Chinese laser 50W, 50x30cm - bad/good stuff, mods, problems etc.

[the.sniper]

Guys, just wanted to add to this thread. I recently acquired a 50w cina 50x30cm laser. (found it on Craigslist. dirt cheap)
Parallel to this find I was on path to rebuilding a china 40w smaller ebay unit. since getting the 50 w unit. I turned my attention to the the larger unit.

After getting the unit back to my home/shop I quickly did an evaluation. it needed several repairs. but in the the end I got it running quite nicely.
I had prior to this built my own chiller. Ill post up some pics. I have been following youtube/SarbarMultimedia for some time.
he has a ton of useful information to share. not to mention he is a splendid fellow.

What I have done to revive my 50 watter:
1: Replace the main DSP with a Lightobject LO-X7 (for no reason ther than i had it to install) the built in DSP worked.
2: clean/flush out the mystery tube. it was full of trash and clogged up.
2a: machine and install new water jacket fittings as the metal ones were corroded and fell off. (my repair on the tube was a 100% success)
3: check and align the tube/mirrors lens and head. I completely followed Russ's method and felt it was fool proof and easy.
3a: in doing so I had already constructed/devised a laser pointer to use for the alignment process. Then found Russ's youtube post.! go figure!
4: Replaced the water flow sensor. (it was bad) and some fittings.
5: Plumbed in my chiller.
6: constructed my own blower/air evacuation setup. (same as Russ's) it works perfectly.
7: Built a rolling stand out of aluminum to hold said laser and components.
8: Ordered and waiting to arrive a 45w laser tube 1000mm from LO. the current one is 860mm? +/- gussing its a 35/40w max tube?
8a: while the tube fires cleanly and is very pink while firing I wanted more power.
9:replaced the limit switches with mechanical micro switches.
10: added a Amp meter.


Things I built along the way.
1: Laser alignment thingy for aligning the mirrors.
2: Height gage for setting and optimizing the head/lens height.
3: Acrylic targets for easy alignment of mirrors (see Russ's posts)
4: redesigned Laser tube mount for newly ordered 45W co2 tube. Ill post pics of it too.

Things I want to add.
1: a motorized Z table lift. it already has the knurled hand knob on the lower right. I just need to add a DC motor with a reversing switch
2: water temp sensors In and out.
3: Emergency off switch.
4: a larger window or redesign the main door.
(to be added)

I'll stop here.
-Sam

[iuliusdobre]

Hi Sam,

Thank you for sharing!
Please, could you detail the replacement of the limit switches with mechanical micro switches?
Besides the replacement, you made any other change? What type of mechanical switch did you use?

[Storen]

///Replace the main DSP with a Lightobject LO-X7 (for no reason ther than i had it to install) the built in DSP worked.///

Sam,since you have experience with both RuiDa and Lightobject controllers, could you please tell how they compare? The advantages and disadvantages you've noticed.

[the.sniper]

Hi Sam,

Thank you for sharing!
Please, could you detail the replacement of the limit switches with mechanical micro switches?
Besides the replacement, you made any other change? What type of mechanical switch did you use?

See here for pics and info. Laser 50W 500 So many pics I just uploaded a slew of them... Ill get the switch part number. But if memory serves me well I ordered a hand full of Misc switch for some project years ago and the two I used was in a an assortment of 5? not use full information. but I was totally prepared to use some off the shelf micro switches same as the ones you can get at Radio Shack.

[the.sniper]

///Replace the main DSP with a Lightobject LO-X7 (for no reason ther than i had it to install) the built in DSP worked.///

Sam,since you have experience with both RuiDa and Lightobject controllers, could you please tell how they compare? The advantages and disadvantages you've noticed.

Storen, Sorry, but I dont have any real experience. though had I not had the LO-X7 on hand I would have just used the controller that it came with. When I got this used machine I did not get any software or techy info.
Knowing this I knew I might run into some difficulties. So I just used the LO-X7 I had purchased but not installed for my other smaller laser. I'm still pretty new/green wit the new controller but am glad to report any useable info I have.
S-

[RogerClark]

I have one of these machines.

So far the modifications I have made are fairly minor.

The laser tube clamps were absolute pieces of junk, made from a milled aluminium block underneath and some bits of hand bent steel over the top. (I will take some photos later and post them to sho just how bad they were).
The tube was aligned by packing 5mm thick bits of rubber underneath and on top of the tube, and on one side to push it backwards.

This made it very hard to align the tube, so I decided to design and 3D print my own adjustable brackets.

The other thing I have done is to buy a ventilation duct grill, which I am using instead of the bed of nails that other people use.
I got the idea from a YouTube video. At the moment I put the grill on wooden blocks on the main bed, but I intend to take out the existing aluminium sheet bed, and cut a big rectangular hole out of the middle, and fix the grill over the hole, so that air can escape straight down.

BTW, The grill is powder coated aluminium, but so far the powder coating is completely undamaged by the laser, jut just has smoke marks from cutting MDF.

The other thing I did was put duct tape at the back of the machine, so that the Y motor and drive rods etc, does not get smokey air passing over the top of it, and eventually everything would get a sticky layer of residue no matter what you are cutting.

Air flow is not that good, and I know some people fitted a more powerful external extractor fan in line with the exhaust tube, however the problem seems to be that there is not a good path for air to enter the machine. I find that if I leave the top open by about 1 inch, by placing a small block of wood, so that the top does not completely close, This greatly improves air flow.
But I have not done extensive testing to determine the optimum opening, as I could be 2 or 3 inches.

I recall someone tried removing the front access panel for the belt tension to improve air flow, but said it didn't help, but this may also be worth trying.

As I live in a sandy dusty area, I have also put stick on draft excluder strips around the opening of the laser tube cabinet. This has worked quite well, but I may need to buy some more expensive / heavier duty strips, as the lid pushes them sideways and I'm not sure how long it will be before the glue stops holding.


Other modifications I intend to do are...

Reroute the power for the fluorescent light as the wires take a crazy path through the laser tube cabinet

I need to increase the air assist flow, because my machine came with a lens with a 51mm focal length and the nozzle is 20mm from the cut, which means the aquarium pump that was supplied does not really deliver enough air to do much except keep the lens clean ;-)

[RHBlakeman]

Quick question for those of you with one of these 50W Chinese models, or had gone to DSP on your 40W - do the controllers all have the ethernet port but some dont put the external cable in by the USB ports? Can you send jobs to the unit via the ethernet like you would a laser printer? We are still wading through numerous vendors in the US, have found one with both the motorized Z and ethernet connection but have seen others with manual Z and no ethernet port outside but if the port on the controller is there and live I have plenty of parts to add my own external connector and later a switch and motor fo the Z table if I can get enough off to warrant not getting that model

[RogerClark]

Most seem to now have a cabled ethernet connection. mine has.

However I dont use it, as i consider it too dangerous, as these machines dont have any interlocks to prevent them operating when the top is open.

From USB you can start a job running, from the PC, and I think the same applies to ethernet, so there is no way Im hooking my machine up to the internet.
Even my workshop PC is not on the internet, I transfer files via memory stick, after designing on a high spec PC in my office.

These machines are not printers, you cant print to them from MS Word etc even if you connect via Ethernet.

You have to use RDWorks (aka several other names), so read your design files or images, and send those files to the laser ( or possible save the output file and transfer via ethernet )

Re:control

The basic models have manual Z control.

I know some people have replaced the Z motor with a large stepper motor and bought an additional stepper driver box and connected to the main control box, and I think this works.

But I dont know why you would want to do that.

I think you would also need an auto focus unit before you could make use of automatic z height

[RHBlakeman]

Most seem to now have a cabled ethernet connection. mine has.

However I dont use it, as i consider it too dangerous, as these machines dont have any interlocks to prevent them operating when the top is open.

From USB you can start a job running, from the PC, and I think the same applies to ethernet, so there is no way Im hooking my machine up to the internet.
Even my workshop PC is not on the internet, I transfer files via memory stick, after designing on a high spec PC in my office.

These machines are not printers, you cant print to them from MS Word etc even if you connect via Ethernet.

You have to use RDWorks (aka several other names), so read your design files or images, and send those files to the laser ( or possible save the output file and transfer via ethernet )

Re:control

The basic models have manual Z control.

I know some people have replaced the Z motor with a large stepper motor and bought an additional stepper driver box and connected to the main control box, and I think this works.

But I dont know why you would want to do that.

I think you would also need an auto focus unit before you could make use of automatic z height

You may not have gotten the point of my inquiry - I only wanted to know if the controllers all have the ethernet port so that if I get one without I can make a cable to add it. I am all too familiar with how printers work, netwoks, function, etc after many years of working on them. Even if I have the PC next to the laser unit my preference is network - not internet but local network. The furthest my PC would be from the laser unit would be 15 ft. I also understand quite a bit of how these function and while they are not specifically printers they function like a printer in that you have an X and Y axis moving a device around to create a marking on a material,. Vinyl cutters are similar as well. I have a 60" plotter and 36" vinyl cutter and I work on both of them. On the Z axis a motor would not be automatic but manual with a spring loaded switch that auto centers to off and has up in one direction and down in another similar to the way they come from China (though they use switches that wont return to off by themselves).

Anyway I was only curious if the port was common to all controllers and only cabled out to the exterior on some. After doing some looking at photos on listings of both machines and aftermarket controllers it seems they all do except the open board K40 controllers for the budget machines. Now it's just a matter of sourcing from a decent US vendor and getting the machine on it's way to me and organize our office and get a vent installed while it's in transit. Appreciate the info

[Labmaster]

I have this machine as well and after a couple of modifications it is a nice unit now.

On my setup the laser is a couple of meter away from the pc so i am quite happy to have the ethernet option.
For safety reason i always leave the laserpower switch ( its a own switch for the tube powersupply) off, until the job is ready to go.

You should make sure that you get the laser with a RuiDa RDC6442 Controller, as this one has ethernet, can drive up to 4 axis, has a color graphic user display, the option to control relais (blower ..) and works with a quite stable piece of software called rdworks V8

A stepper controlled z table as i have upgraded works great.
With this i zero the table ( with a limit switch installed at the upper position ) to have the table surface exactly at the focus point of the nozzle.
In the software i then be able to set the material thickness for each single layer that i use. I never have to adjust the focus manually. ( Pen Up / Down Option in Layers Advanced Settings)
With this it is even possible to work automaticly on diffferent focus points within one job executed.


This controller with rdworks offers a couple of different options for getting processing data to the machine.
1. store a job onto a usb stick, copy the job from the usb stick localy connected to the controller memory, load and start from the control panel
2. transfer a job over usb cable or ethernet to the controller memory, choose, load an start it from the control panel
3. transfer and directly start a job over usb cable or ethernet from the pc running rdworks.

Instead of the full version of rdworks, stripped down versions could be installed as plugin for different software packages like coreldraw ...

Here is a thread where i posted some details about the mods i have done:
http://www.cnczone.com/forums/genera...tor-setup.html

best regards,
Walter

[RHBlakeman]

Thanks much for the info Walter, greatly appreciated

[Storen]

These are the upgrades I did on mine so far:
- Replaced the default bed-plate with honeycomb
- Attached a nice stainless square ruler for aligning precisely the origin point on the sheet material
- Added milliammeter
- Added digital thermometer measuring the temperature of the water exiting the tube.
- WiFi so I can control it remotely
- Added monitoring camera that runs over the WiFi
- Got a 1.5” lens focusing the beam better
- Got an additional HD laser head that supports 1” lens for super fine cutting/engraving

Other improvements:
- Reassembled and tightened the vertical screws for Z action. Now the work-bed is super sturdy and it won't shake.
- Leveled precisely all 4 corners of the work bead so now it is perfectly parallel to the head movement.
- Tuned all the mirrors
- Calculated the X-Y square angle deviation. I am using Skew in RDWorks to compensate the error and recalculated the motor step size for the tilt angle. Finally I can get perfect angles and dimensions.
- Reduced the idle-speed so the machine shakes and vibrates less.

Open issues:
- To minimize the amount of carbon build on the edges when cutting paper the machine have to run with speed 80-100mm/s or even higher. I haven't found a way to reduce the pronounced ridging (saw-teeth) effect on the cut edges at these speeds. Any suggestions would be highly appreciated!

Potential upgrades I am interested in:
- CCD camera positioning system. I know RuiDa (the company that makes the motion controller and the software) offers these “Laser Vision” systems. I have no idea what would require and how difficult the upgrade would be.

[Labmaster]

...

Open issues:
- To minimize the amount of carbon build on the edges when cutting paper the machine have to run with speed 80-100mm/s or even higher. I haven't found a way to reduce the pronounced ridging (saw-teeth) effect on the cut edges at these speeds. Any suggestions would be highly appreciated!

I would say this is the matter of a combination of different things:
The Linear Bearing system does not run smooth enough, the belts are not strong enough and the head mount is not stiff enough.
The whole system will then sometimes start to oscillate
I already made a stiffer head mount, what helped a bit.
I now hope that if the Linear Bearing system is fixed, the belts are even getting out of the game as then there might be no initial swing exciter anymore.

Potential upgrades I am interested in:
- CCD camera positioning system. I know RuiDa (the company that makes the motion controller and the software) offers these “Laser Vision” systems. I have no idea what would require and how difficult the upgrade would be.

I even already checked such feature and this is what i found out so far.

Buy a laser Controller that has the Vision Option integrated, mount a camera next to the laserhead (i guess a industrial USB cam version (adjustable optics) )
Then do some adjustments for having the offset of camera and laser be calibrated correctly.

On a easy machine without other fancy stuff, like movable z heads ... i think that the main part that is different between a RDC6442 and the Vision Controller system is mainly the PC software.
Unfortunately it seems that the Controller Hardware itself is used as a kind of Dongle, the Vision enabled software does not run on a cheaper controller. (not tried it myself, but this is what some told to me)


Best regards,
Walter

[Storen]

Hi Walter,

Thanks again for advising me on that. After reading your post I decided to check everything one by one as per your suggestions.

- Belts are not strong enough - my system runs relatively smooth. There is not much stress on the belts. Maybe they won’t last as long as the good quality ones but for now they do the job.
- Mount is not stiff enough - actually the head-mount of my machine is as tight and stable as it could be. No problem there.
- The Linear Bearing system does not run smooth enough - yes, cheap stuff… They definitely contribute to the vibration.

While I was checking the belts and all I noticed something that maybe the main reason for the head vibration on my unit - the gear belts are not centered on the belt-spools on the X-actuation assembly. They look like they are trying to escape from the spool downwards. This makes the gear-features of the belt jumping over the guard-flanges of the spool which makes the whole system shake. The reasons are:

- The horizontal square extrusion tube is not high enough to provide safe distance (2-3mm) between the rail and the belt path. Therefore the belt s touching the rail.
- The motor (gear-shaft) on the left side is mounted (per design) lower than the spool on the right and it is pulling the belt downwards.

Overall terrible engineering. It is such a simple assembly and there are so many mistakes. Probably a first-year student would have done it better… Sadly unless I redesign and replace half of the parts I wont be able to fix it…

As for the camera system - our controller RDC6442G is listed as supporting “Machine Vision” technology on the Ruida website. The RDVision software is also available for free download.
I couldn’t find any information on how to connect a USB camera to the controller tho. I suspect it may require a special piece of hardware installed between the camera and the controller. Also I don’t know if I can connect any industrial USB camera or it would support only the specific models sold by Ruida.

[Labmaster]

I think a Camera is not needed to be connected to the controller, i think it has to be connected to the computer where the vision software is running.
All the math (picture processing) is done on the computer side, not at the controller.
Maybe a simple usb cam would work.
The only thing why i mentiond a industrial camera is the kind of optic that is used on such specialiced industrial versions where the optical distance and field of view and the focus could be adjusted to match certain requirements.

A first test would be to install the vision software and then try to access the controller with it.
If this works the next step would be to hook up a generic USB camera and check if there is a way to get picture of it showing up in the vision software.
If this would work too, then i guess the biggest problems are solved as the only thing to do would be to mount the camera then next to the laser head and try to adjust the distance for it.

best regards,
Walter

[Storen]

//A first test would be to install the vision software and then try to access the controller with it.//

Couldn't connect. Tried both - network and USB. I sent a message to Ruida, lets see if they are going to respond.

[Labmaster]

This is what i meant with "a kind of Dongle", why should they offer such a function for free. I think they locked the special software versions onto special controllers (even if the controllers might be only different by lets say, a serial number)

I never got back any answer from ruida.

best regards,
Walter

[Storen]

Yea, It was too good to be true but no harm in trying.
The prices I found online for the whole set (controller, camera, software) were around $2500. As far I can tell they are using normal controller, average camera and basic, outdated software. The price looks quite ambitious to me but maybe there isn’t much competition.

I wonder if there is other brand or other way to make this upgrade.

Initially I wasn't trilled about the upcoming Glowforge machines, but now I think this “precious” feature and their competitive prices could make them very popular.

[Storen]

I also didn’t get any response form Ruida. Not even from their sales people at Alibaba.
Instead I contacted a couple of companies selling their CCD system and ask them to confirm with Ruida (in proper Chinese) if RDC6442G is compatible or not.
Today I received emails from both - As you suspected, its not compatible. I have to buy the whole package including the new controller.
The lowest price I got so far is $830 for RDV6442G and 3MP monochrome camera. Here are some pictures:

[nzhuhu]

Hello all, i do not know if this question been ask before or not. I have this Chinese machine, and i have Fiber Cable + Laser Welding Gun but I do not know if it possible to connect the cable to the Laser Tube or where to turn Laser Engraving Machine into Laser Welding Machine? Please show me some picture and explain because English is my second Language which I will not able to understand correctly even using Dictionery. Once again thank you and Have a good day to everyone.