Jiachen laser

[Anton D]

Hi Guys.
have any of you had any experience with Jiachen machines. My model is a JD 6040SP 60w. The mchine has worked flawlessly since 2007 But have just run into a problem. The head has always tracked smoothly but now when the head moves on the Y axis it jumps so violently the whole machine shakes (it weighs 600kg!). Also does anybody have the gms file for the 2007 version of the laser process software for this machine.

[zax15uk]

Anton, I believe that machine uses steppers. With the machine powered off (and if possible the motor disconnected) can you slide the head along the axis smoothly? If not, check the gears and belts for damage.

If so, the problem is most likely wiring or the motor driver (it could be an open coil in the motor but that is unlikely). The wiring should be easy to check, and if that's ok the motor driver IC (L297/298) or clamp diodes have most likely failed.

You can switch the X and Y axis cables to test it, if the problem moves to the X axis the driver is almost certainly the problem.

Zax.

[Anton D]

Zax
Thanks for the info, no the head does not move smoothly on the slides when the machine is powered down. I will check gears and bearings today. As a matter of interest do you think that the roller bearings and slides should be lubricated? I do not seem able to get a straight answer from the manufacturer!

[Pierke]

Hello Anton,

try to mail Cathy!

Pierke

[zax15uk]

If you mean, should you oil the bearings / slides?

No, the bearings are shielded and should have grease inside so oiling them is not necessary and can actually do more harm than good. The caveat to that is if they are open frame, or if the seal has worn and the grease hardened.

The slides should be cleaned thoroughly - if you oil them it collects dust and particles so regular maintenance is necessary.

Since the machine doesn't move freely it is also possible the one set of stator magnets have detached in the motor (maybe from overheating) causing it to run rough. If you disconnect the motor pinion you can see if the motor turns freely, this is a fairly common problem I see several times a week. The motor can be repaired but it probably isn't worth the effort.

Zax.

[rayscott]

I might be able to help.

Let's try to do some assumptions and find the solution

Given:
*The computer is not having problems.
*The laser machine is properly connected to the computer system
*The software is acting correctly
*The violent action is ONLY on one axis
*The laser machine hasn't been moved from building to building lately.
*The software and machine setup have not been intentionally changed.

Questions:
1) Is the laser system connected by USB or PCI control card?

2) Is the problem ONLY on one axis of the machine.

3) Is there any other large machine installed in your building recently?

4) Did you move some power wires near your controller board?

Suggestions:
*Move in only one direction at a time. Watch the axis that is acting correctly. It should move smoothly at slow and fast speeds.

*Run the machine at a very slow speed.

*Move the axis that is a problem.. at VERY slow speed is there still a problem? Increase speed in single direction.. does the problem still there? Is it much worse?


My suggestions for solutions...
1) Inspect the signal wires connecting to the stepper motor amplifiers.. and the same wires comming from the motion controller. You might have a very loose wire at one of those connectors.

*********
2) Inspect the wires going from the stepper motor amplifier to the motors. My experience tells me that one of the connectors has come loose. Be careful to notice that some of the plastic connectors could be fully inserted, but the pinching metal connector is not really tight inside the plastic connector. I found this problem a year ago with a cable on my Y axis. It took me 7 hours to fix.. I went through software, Motion controller, amplifiers.. etc. ..then bumped the connector while I was working to change out the stepper motor.

My opinion of the oil... Yes, I oil the linear ways. I advise to oil the ways on a very regular basis. Wipe the dirty oil off, then apply a very thin amount of oil. The pillow blocks must have oil inside them to work properly and for a long time. Without oil, the linear ways will rust and the ball bearlings will also rust. The linear pillow blocks should have a "wiper" or seal to prevent dusty oil from entering the bearings area. If you notice contaminated oil on the travel ways, then clean it and add new oil...

Ray Scott
www.scottware.net
3503 Carol Ann Lane
Middletown, OH 45044
513-320-2748

Laser machine sales in the USA
Check out our web site at http://www.scottware.net

[Anton D]

Ok here we go.
Under given assumptions all seems to be as normal and the machine has not been moved.
The laser is connected via usb, No new machine installed and the only power leads are the ones in the machines wiring loom. The problem seems only on the Y axis. I have checked all the controller connections, They are not push fit, They are all screw terminal and everything seems to be in place. I have inspected all the belts and they are all in good condition. The slides are lightly lubricated and the bearings are all sealed.
I have also removed the belt from the stepper motor and the motor seems to turn freely.
As a mater of interest on close inspection of the machine innards I think it was assembled by someone without opposing thumbs!! Why oh why did I not buy an American machine!!!!!
Pierke, I presume Cathy works for Jiachen, Do you have her mail, At the moment I am speaking to Tina and there seems to be a language barrier!

[rayscott]

Check your wire connections from the amplifiers to the motors.. you might have a wire loose with a wiggling connection.

Thank You,

Ray Scott

[zax15uk]

When you had the motor disconnected, and found it turned smoothly did you also check the head ran back and forth smoothly?

You said before it was rough, when all was connected so I wonder if that is still the case.

Zax.

[rayscott]

Let me check again...

* The stepper motor works smoothly when in hand.. unmounted from the axis.

* The mechanism moves smoothly when pushed by hand without the motor mounted.

* The axis jerks violently when run with motor mounted..


Do a small test... with the motor unmounted.. set the motor to a slow speed movement. Use your hand to push the axis around. Does your manual movement of the axis cause the motor to move in any jerking motion? I think that all this information tells me that there are some loose wires at the end of the axis where the motor connects to some cables..

Ray Scott
www.scottware.net
3503 Carol Ann Lane
Middletown, OH 45044

[Pierke]

Hello Anton,

i have PM you the adress from Hiachen Company and contact Cathy.

My experience with Hiachen and employes are verry good.
Don't ask to mutch question in one time. Better one question and one answer, and then repeat.
Succes,
Pierke

[Anton D]

The head runs smoothly on the slides with the motor disconnected and the motor seems to run smoothly when not mounted.The manual movement seems less smooth with the motor mounted but that may depend on your definition of smooth. I will check the wiring again.
Pierke, Thanks for the contact info, I to have always found them to be helpful. My problem at the moment is that they do not seem to believe that the machine can break down! I am sending them some video of the machine running.