Natalie's 2.x Build

[eilatan]

I have been working with CNC machines for a little over a year now. I am currently putting the finishing touches on a 3-axis 5x10 CNC router table with a vacuum table. I am working in the field of Architecture and a Laser cutter has been on the list of useful machines that will help to further my studies. Bart is awesome, the open source plans and support provided has been great.

I started my build a couple of weeks ago. I had a project that needed some acrylic laser cut and it was my goal to have the machine built in a week to be able to utilize it. I was very close, but my soldering skills are not great. I had my x and y motors working great, but my z motor was having problems so i removed it to fix the soldering. I ended up starting a fire and killing all 3 drivers. That was fun!

I ordered most of the major kits from Bart, with the exception of using CNColtech for the laser and laser PSU, and lightobject for the mirror kit.

Building the frame was a little frustrating because i kept forgetting to put in the correct amount of nuts and ended up disassembling and reassembling quite a bit. I followed the build document to complete the build, but i did it a little backwards because i got the mass of the machine and then began to work on the electronics. I cut all the plastic pieces myself using scraps that i had in my lab, and i also cut the skin using Alupanel. I did vary from the traditional Blue of the 2.x and went with Traffic Light Yellow. I have to say one of the frustrating parts of the build was fabricating the z axis lift pieces. I used cast acrylic for them and found that it wasnt very forgiving. The pieces are still on my machine at the moment, but i plan to use the laser to recut them as soon as i have it up and running. So once i had the frame together, the base skin on, vrails and gantry in place i went forward with the electronics. This has been my first time working with such complex electronics. I know that on the larger scale this is technically a simple project, but for me it was a challenge and a great learning experience.

I am using Mach3 to run my laser. I have a some experience with the program because that is what we are running our 5x10 CNC with. To the best of my knowledge i have wired everything correctly. I have double checked according to all the resources i have available and it seems right. I am using Bart's 3axis interface/PCB board. I am at the point now where my mirrors are almost aligned, i say almost because it is cutting at an which is obvious in the test material that i have and also when i attach the air assist nozzle the laser gets stuck in there. I have run a test cut and the gcode created works. I output the files from Cut2d using the buildlog post processor so it is telling the laser to turn on and off in my cut. I can see that in the code and my laser triggers when i hit the test fire button however i am stumped. i cannot get my board to communicate with the laser and no part of my interface panel works. I recently updated to Bart's xml file to see if maybe i had something set up wrong in mine but i get the same result. i have checked over the wiring of the board and tested the connections to make sure there is power going to it. I cant seem to find the problem. Im pretty sure it isnt the board because i sent it back to Bart for repairs on the drivers and I am confident he sent it back to me working. I checked to make sure all the loops were connected to possibly trigger the safety turn off that is integrated into the board. I have a water pump system running but on the board it is looped, it triggers on from the outlet i set up in back. I have tested my limit switches and they work within mach3 so there isnt an open loop there. One thing i did notice though is that if it is running a code(laser not outputtng) and i open or touch the limit switch for the opening, a green light on my Laser psu flickers. Basically i am having trouble having the machine communicate with the laser in order for it to output during a run or having any control of it from my interface panel. Any insight would be greatly appreciated and i will continue to update my buildlog with more details to help the next builder out.

[eilatan]

I shot a video of the first cut i did. Technically not a first cut because i was manually triggering the laser from the test button, but i was anxious to see what this thing can do!
http://youtu.be/sZuFcGkfnj0

[J45on]

Looks great in yellow
What do you have engraved on the front panel ?

[BenJackson]

I am at the point now where my mirrors are almost aligned, i say almost because it is cutting at an which is obvious in the test material that i have and also when i attach the air assist nozzle the laser gets stuck in there.

You can read about this in my buildlog (and probably others): Your final mirror (the 45 aimed down) is probably twisted. There is a collar on that to retain the lens, but the part above that *also* threads into the part of the assembly above the plate. If you loosen it there you can rotate that whole tube. Rotating that 45 degree mirror can swing the beam quite a bit from front to back.

Test by removing the final lens and ensuring that the final spot is directly below the lens assembly.

(It is also possible that your entire gantry is not level front to back, which you can fix by shimming the final mirror assembly or by trying to level the gantry itself)

Also that yellow looks really sharp!

[eilatan]

Ben,

Thanks for the input on the laser alignment. I did read your forum a couple days ago and i realized that was probably my issue. Thanks for the tips about the shims though, it may come in handy. I plan to make the adjustment soon, have just been busy trying to troubleshoot firing the laser from my panel.

I am really happy with the yellow Alupanel. its a great material and the color is awesome. I milled makeLab into the front, its the name of the lab where i work and where my machine is housed.

[bdring]

Skins: The skins look great. Nice job. HDPE is a lot more forgiving on the parts. You can press in stuff easier because it stretches. With acrylic, you might need to oversize the holes. On new pieces, I usually test fit the bearings before the final cutout pass, so I can adjust the holes as required.

T-Nuts: That is frustrating. I removed the section from the build instructions. I put the whole thing on the frame drawing now. It also lists the full count and not just the extra nuts. I found that to be better. I recently built a frame and still forgot some nuts even though they were clearly listed. It is easy to get excited and move ahead too quickly.

Laser Interface Panel: You talk about test firing the laser, but say the interface panel does not work. Did you bypass the interface panel?

The system is fairly simple. You have a safety loop that connects the water pin on the laser power supply to ground. It loops through several switches. Opening any switch opens the loops and prevent firing the laser. Use a meter to check that ground water pin does connect to ground when all switches are in the run position. You can do that right at the laser PS terminal block. Many people wire the cover switch wrong. It wires differently than the limit switches. Measure continuity across each switch.

There is a simple circuit shown here.
http://www.buildlog.net/wiki/doku.php?i ... wer_supply

You can use this to test the laser and slowly replace the wiring shown with the wiring in your machine. There are three basic items: Test button, water connection and pot. Replace one part at a time.

[eilatan]

The frame drawing looks great.

When i said bypassing the interface panel i meant that i have tested the connections to it and there is power running through the lines, but i am not getting a reaction from any of the components on there. The red test button on the laser psu is what i have been using to fire my laser. I did go through and rewire like the diagram you posted. i had a switch connecting the Level High to the 5VDC. I got no reaction from my laser or the test button on the psu. I wired the ethernet cable back into the supply following the correct diagram, powered on, and still wasnt triggering from the interface panel but the red test button on the psu fires it. I double checked my water supply loop on the board too. I think my cover switch is wired correctly, it triggers when running in mach3. Also when i start up mach 3 it toggles the switches if they are preventing the continuity. when i open the cover the green WP light on the laser psu lights up. so back to where i was..

[bdring]

I don't have a test button or light on my laser PS so I cannot comment on how that works.

Mach3 should not know anything about the cover interlock switch. That is a clue. Measure (or beep) the resistance from the WP pin to ground on the laser PS connector with all your wiring in place.

I do not understand this statement

when i start up mach 3 it toggles the switches if they are preventing the continuity

Is this in reference to the dialog box that pops up when you try to reset with limit switches preventing it?

[StigOE]

Many people wire the cover switch wrong. It wires differently than the limit switches. Measure continuity across each switch.

Is the correct way to wire the cover switch so there is continuity when the cover is closed? And the limit switches should be wired so that there is continuity when the switches have not been pressed? If this is the case, in my view, your schematic is wrong because you have used NC switches for all three switches instead of just for the limit switches, so no wonder a lot of people have the cover switch wired wrong...

Stig

[bdring]

These are 3 terminal SPDT switches. The term normal and closed confuses people because the run mode of the laser has the cover "pushed" and the limits not "pushed". There is no common "normal" for all switches. All switches complete the circuit in run mode and open the circuit during a fault, so breaks in wiring tend to cause a fault. The schematic show all switches in the run position.

This is the proper way to wire something like this The user guide is pretty clear on this. The people who have wired the cover wrong, usually did so because they wired all the switches the same way without thinking.