Hi again. I purchased a Monport a few weeks ago and I’ve been somewhat underwhelmed with it’s power compared to what I’m seeing others post about their K40s and what’s listed in the Monport manual. In the Lightburn version of the manual for my Monport 40W and it states that at 8% I should be seeing about 5mA . I have to set my Lightburn percentage to 35% to get to 5mA. I have the knob on the machine set to max power and the power reading is on the digital display on the machine.
I did a bit of research searching through the forums and I see folks mentioning their $31 is set to 1 whereas mine is set to 50. Can someone tell me what exactly this does and what would happen if I set mine that way instead of 50?
Here’s my $$ output I recorded along with the notes on the side that I had for my benefit. Thanks to you all for the help!
Grbl 1.1f ['$' for help]
$$
$0=10 Step pulse, microseconds
$1=25 Step idle delay, milliseconds
$2=0 Step port invert, mask
$3=6 Direction port invert, mask
$4=0 Step enable invert, boolean
$5=0 Limit pins invert, boolean
$6=0 Probe pin invert, boolean
$10=1 Status report, mask
$11=0.010 Junction deviation, mm
$12=0.002 Arc tolerance, mm
$13=0 Report inches, boolean
$20=1 Soft limits, boolean
$21=1 Hard limits, boolean
$22=1 Homing cycle, boolean
$23=7 Homing dir invert, mask
$24=800.000 Homing feed, mm/min
$25=3000.000 Homing seek, mm/min
$26=250 Homing debounce, milliseconds
$27=25.000 Homing pull-off, mm
$30=1000 Max spindle speed, RPM
$31=50 Min spindle speed, RPM
$32=1 Laser mode, boolean
$38=10
$100=160.000 X steps/mm
$101=160.000 Y steps/mm
$102=160.000 Z steps/mm
$110=8000.000 X Max rate, mm/min
$111=8000.000 Y Max rate, mm/min
$112=100.000 Z Max rate, mm/min
$120=500.000 X Acceleration, mm/sec^2
$121=500.000 Y Acceleration, mm/sec^2
$122=20.000 Z Acceleration, mm/sec^2
$130=300.000 X Max travel, mm
$131=200.000 Y Max travel, mm
$132=200.000 Z Max travel, mm
$30 should be equal to what is set in S-Value max, in Lightburn device settings, I believe.
$31 should be set to 1. These two values are used to compute the right value to tell your controller what pwm percentage you are using…
It being at 50, isn’t right, but shouldn’t cause what you are describing, I don’t think. Instead of the range being 1 to 1000 it’s now 50 to 1000 …
$10 has a suggested different value also…
You should always check out the documentation on setting this up for your specific machine. They’ve done the work to alleviate these headaches…
Is this new or used?
If you have these three things, it will work
properly working tube/lps
aligned and clean optics
focus
I’d suggest you start at m1 (mirror 1) and see where and how the output of the tube appears. The how is the resonance of the output beam defined as the TEM state, you want TEM0 state… anythign else is an issue.
But if you have a problem, you need to follow the beam to see where it has the anomaly.
I usually suggest this site, but it’s apparent down at this time… It explains some of the TEM patterns.
Then follow a good alignment procedure… Do you have one that you use as a guide (a link is good)?
Both are set to 1000. I thought the LB device settings were just pulled from GRBL settings?
Changed this value to 1
Does this have an impact on the power?
Thanks. Did not see Monport or K40 specifics here though.
Purchased new. I did a tape test on the laser head only and the pulse was dead center. I am pretty confident in my focus as my workpiece is flat and is adjusted using the included spacer. I’ve cleaned the mirrors and lens with rubbing alcohol.
I did notice that when I test fire with the laser set to max on the machine that I am getting 21mA but according to a chart in the manual I should be seeing 24mA for 80% and greater. Any idea what output I should be seeing?
Thanks for taking the time to post this detailed response. I certainly appreciate your help in troubleshooting.
What amperage output should I be seeing if I have a test fire with knob at 100%? I don’t know if I should have confidence in the readings being displayed but I am also not sure I feel confident/safe measuring this with my meter either.
The tube manufacturer should have provided the maximum and operating current for your tube.
We all measure these with a simple mA meter in the cathode lead of the tube. It’s about the only thing we have to go on.
On the Ruida, it operates the lps a little differently from how your machine accomplishes it. It doesn’t have a ‘pot’ to adjust the current, like yours.
I was told by a very smart UK guy to set my pwm to 50% and adjust the lps to produce 50% of the current maximum you want… I don’t think it helps you a lot as you probably don’t have a current limit pot inside your lps…
Here are some ballpark numbers for current maximums.
So I was doing a little thinking. I know that when I test fire with the physical knob set to max that I’m getting 21mA. I have tested my cuts on 1/8"/3mm plywood and found I need to set this to 7mm/sec at 40% power. This outputs 5mA on the display. According to Monport’s Lightburn manual:
So factoring 21mA times 25% I’m seeing 5.25mA which seems on target for the power recommended albeit at a much faster speed than I am seeing.
I did a test using a single line with speed set to 10mm/sec and here’s the output I saw on the power read out:
10% does not fire
15% 2mA
20% 4mA
40% 5mA
60% 11mA
80% 16mA
100% 21mA
I guess my confusion was that the percentages listed in the Monport manual was showing percentages set for Lightburn but I guess they are really showing the percentages of the total output. The other confusion I had was thinking that the Lightburn percentages would be linear in regards to power output that appears not to be the case? The jump from 20% to 40% is only 1mA but the jump from 60% to 80% is 5mA.
I see a lot of information on the K40s listing power settings in mA and this isn’t easily translatable for me to Lightburn percentages nor have I found a materials library for the Monport 40W that has these percentages in them for me to base what I’m seeing. Correct me if I’m wrong but it looks like my machine is operating as expected and it’s my ignorance to how these values relate to their mA equivalents that’s causing me to think things were not as they should be.
