Attempting to upgrade machine from 40w. Help with wiring please

Hi everyone. Been using a k40 for about half a year and its not strong enough for what i need so trying to upgrade. So heres what Im working with.
Old is MYJG 40w. Diagram can be found here. https://www.amazon.de/Cloudray-Laser-Supply-Engraver-Cutter/dp/B079MHKQXF?th=1

Board is a Cohesion 3D Laserboard.

New is a HYDY13 Cloudray. Diagram can be found here Cloudray 100W 110/220V HY-DY Series DY13 Power Supply For RECI W2/W4 – Cloudray Laser

The new power supply has a white cable in back that the old one did not. Im guessing this is a ground? Cloudray didnt send any instructions or diagram in the package.

Heres what i think so far. On my current one i have k+ and L which connects to switch laser control high and low on new board but Im not sure what goes where.

G on original to the Input control signla 0-5v on new one

IN, and 5V will connect to the blue wire on original and all to the output power 5V.

On the left side the ac/ac/ L N is pretty easy but the far left on new shows FG in letters and diagram shows ground on the new one. One the old one theres two different sets of wires on left showing FG and signal to neg so not sure exactly what goes to what there. If its the yellow and black together or yellow stays and black is somewhere else.

I appreciate any help I can get. I bought the 40w not realizing it wouldnt fit the needs I had and need to upgrade to a stronger laser. I sent the info and photos to cloudray which said it would be fine to upgrade the machine. Thank you.

Theres a big size difference so about to tear the side of the machine apart and cut the metal to make this power supply fit easier.

My plans for the laser extension tube is up in the air right now. But time to frankenstein this machine a bit. It wont look pretty but hopefully will work.

Can I ask what happened to make the stock K40 parts “not strong enough” and what was your air assist configuration( front to back please )?

Im shooting thru 6-8mm clear acrylic. Colored is fine but not clear. Takes way to long and too many passes at times for things. Other materials the same. Im doing double passes to get things done how I need them. Air assist is fine. Some items burning until I added a different fan and much better. I had help setting the bed height for proper adjustment. I need to cut with a single pass tho not double. And wood doesnt cut easily without burning. Someone else my wife knows uses and 80w for same thing with zero issues and much faster.

I have a diagram somewhere for this conversion but I am not home.
Will respond tonight or tomorrow unless someone does before me.

Please post a picture of the control panel you plan to use.

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If you are using a “fan” for air assist then that is not an appropriate setup for a CO2 laser air assist.

I’m asking because if you do not have your machine setup correctly and don’t have certain things added to your K40 then there’s a good chance even a new tube and power supply will not work for you after a while.

Things like a proper air-assist, tube current monitor/meter, water temperature monitoring and possibly cooling, knowing exactly what your focal length is and how to accurately set and measure it to name just a few.

A stock K40 setup correctly could cut 6-8mm acrylic in one or 2 passes. An upgraded full 40W tube would do better. 100W would likely be just way too long a tube to safely operate in stock K40 and so a much larger K50/60 would be a better fit.

What are you powering the Cohesion board with?
What do you have connected to the 5V on the current LPS?

Thanks. I understand and it took almost a week to get setup originally because of this and had several people helping. But 2 passes is too long and longer it burns on clear the worse it looks. What I did find was the type of plastic made a difference and clear was harder then cutting solids. The “proper air assist” is still there but just wasnt working as well all the time and the exhaust was horrible regardless of the config until I made other changes.The people my wife knows do the exact same work and said the 40 wasnt good enough and after 6 months I agree. Thats the reason for the upgrade. I will possibly rebuild the whole unit at a later time.

The cohesion is powered independently to a plug. The 5v white wires setup are going to the controls here.

Thank you for your help

Please tell us you have a mA meter on there and you never exceeded 18mA.

Just to let you know, there are some K40 geeks here and not just people who have a K40 but people who have spent hours testing single features, repairing laser power supplies, etc. I understand you might think you have the proper configuration and ran your machine properly but it is so common people do not we MUST ask and insist on a complete understanding of what you have and how you’ve operated it. “proper air assist” tells us nothing.

And if you haven’t noticed, the laser tube power capability is directly proportional to its length. So have you even looked at the length of a 100W tube compared to the ~35W tube the machine comes with? You are talking about 700mm vs 1450mm… at 50W or 60W might do the trick but you really need to dump the digital power control display. Soooo many laser tubes have been ruined by using only that control.

Hey. I ended up with a 40w because people said it would work. And yes I am able to cut things. But whats acceptable to one person as “working” is not acceptable to another. 2 passes at a slow speed for me is not acceptable. The lightburn software forum is where they helped me originally and some on reddit. Why do I need to go thru the history of everything Ive done when everyone that does the SAME work all use a higher laser power? Even people my wife knows personally that have been doing this for years? Im not interested in barely making it work and moving up from a 40w to a 50w in the “hopes” that it solves the issue. When others that the use case is exactly the same as mine use 80 and a few people in Australia are showing their machines with 100w lasers? Their videos are speeding thru the process yet mine can not. You really think its a benefit for me to spend hours and move from a 40w to a 50w? Ive made the mistake of going with what can barely work.

Obviously theres people here with waaayyy more knowledge then I have about machines or I wouldnt be here needing help. But what I need now isnt trouble shooting. I need to get the new laser working (its been sitting in the other room for a month now) and making sure I dont mess it up in the process. The original plan was to build a new machine using Further Fabrications setup which i purchased the plans. But because of the Ukraine war going on we’ve had to help many friends there and their families which takes a toll financially so the build will have to wait until later. I still have people we are trying to help wives and children relocate. In the meantime I need to get the new laser working with what I have and limit other large expenses. The laser power supply and several other items have already been purchased. When things settle down a little better I will start going back to the original plans and moving the laser over to the other machine.

Please take it easy. Folks here want to help.

The reason you are getting questions about how you are doing air assist is that if you are doing it with any sort of a fan, 100W isn’t going to solve your problem. You wouldn’t be the first. Lots of folks have thought that a fan to move smoke away from the nozzle solves the problem, and haven’t realized that you need air through the nozzle using an air compressor or diaphragm pump or similar to get good results. You may well be doing that already; just say so! :relaxed:

The reason for the questions is to help you make sure that having gotten the help you are asking for, you get the results you are looking for.

Please don’t take offense.

Please help folks here help you.

I apologize. Im only trying to explain everything because every time i ask a something on any forum everyone wants to trouble shoot and Ive been thru this before lol. Several times. If a 50w or 60w works for others then great. I have a 80w sitting on my table in the work room already and other items ordered. Of course i know the larger the laser the larger the tube. In the photos you can see where the tube extension goes I just didnt buy it with the machine and now unfortunately cant get a hold of it.

I do have a regular air assist with compressor in the rear and nozzle comes out right at the tip. There are upgrades to the machine and bed is larger then a standard k40 size. I use the fan on some cuts because the laser needs to move so slow right now with a 40w to get the 2 passes to work all the time it burns the plastic and leaves a burn mark on the sides. It doesnt happen when i use the fan at the side and same result i get except its cleaner with no burn marks. I went thru probably a hundred cuts trying this out and got that tip from Reddit I believe.Depending on material and cut needed I use the fan or i dont.

When I get the new laser working I’m pretty sure I wont need the fan at all and regular air assist will be fine.

For now I just really need to figure out the swap and wiring without making errors and dont want to blow this new laser. The rest I can deal with after on the machine.

Attached is a preliminary from-to diagram.
This is NOT a schematic or wiring diagram, it intends to tell you how to move a connection from the old LPS to the new one.

Please thoroughly review the diagrams and then answer the questions below.

There are still some open items before this is complete. I will reference the diagram using the circled numbers.

#1 & 2: where are the current wires on the current LPS connected to? These are the Yel, Blue, and Black wires on the rightmost connector.

#3 exactly where on the C3D board is this wire connected. How is that output configured in the smoothie configuration? Attach config file.

#4 this is not a from-to wire. This wire must be added and this is where you would wire in your interlocks… which you need for safety!

#5 This connection may be a challenge. The digital panel provides a ground on the K+ connection when the Test Switch is pushed.
If we wire the L signal to the new supplies TL then the only fire pin that is left is the TH pin which requires a high (5V) to fire. In other words, the K+ is not the right level to connect to TH.

The K+ wiring options are:
a. invert the old K+ signal and connect to TH [that’s ugly].
b. connect the old K+ and the L signal to the TL pin. If the L signal is connected to an open drain MOSFET on the C3D then connecting L and K+ (wire OR) both to TL should work. See the simplified drawing below.

I have never wired a machine this way so I do not know if there is something at the TL input or K+, L outputs that would create a problem. For instance, when L and K+ are not asserted will the TL input pull up the signal or will it float [does that matter to the LPS]. Or is there some condition that I do not see where L and K+ will interact?
To test when implementing this schema we can first connect K+ and verify that the TL pin will pull up properly and then connect the L pin.
c. convert to an analog panel. An analog panel provides better visibility & control of the machine’s power when a ma meter is included. In this schema, we can wire the discrete switches in a way that we can use TH.


From-to diagram


Simplified fire circuit

The reasons I was going down that path of understanding how you got here is:

  1. many many K40 users over drive the cheap tube by using the digital display and not knowing they are over driving since they have no Amp meter installed. So tube wear is accelerated and performance is greatly reduced.

  2. the stock laser tube on a K40 is not a 40W tube and even driving it properly you’re only getting maybe 35W out of it.

  3. air assist design is a big factor in how well the “cutting” happens. People will use a cone nozzle with a 4-5mm hole and it’s 30-40mm from the work surface with a weak aquarium pump. Looks good, seems right but it is not a very good air assist. air assist should be low volumn, closely focused, high speed air directed at the cutting focal point.

  4. Putting a 1400mm tube in a machine which is just over 700mm wide is not really a good idea so it might be a better solution to get a bigger machine which already comes with a more powerful tube and can safely hold the tube and protect the tube and protect the operator from high voltage.

  5. Having a friend help you with focusing the machine seems odd since they only thing you need to do is a Ramp Test and measure your focal length then adjust your bed or work material so either the surface of the material is at the focal point for thin material or adjust so the focal point is in the center of the material.

It really shouldn’t take hours to answer a few questions but since you really don’t want to answer these questions, I’ll let others assist you in your upgrade as you defined needing since you already have the upgrade parts purchased. I must have missed that in your previous discussions.