massive amount wrong with it. DO the usually check all the cables, reboot the pc and maybe re install the drivers and see if that helps
Cheers.

[Kieran Mannings]

Hi Matthew,

Thank you for your help, I do not have the machine on site so I have relayed your suggestions, the machine has a memory so a job can be stored on the machine rather than being sent down the USB cable during operation. I will get all that you have suggested tested, thank you for your help. If there are any further sugesstions they would be much appreciated.

[Alexa Ristow]

Hi Kieran,
I would suggest that you try and isolate a logic error from a hardware issue.
most chinese machines have separate stepper motor drives for the x and y axis. Set up a file consisting of a square that fits easily in the centre of your machine. Maybe 50% of bed size. Set origin to the middle ofthe square and move the head to the middle of the machine. When you run the file, the head should then more freely withinthe confines of your bed and return to the centre ofthe machine when completed. Run this cut until you experience failure. Switch off and then swop the cables that run from the stepper drivers to the actual steppers themself. restart machine and run the testfile again until failure.
If the failure remains on the same axis, then the stepper motor could be at fault. next step would be to isolate the actual stepper drivers by swopping back the stepper cables and then swopping the cables from the DSP to the controllers. Same logic.. if you know the y axis is functioning, then eliminate the hardware elements ofthe x axis by working backwards to the DSP.

Cheers.

[George Carlson]

Most of the Chinese lasers use the Leetro 6515 controller, some use the faster 6535. In any can you can buy a controller board directly from Leetro. Check out you power supply first to make sure it is putting out the correct voltage. Power supplies are a common source of problems. Other than power supplies, motor drivers, and controllers, there's not much to a laser engraver.

[Kieran Mannings]

Thanks for your help guys!