My chinese laser cutter is faulty and no one is able to help, I am desperate

[Abdalla Safwat]

Hi, I will try to be brief as I can with my problem and I would really be grateful if you would help me with the troubles I am facing in the machine until it gets resolved hopefully.

I do have several problems in my machine:
The lines are wobbly and wavy in high speeds especially in the horizontal lines
The machine recently have been freezing, stopping before the order starts and I have to restart the machine so it would function properly
The LCD screen is acting weird


Let me talk about the issues from the last to the first as the first is the one that takes longer to explain, I need to say at first that I just started working the machine 1.5 months ago, didn't exceed 10 hours of work, I am from Egypt, I have no proper maintenance for the machine from the exporters who bought it from china, I paid around 7500$ for that machine as prices here are extremely expensive for anything and basically I am stuck with it. It is a 160x100cm machine, it is 100W which is probably 80W really.

The LCD Screen:
The LCD freezez, looses all the data on it, sometimes even flip horizontally, does weird things when the order is running, I send it from the pc or I re-run it from the machine, it happens over and over again. I contacted the maintenance guy, he told me to connect the pc via a stabilizer, I did, nothing has changes and the LCD still goes crazy, whether I press Esc, or any other button, nothing happens, it functions sometimes but with the weird looking screen, I have to restart for it to be proper again.


The freezing of the machine:
I have noticed lately that sometimes randomly the machine would stop in different ways, either in the middle of an order and I have to restart and it asks me to resume, or it starts an order and immediately freezez with a loud noise as if the motor was stopped forcefully and the keypad wouldn't work, the arrows wouldn't work and I have to restart again, or it would just send orders with wrong layer colours and data, I have to restart for it to read properly the files, I contacted the maintenance guy he said that is a virus on the drive and I should delete every file on the machine and it will be fine, and that I should replace my new bought pc that I just got 1.5 month ago as it might be faulty.

The wobbly lines issue: The main pain in the gut
Attachment 340332I have noticed at high speeds a wobbly line that doesn't seem right, I made my research and contacted other people and the maintenance guy and didn't yet be able to resolve the issue. First of all I was told it might be the lens not held tight, I have never opened the nozzle before for cleaning so I wanted to do that, I found the lens shattered from the side, the center is fine and that's why it still cuts and works but 3/4 of a lens

I reinstalled the lens again and tightened properly and ordered another lens and still waiting for it to arrive, and tried again, still the same problem, I was advised to make some tests on different speeds, 50, 150, 300mm/s, so I did with the provided file and attached a link to google drive for all the results, in 50 it was a bit wobbly and it increased with speed especially when I draw letters, numbers, small shapes with lots of different paths, it still appears in circles and squares as I go smaller in size. To clarify this is for drawing which is Cutting in a high speed and low power, not engraving. I also noticed the waviness is tiny in cutting at low speeds but it is like teeth, not easy to notice for others but I can clearly see it (photo name: cutting wobbly teeth) I was told it might be a mechanical problem and here I started exploring my machine more (photos attached of the interior of the machine, belts, wheels, step motors, everything in case you need to check something) I tried holding the belts and comparing left to right, it seems the right equal tension, the laser head is not loose, the couplings and wheels are not loose, the lens is tight now, also I attached a felt tip pen to the laser head by tape to check if the problem is with the beam, lens, mirrors, and still the same problem ( attached an image for the pen where it was attached, and a piece of furniture that I keep testing, it is drawn in a floor plan where is wobbles and shows weird looking shape) I tried before that tightening the mirrors and realigning them. I was then advised to check the X and Y drivers and see the settings for the current, I was told to increase the current of Y a step if I found it to be equal in the same settings as the X as it is a heavier axis so I did and tried, no change whatsoever. Of course at the very end I called the maintenance again and he told me, I should buy from them another lens and the problem will be solved and if I didn't then it wont be fixed.


Sooooo, I am not sure what to do, I tried to wrap up the whole last 3 weeks, maybe I missed something, please ask if something I haven't mentioned, I will. I will put a link to the whole folder of images in my google drive of the machine so you can study well and maybe get back to me in case you found any solution. I use corel draw extension to send the files to the machine through usb cable, sometimes I use RD Words but I think it messes up the files already, so mostly I do use Corel Draw.

I attached all the images for the lens, wobbly lines, tests, everything.


The link to all the images:
https://goo.gl/QbQjrL

I really hope you can help

Best Regards,
Abdalla

[Bill George]

Let me guess you got it off eBay? If so I would contact the vender through eBay and try to resolve the issues. In the mean time I would check all the plugs, connectors and connections on the machine.

[Rodne Gold]

Could be a grounding problem .. make sure the machine grounds are all tied up to a good earth..

[Bill George]

Are they also running 220 volts? I don't think there is a ground ran like US requires. So that would be very likely, he could have a grounding issue.

[Abdalla Safwat]

Let me guess you got it off eBay? If so I would contact the vender through eBay and try to resolve the issues. In the mean time I would check all the plugs, connectors and connections on the machine.


I got it off a company that imports chinese machines here in Egypt and all they say change the lens and everything will be fine, and of course I don't know the origin of the machine in China


As for the grounding, I did the grounding myself, I am in the ground floor, I took off floor tiles and dig 3 feet below and filled it with coal and coarse salt in a pipe and passed through it a red copper rod that is 10mm thick, until it reached the surface and connected it to the machine, we don't have grounding in Egypt so this is the best I can do myself.

[Kev Williams]

Your machine's brain is on drugs... ;)

Every bad cut piece I saw in those pics are identical. Every bloop, dip, dydoe, bump, jump, wobble and hop is the exact same on each piece. This means the stepper motors, and the machine, are doing exactly what they're being told to do.

This eliminates mechanical issues as the problem. And with mirror imaged panel display thrown in for good measure, that pretty much seals the deal in my mind that this machine has a controller that's complete trash, or maybe, if so equipped, the dip-switches are all in the wrong positions...

My money's on controller is complete trash. And the last person I'd call for help is the 'maintenance guy', as it's obvious he wouldn't know a dip switch from a French dip.

[Bill George]

The ground rod should be either a iron or copper pipe down 6 ft but it needs to be in moist dirt or sand. If the water line coming into the building is metal you could also use that. Someone else suggested controller, before I did that I would fix the ground and look for loose connections. Find a Ham, amateur radio guy, they know about ground rods.

[Abdalla Safwat]

Your machine's brain is on drugs... ;)

Every bad cut piece I saw in those pics are identical. Every bloop, dip, dydoe, bump, jump, wobble and hop is the exact same on each piece. This means the stepper motors, and the machine, are doing exactly what they're being told to do.

This eliminates mechanical issues as the problem. And with mirror imaged panel display thrown in for good measure, that pretty much seals the deal in my mind that this machine has a controller that's complete trash, or maybe, if so equipped, the dip-switches are all in the wrong positions...

My money's on controller is complete trash. And the last person I'd call for help is the 'maintenance guy', as it's obvious he wouldn't know a dip switch from a French dip.

How will I be able to check if it is the controller or the dip-switch (I don't even know what are these) is the problem, and If I knew, what steps do I take to solve the problem?
Is that also the reason why the machine is freezing and the LCD thing or that is for the faulty cutting and speed drawing only?

[Keith Winter]

How will I be able to check if it is the controller or the dip-switch (I don't even know what are these) is the problem, and If I knew, what steps do I take to solve the problem?
Is that also the reason why the machine is freezing and the LCD thing or that is for the faulty cutting and speed drawing only?

Contact your maintaince guy and ask for the proper dip switch settings. They are the little switches on the side of the controller boxes. He should know what they should be set to. If it's the controller try reloading all your software on the controller in case it got corrupted and then if that doesn't work then you will need to try a new controller (I assume it's still under warranty?) Alternatively you can look at the controller and type the model # off of it into Google and search for the manual to get settings, if that fails you can buy a replacement yourself to try. Once again if it's new, the person you bought the machine from should pay for this.

The lcd screen you mention freezing is the controller it's possibly that, or the main board (which is connected to that if you open the case), or the grounding. If you were improperly grounded it would freeze and such, and appear to be broken like you are describing. Or as Kev said it the controller or could actually be broken.

First thing I would do is hire an electrician to come in and properly ground that thing before you get a nasty shock, might fix all your troubles.

[Steven Resnick]

It looks like your Laser is from Thunder Laser.
http://www.thunderlaser.

They are a very good company to work with.
I have the Nova 35 and I'm very happy with it.
I dealt with Yumiko and she was great.

Good Luck
Steven

[Rich Harman]

The wavy lines at high speed cutting is normal. Or at least the ones that I saw are. These machines are not meant to move that fast. Whenever the laser head has to change directions abruptly there will be a bit of wiggle as the sudden deceleration-induced oscillations dampen out. The higher the speed the greater the effect.

I start to notice these wiggles when the cutting speed is over 20mm/sec. At 50mm/sec they are very noticeable. It seems your lowest speed is 50mm/sec. You are running your machine waaay too fast.

[Kev Williams]

if 50mm is too fast, something is wrong--

watch this video... https://youtu.be/MQc5IJiZBfs

[Kev Williams]

Since I'm a crappy cameraman who can't hold still, here's some pics of the cuts-
340446340447

I did end up with some bumpy tight curves at that speed,
but there are settings that can be changed to slow the speeds
it cuts the curves. (the trick is finding them!)
340448

If your machine can't cut smoothly above 50mm/sec then there's
likely a mechanical issue; loose cog, belt too loose or too tight, etc etc...

The OP's issue isn't mechanical. It's a bad data issue. The machine is
doing what it's told to do, but whatever's doing the telling isn't doing it right...

[Rich Harman]

If your machine can't cut smoothly above 50mm/sec then there's
likely a mechanical issue; loose cog, belt too loose or too tight, etc etc...

The OP's issue isn't mechanical. It's a bad data issue. The machine is
doing what it's told to do, but whatever's doing the telling isn't doing it right...

The OP is cutting at 50, 150 and 300 mm/sec. That's beyond the capability of my machine, and his appears to be similar to mine. Someone show me a large Chinese machine cutting cleanly at 300 mm/sec and then I'll believe it's not a mechanical issue.

[Keith Downing]

if 50mm is too fast, something is wrong--

watch this video... https://youtu.be/MQc5IJiZBfs

I was thinking the same thing. Maybe he meant 500 mm per second? I know 400 mm/s is the cutoff for many chinese machines to run reliably. At least that's what I've been told.

But keeping it under 20 mm/s?? High quality rastering of large areas would take days at that speed. So I can't imagine that's correct.

[Dave Sheldrake]

One of your mirrors is loose

[Jerome Stanek]

I don't cut at 300 mm but I will run it at that speed to cut paper to make sure it is cutting correctly

[Keith Downing]

The OP is cutting at 50, 150 and 300 mm/sec. That's beyond the capability of my machine, and his appears to be similar to mine. Someone show me a large Chinese machine cutting cleanly at 300 mm/sec and then I'll believe it's not a mechanical issue.

Now you've got me curious. I just assumed the machine would function normally at the same speeds whether cutting or rastering. But, of course, with only a 60 watt tube I always cut at 10 to 25 mm per second to make sure I get through the material in one pass. Sooo, maybe you are correct in your assumption after all.

I'm curious enough now that I'm going to do some testing later this weekend to see how my machine handles cutting paths at speeds over 50 mm/s. Obviously there isn't much I'll actually be able to cut at that speed, but I should be able to see a nice burn line.

[Dave Sheldrake]

My chinese boxes are run at 130mm p second cutting on 2mm mdf and don't lose the corners, any more though and stuff gets funky. A lot depends on the mass of the gantry and laser head. More weight = harder to change direction

[Keith Winter]

I was thinking the same thing. Maybe he meant 500 mm per second? I know 400 mm/s is the cutoff for many chinese machines to run reliably. At least that's what I've been told.

But keeping it under 20 mm/s?? High quality rastering of large areas would take days at that speed. So I can't imagine that's correct.

-Keith Kev and Rich are talking about cutting, you are talking about engraving. 50ms is way too fast for cutting anything aside from paper or something very thin. Possibly beyond his machines specs for cutting.

[Keith Winter]

My chinese boxes are run at 130mm p second cutting on 2mm mdf and don't lose the corners, any more though and stuff gets funky. A lot depends on the mass of the gantry and laser head. More weight = harder to change direction

Thats really fast! imagine where it looses it after that is curves? Rich at Trotec was explaining to me all lasers loose precision cutting when going fast on curves, the faster you go, the less perfect a circle or curve will be.

[Dave Sheldrake]

Thats really fast! imagine where it looses it after that is curves? Rich at Trotec was explaining to me all lasers loose precision cutting when going fast on curves, the faster you go, the less perfect a circle or curve will be.


yup, physics 101, mass x velocity = energy...twice the speed = 4x the energy and yep, corner wobbles when it goes. Bit like drifting a motor car round a corner...all that energy has to go somewhere

[Bert Kemp]

I'm baffled what are we cutting at these speeds:confused: saran wrap? I cut 1/8th BB at 12mmps I cut thin paper at 60 mmps if I went faster all I would get is a light brown line on the wood.

[Scott Marquez]

I cut Cordura fabric on my machine, and normally cut at 125 mm without loosing the corners. I also have preset speeds built in for circles based on their radius. Maybe the OP needs to modify his corner speeds and acceleration settings.

Scott

[Kev Williams]

Ok....

below is a link to a video of my 1300x900 Triumph happily cutting thru 1/8" cardboard
(in the pics I posted above) running @ 300mm/second and 60% power.

>>>>> https://www.youtube.com/watch?v=MQc5IJiZBfs <<<<<<<<
^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^

^^^ is because I already posted the link once but seems no one noticed! ;)

My machine's max Y axis speed is 300, so I felt no need to go faster. And as I noted in
the pic post, I did get a few bobbles in a couple of the tight roundy's.

And as Scott noted above, curve speeds are adjustable on these things! As are the power settings for
when the machine does slow down.

I've been playing with speed settings since shooting the video this morning.
And the changes I noticed in cutting speeds were pretty substantial. The settings I changed were:
Space speed -from 500 to 300
Space acc -from 2400 to 1200
Min Acc -from 600 to 400
Cut Acc -from 2400 to 1200

Space speed is when the laser head moves but the laser ISN'T firing, going from the end of one cut to the beginning of the next cut...
Lowering the space speed lowers the maximum space speed,
Lowering the space acc speed decreases the accel and increases decel rates- meaning it takes more time to reach max space speed,
and also starts slowing down sooner. All of this helps with the inertia thing Dave talked about...

Now, lowering the Min Acc speed seems to affect the slowdown the process of cutting curves, or other shapes with nodes in close proximity.
And lowering the Cut Acc speed seems to affect the accel and decel rates when cutting long straights, and works like the Space ACC
speeds, taking longer to reach full speed after leaving the last point to begin a long straight, and slowing down sooner when approaching
the next point at the end of the straight-

Again, this helps with the inertia thing--- big time!

I ran the same test as before, and also added a 10" x 2"-ish rectangle, but with half-round ends. All of the smaller parts
cut noticeably slower than before, but on the new round end rectangle, it reached full speed on the straights, but instead
of flying around the half circles like it normally would, the machine slowed WAY down to do the round ends. It very much
resembled how my western lasers slow way down for curves.

Also-- I assume most Chinese lasers have low and high power cut setting like mine? The low setting is for approaching
corners and slowdown cuts. And I was watching the power meter, and it dropped as I'd hoped during the slow downs...

These machines shouldn't have to be slowed way down, wasting time making sloooowww straight cuts
just so the precision of curve cutting doesn't suffer.

I want to shoot before and after videos with the old and new settings, but it's near midnight so maybe sometime tomorrow :)

[Dave Sheldrake]

^^^^ Yup, Kev's spot on

[Dave Sheldrake]

I'm baffled what are we cutting at these speeds:confused: saran wrap? I cut 1/8th BB at 12mmps I cut thin paper at 60 mmps if I went faster all I would get is a light brown line on the wood.

2mm mdf @ 125mm ps is using a Dc GSI/SLC 240 watt tube

[Bert Kemp]

ok thnx must have missed the 240 watt LOL


2mm mdf @ 125mm ps is using a Dc GSI/SLC 240 watt tube

[Scott Marquez]

Kevin,
Your video is "private" so I'm unable to open it.
Edit to add:
OK, the link works now. WOW that thing is fast, thanks for sharing how fast these things can go, with some tweaking.

Scott

[Kev Williams]

Arrghh....

Ok, should work now... (I'm not a you-tube officianado obviously ;) )

https://youtu.be/MQc5IJiZBfs

[Kev Williams]

I have videos uploading, they're taking awhile...

And instead of hijacking this thread further, I'm starting a new one, 'speed change testing'... :)

[Bill George]

So whatever happened to the guy who posted this, is it running or not?

[leland huang]

Maybe it is also grounding problem of your computer, try to get your computer connected with grounding wire.

[Joseph Shawa]

The crooked lines are probably due to the focus lens in the cutter head not being held tightly. Make sure that the retaining ring is secure against the lens and shake it before you insert it.

As for the freezing is it happening in the middle of the table or near the edges? Even though the table has a listed size it may not be able to maneuver to all the points. Try to place the project to the middle of the table and do an immediate cut rather than using the coordinates.

Finally, make absolute certain that the 220V wiring order is correct at the plug where it is connected to the power supply. If it is not you will get voltage running through the machine to ground. To test if this is the problem measure the voltage from the power supply to ground when it is out of the machine. It is possible that they switched two of the wires at build time. My original power supply connection order was AC AC FG my new power supplies were ordered FG AC AC. Easy way is to make sure the two similarly colored wires are AC AC : )
The laser will still fire but the controller will act crazy.


Good luck