My New MPCNC

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41

Ah, I think you want to jumper across the positive and ground from the 5A side to the 12A side. D9 gets powered by the 12A side.

1 Like
42

Ah

ok, will give that a shot tomorrow evening and get back to you.

thanks Jeffeb3

43

Hi Jeffeb3

Bridging the 5A and the 12A made no difference, still have the issue of the laser not varying with the graduation of the greyscale in the picture.

I did try changing the Fan pin from 9 to 44 again as per Leo’s instructions but that made no difference apart from barely running the laser.

44

If you send it the manual commands show in the instructions does the power vary then? As in is this a hardware or software issue.

45

Hi Ryan

OK some more testing on my laser today.

I can confirm:

M106 S0 - Laser Off
M106 S255 - Laser On
M106 S125 - Laser Half Power

I tested variations in between those numbers and it visibly effects laser strength, but I also used a piece of card and managed to go from no impact, to light burn, heavy burn to burn through the card, so the M Codes are defiantly effecting the laser strength manually, just cant understand why its not when trying to engrave a picture, the LCD shows the fan value changing to the different strengths as its etching the picture but just doesn’t seem to be having an effect on the laser. I am stumped!!

 

 

46

Dang it I have replied 3 times…

Condensed version.

Ty putting the “f” commands at the end of a G0 or G1 line. The gcode looks funky but that is the only 100% wrong thing I see.

I only use my laser for vector stuff lately, maybe I will try it tonight and see if your code works. If I take a break from the current project I’ll give it a shot.

47

Did you post the gcode somewhere?

You should also make sure there aren’t any S256’s or S254.5 or something. I wouldn’t trust Marlin to parse it right.

Did you try with a simpler image? Something like a black circle in a gray box or something? Might help you narrow it down. I could even be 1/2"x1/2" (try your favorite flag, that would be neat seeing it that small, but I digress).

48

Hi Jeffeb3

the gcode is posted in the post with the pic of the leapord, it’s called leapord.nc

49

There was just a post in the laser thread. The new firmware is choking of the parenthesis and that “F” command need to follow an “G” command.

Try the following.

 

50

Hi Ryan

Thanks for the reply, unfortunately that made no difference at all, I had already been manually putting the Feed Rate in besides the G commands as per a post of yours in someone’s laser post.

I contacted the manufacturer of my laser and they seem to think that the D9 terminal on my ramps board, the voltage control is on the negative and not the positive, I thought it may be an issue with the ramps board so I put a new one on, same thing. The laser works great for cutting, just doesn’t seem to work with greyscale engraving.

I have been given a small circuit to create to try to put between the Ramps and the laser but have no PNP Transistors so waiting for them to come tomorrow. Will see if this makes a difference.

My Dremel bits should be here tomorrow aswell so will get a play with them.

51

That doesn’t make sense to me, if you can manually lower the power, I would assume that means it works?

52

Hi Ryan

it doesn’t make sense to me either, but it could be that my testing is at fault and the laser is only turning on and off at certain values, at the end of the day it’s the cutting that is more important but would be nice to do grayscale engraving.

53

Tell me what happens with this one.

lasertest.gcode (386 Bytes)

54

Thanks Ryan

will give this a test tomorrow, managed to track down schematics for the laser driver, mines is the Mk3 not sure if these will tell you anything or not.

http://www.robots-everywhere.com/re_wiki/pub/web/Main.LCheapoSchems.html

55

Hi Ryan

I tested your Gcode, I get 3 black lines then the lines begin to degrade (no change in greyscale, but broken lines) until not visible.

56

You might want to show that to the laser manufacturer I think something else is wrong. That code is as simple as it gets and slow so it should work. I would guess your driver is funky. Or maybe they can reply with a test code that they feel should work?

57

I also tested the circuit that the manufacturer wanted me to try, that didn’t work either, so my next question to them is my driver faulty, waiting on a reply.

58

That might actually make sense. Because D9 is designed to run a large load, the signal might not be switching fast enough with a high impedance load (basically no load).

Or, it could be that the differential between D9+ and D9- is switching between 0-12V, but the +terminal is always 12V, but the D9- is switching between floating and gnd. If they are really looking for the difference between D9+ and some other ground, then the floating ground pin wouldn’t turn off the laser.

59

This might be why Leo switched pins, and why the voltage divider didn’t work. I know there was an issue and it might have been speed related. I can’t remeber the conversation. I will check and see if I still have it in my PM’s.

60

Hi Jeffeb3

Yeah that’s exactly what they said and that’s why they gave me a circuit to build, although I have no idea how its meant to work, but I did build the circuit but it didn’t work.

I have attached the circuit if you want to have a look, you will be better placed as to see what it is doing.

[attachment file=44620]

LaserCircuit.png
LaserCircuit.png962×655 8.45 KB