Cheap diode laser upgrade


(Gary Webb) #1

So I’ve purchased my first laser machine. A cheap diode laser off of ebay. (link below and pics attached)
My issue is with the knock off nano arduino running grbl .8. I’ve struggled for days to get it updated with no headway made. This pushed me into the decision to purchase a proper controller, the cohesion board. I do have a lot of questions before I do this.

My current board, has ports for my stepper motors, the laser itself, power etc… will the cohesion board have the same ports? Will it work with a diode laser? Does it have the ability to connected the lightburn cameras?

HEre is the link to what I’ve purchased.

Ideally, I’d like to reuse whatever I can, and if I cant reuse something, I’d like to know ahead of time so I can purchase everything I need.


#2

Thank you for providing the picture of your controller.

Can you confirm where each of the wires goes? I think:

  • The 2 pin red and black are for the diode?
  • 2 Y motor cables?
  • X motor cable?

Can you show pictures of the diode module itself, and advise of any specs, labeling, or markings written on it? If there is a sticker on the front of it as I can barely see in the ebay listing, please sent a picture of that.

The C3D LaserBoard has provisions for driving a laser diode. However we do not have an easy way to connect 2Y motors to the single Y port. If you can wait approximately 2 weeks, I can have manufactured a breakout board to act as a splitter.

That 2 pin connector for the laser itself is a screw terminal on the C3D, so you’d need to cut or adapt that one. Pretty simple.

Yes, the LightBurn Camera plugs into your computer and is not controller dependent. You can purchase the Official LightBurn Camera from us as part of your order if you do not have one already.

I also have some concerns about the power brick that comes with the machine, but that’s a fairly lengthy tangent to get into. Please do reply back to continue the conversation about the points I have already mentioned, and do not place any order until we have figured out all the details and are in agreement about how to proceed.


(Gary Webb) #3

Correct, the two pin connector is the diode. Two Y controls and 1 X control.


(Gary Webb) #4

hmm sorry the pic is upside down. I rotated on my phone but seems to have flipped back over when i uploaded it.


(Gary Webb) #5

Also Im quite comfortable soldering, etc… I dont mind making my own break out cable for the two Y cables… Should be a fairly simple cut/splice job. My main concern is keeping everything tidy and clean.


(Gary Webb) #6

Ive attached two pictures of the machine itself.


(Gary Webb) #7


#8

Ok, great!

Here’s the short “how to do this” with the long “why it has to be this way” skipped in the interest of time (and difficulties with turning my brain waves into concepts decipherable by other humans :slight_smile:)

The LaserBoard comes with a 24v 4a Power Brick included. It needs a sufficient and clean power source to power it and the power brick that came with your laser will not cut it (but we will use it to power the diode, see onward).

I have made this mockup:

In this pic, the LaserBoard has its own power brick plugged into the DC Jack on the right side of it.
On the left side of the board, an adapter is used to convert the 12v DC from your existing laser power brick.

  • That 2 pin red and black wire from the diode, the red wire will go to the + marked here (reddish wire in pic)
  • The black wire from your diode will go to the Laser Diode Out - on LaserBoard (blue wire in pic)
  • A common ground must be established so the - from the 12v brick goes to the ground rail on LaserBoard (orange wire in pic).

I will include that adapter and some wire for you.

Here’s what you need:

  • LaserBoard, the 24v power brick is included with it.

  • USB Cable option, as the cable types are different and a high quality one like ours is needed for stable operation

  • Endstop switches, at least 2 for X and Y, I recommend this type: https://cohesion3d.com/shop/peripherals/mechanical-limit-switch/

  • The Official LightBurn Camera if you want it. You will probably need to make an arm and a mount to have it sufficiently above the bed and looking down.

You will need to wire it up (X motor, make splitter for Y Motors), add the endstops (the ones I linked will plug right in to LaserBoard’s endstop header row), and make some changes to the config file on the board’s memory card to set the bed size, homing corner, steps per mm and speed/ acceleration values for the particular machine, and the motor currents.

It’s all pretty straightforward in my mind, but as always I do encourage a tinkering and problem solving mentality to handle the unexpected surprises that come up :slight_smile:

I would ask that you take pics and notes along the way so that we can turn this into a guide, and I will try to help out as best I can.

I do caution that I will be traveling for a trade show starting next week. If you order in the next day or so I can get it shipped out before I leave, but my availability to answer questions will be a bit limited during my travels.


(Gary Webb) #9

order placed! Last question for now, if i decide to upgrade to a more powerful laser in the future, will this controller still be a viable solution, provided that the new laser is equal or less than the current voltage requirement?


#10

Looks good.

Yeah, if you get a CO2 laser in your future you can use this board for that. Look up the K40 and look around our forum at some of the larger lasers people are working with, the same board works with all of that.


(Gary Webb) #11

Was I suppose to order a total of 4 end stop switches? or just two? I just realized I may have misinterpreted your message.


#12

2 is sufficient to home which is what we really need here, you’re fine.


#13

The subtext was that if you get 4 you can also put a max one on the other end of each rail so you don’t overrun the ends, but it might be overkill.


#14

So just to be clear, I linked you the one type of switch, and you ordered the other kind we sell.

I’m sending you the kind I originally linked and had in mind.


(Gary Webb) #15

I noticed that Haha. I had the right ones the first time and then added the wrong ones to my cart the second time. Thanks!


(Gary Webb) #16

Ok so I have everything hooked up. Im having an issue with the Y motors though. When i try to manually move the, they grunt/grind, as though they are seized up or locked up. I’ll try and take a video. But for my dual Y motors, I essentially used the existing XH plug on the board, and then used a 4 pin header with 4 leads soldered to them to adapt to the screw terminals.

Pin out for my adapter

R1 - Pin 1
R2 - Pin 2
G1 - Pin 3
G2 - Pin 4

I built the adapter based off what I assumed was pin 1. Maybe motor 2 is flipped? I dunno… Unfortunately the designed of these motors made all the wires black, with no denotion as to which is which. I would -think- being DC, it wouldnt matter? So maybe I have something else wrong? What I -HAVE- tried is flipping my 4 pin connector to see if that would help, but the result is the same. I took a video and uploaded to my webserver, hopefully it will show up in the post. If not, here’s a link. As you can see in the video, the Y motors only seem to make a binding noise. The X motor moves just fine.


(Gary Webb) #17


(Gary Webb) #18

Ok upon further inspection, when I flip my home-made adapter, the gantry definitely moves a -little- but still sounds like its binding. Disconnecting the adapter completely, allows the gantry to move a little better, however, it still has a binding sound, and appears to be binding. I’ll take another video


(Gary Webb) #19

Normal position of adapter

Reversed position of adapter

Adapter unplugged

Adapter only


(Gary Webb) #20

The plot thickens? So I hit the reset button just for giggles, and during the startup, the Y and X motors move slowly and smoothly? But trying to move them manually in lightburn results in the above videos.