I donāt blame you Grant, after the troubles with the last oneā¦since you havenāt extended the wires, how are you running the projects with the LM? Taped everything to the z axis?
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@stevendq I have a bracket that supports my dust collection hose so that it doesnāt pull on the dust shoe. I can sit the driver on that bracket. I just put a screw through the board that the driver is attached to and screw it to the bracket. At some point, Iāll get up the courage to cut the wires on the laser and solder on the 4-connector molex plug. (The 4-connector cable is still in the drag chain.)
Then Iāll be able to mount the driver board back where I originally had it. I must say, though, that it is really convenient to be able to push the āweakā button on the driver board when it is right in front of me on bracket.
Iāve started running the dust collector with the hose just pushed through the bracket to suck the smoke away. It works a treat.
@stevendq, @gwilki, Iām assuming that the wires you are talking about extending are between the driver board and the laser assembly. Make sure you use a heavy gauge wire of at least 14 gauge. This will probably be heavier than the current wire, but thatās ok. You want to minimize voltage drop across the longer wire. More voltage drop equals less laser power. I used 12 gauge wire with a super flexible silicon insulation. I bought 10 feet thinking Iād have a lot left over, but I used most of it, routing it through both drag chains. I put connectors at both ends of the wire/cable so I could remove both the laser and the control box/driver.
@paullarson Tks, Paul. I have a 4-14 in the drag chain now. I may well look for a good 12.
What did you use for connectors?
I used these:
https://www.amazon.com/gp/product/B01JQ2X4BE/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1
This is the wire I used:
My set up is probably different than yours. I have a laser control box that I have sitting on top the LM control box, mainly because the PWM wires that go between the LM control box and the laser control box are short. Power also feeds into the Laser control box. Out of the control box are two wires that provide power from the laser driver in the box to the laser. These are the wires I extended and used the above connectors on.
P.S. because my crimping skills are somewhat lacking and because I trust solder more, I crimped and soldered the wires into the connectors.
@gwilki that sounds interesting. I was thinking about mounting the board closer to the laser for the same reason.
@paullarsonā¦yes based on @gwilkiās experience with smaller gauge wire I was going to use 16 gauge, but I am reconsidering 12 - 14 gauge due to the distance of the run.
Now trying to figure out the best way to secure the laser control module since my PWM wire and connector are short as well. Right now its sitting on top of the LM control box.
@paullarson @stevendq Paul: My setup is like yours - or was. I may change it. My laser box was sitting on a shelf on my table, close to the Mill controller. I had an 18 gauge - 2 conductor wire running from the pwm plug on the Mill to the pwm jack on the laser box. Then, I had 4 conductors running through my drag chain from the laser box to the laser itself. Two conductors were for the fan on the laser and two for the laser. That 4 conductor cable was 18 gauge.
When it got the replacement laser, I just used the short cables on it to test things out. Now that all is looking good, I may go back to the first setup, but with thicker gauge wire for the laser. Iāll leave the 18 gauge in place for the fan, as it draws practically nothing. Right now, I have 4-pin molex connectors on the end of the 18gauge cable and I had the same on the defective laser. I got these connectors from an old computer power supply. They are pretty robust, so I may stay with them.
The other option that I am considering is simply to stay with my ātemporaryā current set up. Simply keep the short wires and use a longer wire for the pwm signal. The benefit to me is that the laser box is front and centre and I can see and use the āweakā button very easily. As I have a hose bracket that the laser box sits on, the only downside is that the installation isnāt as pretty.
I would think there may be some voltage drop in running the PWM wire that way too. So bigger gauge may be needed there. Not an electrician, just know enough to be dangerous.
@gwilki I like the idea of this setup and had already been thinking about a mount to the LM that would allow the laser and controller to be mounted on the Z axis to access the low power button. I would have to mount the control box somewhere anyway. I donāt think weight would be an issue on the z axis.
@stevendq Iām sure that you are right, Steve. Clearly, there is more drop using 18 than using something thicker. I just donāt know the implications of it. Since all āspeedā signals from the software would be affected by the same percentage drop, then, relative to one another, they are the same, regardless of the voltage. Given that the pwm signal sets the power of the laser, I suppose that I am losing some power. It just occurred to me that I have no idea what I am talking about. I may experiment replacing the 18 gauge with something thicker, using the same settings in Lightburn, the same file and the same wood just to see what the difference is.
Iāll report back with results.
It sounded good thoughā¦
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@gwilki, I donāt think you need to worry about losing any laser power by extending the PWM signal. Itās a very low current signal and laser power is determined by duty cycle of the PWM signal and not voltage level. I would think the 18 gauge would be just fine.
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Thanks for the help @paullarson
Just to let everyone know how I have mine set up. I currently have both the PWM signal from the Longmill controller as well as the 12V power to the laser going through 20 gauge wiring, without any ānoticedā issues āyetā. Also, my laser module has the driver board built into the laser module.
The reason for the 20 gauge wiring is because I had a suitable length of 20-8 conductor cable to run through my drag chains and it is still substantially bigger than the 22 or 24 gauge wiring that came with the laser module. This also leaves adequate conductors to power red laser line modules to give me a crosshair, if I ever get around to building it! 
If I do come across any issues I will upgrade to 18 gauge wire but so far, so good!
Dave
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Thanks @djgrant181 for the info. Looking forward to getting m oi ne settled some time next week.
@djgrant181, If there is an issue it would be loss of laser power. You could mitigate things by using some of your extra wires. Use 2 wires in parallel 12V and ground. The PWM should be fine as is.
@djgrant181 Tks, Dave. My unit is different from yours in that my driver board is separate from the laser module. I donāt know if that brings into the play any performance difference the wire gauge may cause. Just sayinā.
Alright guys. I need to make a decision. 1. Do I mount the laser and control unit next to the router mount and run long power and PWM cables? OR 2. Do I mount the laser on the router mount, the control unit next to the cnc control box and run long wires to the laser and fan? I need to get this done and not sure of the best way to do it. I keep flip-flopping in my mind. TIA.
@Heyward43 Pros and cons IMNSHO
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+Long cables for power and the PWM do not bring with them any wire gauge considerations. + You are using wires that are already connecting the laser driver board to the laser module. - You need to come up with an easily removable mount for the laser driver board, assuming that you do not want the laser in place when you are using the router. - This may be a stretch, but I wonder if all the moving in x and y over time will affect the driver control board.
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+Long cables from the laser driver board can be fed into the drag chain, keeping things pretty. +Assuming that you put a plug on the end of those connectors and on the drive module, the driver board can be permanently mounted. + You can simply unplug the laser module from the long cable for removal when you are using the router. +The PWM cable can be very short. - You should consider wire gauge for the two conductors powering the laser. (With all due respect to David.)
Clearly, H, some of these overlap. They also donāt take into account any phobia you may have about cutting the wires that came with the unit - the 4 connectors powering the laser and the fan. I suspect that I am a club of one in that regard.
Either setup will work. I believe that I will come around to cutting the wires and using your number 2 setup. It is much cleaner and does away with the requirement to find somewhere to mount the laser driver board on the router mount. I have mine on my hose support now, but it is far from clean.
@gwilki Thanks for the reply Grant. After reading your info I may opt for option 2 also. Like you I donāt want to leave all that weight on the Z albeit itās not a lot. And as you say possible vibration issues to the controller and/or laser. Another thought on that vein is dust buildup in the both pieces. I like the idea of being able to remove the laser and put it in a drawer when not in use.
As for wiring I have 2 pieces of 14 gauge wire about 15 feet long and 5 rolls of 18 gauge wire about 25 feet each roll. I figured using the 14 gauge on the laser and the 18 gauge for the fan. Would that work to minimize voltage loss? Or do you think I can just use 18 gauge for it all? As for cutting the wires I thought I would hook it up and test it freehand for a couple of minutes to make sure I donāt have the problems you had since I bought the same one you did. And since Iāll have the controller right next to the cnc controller for testing I wonāt have to extend the PWM very far and that wire belongs to me.
By the way, I have tried playing around with LaserWeb and LaserGRBL. So far Iām not feeling comfy and cozy with either one. I downloaded the LightBurn trial last night and have been playing around with it and watching a ton of videos. Itās a lot more involved but so far Iām managing to understand what is being presented. Iāll probably end up getting a license. I also tried the JTech post processor for VCarve but I couldnāt get it to work so gave up. LightBurn was a lot easier.
One last thing. I couldnāt find a 2 pin plug for the PWM (all my fans had 3 or 4 wires) so I ordered 5 (not sure why 5) of the plugs with 4 inch wires. Unfortunately I didnāt see the statement that it was a 5 pack. Soooo, I ended up with 25 connectors. If you know of anyone needing one let me know. Each one ended up being about .20 cents apiece. If anyone needing one can send me a stamped self addressed envelope and Iāll give them one.
Thanks again for the help.
@Heyward43 I agree that your option 2 is the preferred way to go. For me, dust is not an issue with option 1, as I remove the driver board from the Mill when I am not using the laser. That is what I am doing now (temporarily, I now believe). I remove the laser module and the driver board, keeping them wired together. I donāt think plugging and unplugging those small white connectors on the driver board is a good idea, for me, at least.
Edit: One advantage of option 1 that I omitted in my last post is the easy access to the fire button on the laser board. With the board on the my hose guide on the router mount, I can easily get to the very small fire button. With the board mounted close to my Mill controller, it is all but inaccessible. LB has a software fire button, but when using VCP and the Jtech post, that is not open to me.
On the subject of wire gauge, I think the juryās still out. David is using 20 gauge and all is well. Andy used something quite fine, also, as I recall from his video and write up. In my failed attempt, I used 18 gauge, but the failure was owing to a bad laser, not the wire. I looked at some electrical info sites. There is no question that the voltage drop over 18 gauge wire is greater by quite a bit compared to thicker wire. I guess that itās just a question of how that affects what we are trying to do. I am only using my laser for etching, not cutting. I have the router and the drag knife for cutting. I seldom use 100% power, so a drop in power caused by 18 gauge wire is likely not an issue for my projects. That said, I have some 14 gauge speaker wire kicking around and will likely use it for the long laser run. Iāll keep the 18 for the fan.
I have used both LightBurn and the Jtech posts successfully. I like the Jtech posts as I am fairly comfortable with the VCarve/UGS interface. The dragon that I posted in the projects thread was done using that process.
I bought the LightBurn licence yesterday. I had used the trial and they extended it for me when I wrote and told them about my laser issues. I did a couple more successful experiments with it and figured that their support deserved my $54 Cdn payment. I like the flexibility of the software, but that does add complexity compared to the simplicity of the jtech post. Keep in mind that LB was not developed for diode lasers. It was designed for CO2 lasers, so much of it is not applicable to our function. It took me a while to get onto the way they use to set 0. Itās not at all like in UGS. I think that Iāve finally got it. I wanted to make sure that I could use LB and UGS on the same project. Iāve done a couple of projects now where I burned a design in LB, then cut out the piece using UGS/VCarve. Iām slow, but getting the hang of it. 
The big plus for me with LB was the idea that I donāt need to convert images to vectors. I can simply import a .jpg, for example, and LB will burn it. VCarve/Jtech will not do that, or at least I was not successful. I think that PhotoVCarve would, but the Jtech posts will not work with it. (I tried.)
Long winded this morning, arenāt I?
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