Beginner Needs Help - Anycubic Kossel Plus + Duet WiFi -- HOW?

dc42

@mindbender9 said in Beginner Needs Help - Anycubic Kossel Plus + Duet WiFi -- HOW?:

G31 X0 Y0 Z20 ; POSSIBLE PROBLEM WITH Z=32.82

It buries the nozzle in the bed because you are telling it that the IR sensor triggers when it is 20mm above the bed (Z20 in G31). The actual trigger height will be much lower than that. Measure the IR sensor trigger height and use that value in the G31 Z parameter instead.

mindbender9

@dc42 said in Beginner Needs Help - Anycubic Kossel Plus + Duet WiFi -- HOW?:

Measure the IR sensor trigger height and use that value in the G31 Z parameter instead.

~~When you say to measure the trigger height for the IR sensor, what height would that be? Is that the Z-position from the bed to the bottom of the sensor? But at what height? I'm don't understand.~~

Edit: I'll go over the "Measuring the trigger height" section of your instructions when I get home. Thanks!

One other question:

The G31 line from the bed.g file says:

G31 X0 Y0 Z20

While the config.g line has:

G31 X0 Y-32.82 Z0 P500

Question: Should the two G31 lines match in both files?

Thanks for your help!

mindbender9

So I performed a number of Trigger Height measurements tonight and only two of the ten tests were even close. I don't understand why there's such a variance between the numbers.

Z-Height #1: 2.377
Z-Height #2: 3.953
Z-Height #3: 2.641
Z-Height #4: 3.09
Z-Height #5: 3.391
Z-Height #6: 4.415
Z-Height #7: 2.103
Z-Height #8: 3.628
Z-Height #9: 3.653
Z-Height #10: 3.516

Now, two of the Auto Calibration points land outside of the bed. And I'm unable to change these outside positions no matter what G1 Xx Yy Z99999 H0 values I save to the bed.g file. It's like the board isn't reading the bed.g file. What happened?

What do I do now?

dc42

Is the variance is between probing at different points? If so then on a delta printer this is generally caused by the tilt of the effector varying with XY position. The tilt causes the relative heights of the nozzle and the prove to vary with XY position.

Inconsistency in the trigger height for the IR sensor can also be due to using a transparent bed surface (e.g. glass or PEI) that is not backed by a black surface, or that has scuff marks on the top.

If your initial delta parameters are a long way out, that could cause probe points to be outside the bed limits. Try a smaller probing radius. You can always move some of the probe points further out when you have it working.

mindbender9

@dc42 said in Beginner Needs Help - Anycubic Kossel Plus + Duet WiFi -- HOW?:

Is the variance is between probing at different points?

All points were for the same position. Dead center, at the middle of the bed.

Inconsistency in the trigger height for the IR sensor can also be due to using a transparent bed surface (e.g. glass or PEI) that is not backed by a black surface, or that has scuff marks on the top.

Using a replacement black bed top from the manufacturer.

If your initial delta parameters are a long way out, that could cause probe points to be outside the bed limits. Try a smaller probing radius. You can always move some of the probe points further out when you have it working.

Will do. I’ll reduce the quantity of probe points using the wizard and see what happens.

Question for @dc42 - What should be entered for G31 in the bed.g file? Should the XYZ values match the config.g G31 line or should they be zeroed out?

dc42

@mindbender9, please clarify what type of Z-probe you are using. I was assuming it was my own IR sensor, but skimming through this rather long thread, I found user @3mm mentioning the IR sensor but no confirmation that you are using one too.

mindbender9

@dc42 said in Beginner Needs Help - Anycubic Kossel Plus + Duet WiFi -- HOW?:

@mindbender9, please clarify what type of Z-probe you are using. I was assuming it was my own IR sensor, but skimming through this rather long thread, I found user @3mm mentioning the IR sensor but no confirmation that you are using one too.

Hi @dc42 - The IR sensor that I'm using is the "Mini differential IR height sensor" - I believe this might be one that you designed.

It is currently mounted on my hot-end with an offset of 32.82mm (distance from the nozzle).

dc42

Thanks. To measure the trigger heights, did you set Z=0 using the paper test and G92 Z0, and then repeat G1 Z5 and G30 S-1 multiple times, recording the reported trigger heights? If so then you should get results consistent to within about 10um assuming your mechanics are running smoothly and you haven't use an excessive probing speed, or accelerations that are so high as to cause missed steps.

If you are still using F1000 in your M558 command, try a lower setting such as F200.

mindbender9

Hi @dc42.

Yes, I followed the exact directions found in the documentation for "Measuring Trigger Height" here. Yet somehow, I received all sorts of values from measuring the same dead-center spot.

I'm wondering if my printer is in the Bermuda Triangle.

I'll change the M558 F value to F200 tonight.

Question: In the bed.g, what should the G31 values be? Should the XYZ values be equal to zero or something else (e.g. should they match the G31 line from config.g)?

Thanks @dc42

dc42

You don't need a G31 command in the bed.g file, just the one in config.g.

Juice

Consider calibrating the printer without using the probe just to get you up and running, It only takes five minutes. It will eliminate any probe inconsistencies and you can always come back to the probe later to tweak that last bit of accuracy.

Danal

@juice said in Beginner Needs Help - Anycubic Kossel Plus + Duet WiFi -- HOW?:

Consider calibrating the printer without using the probe just to get you up and running, It only takes five minutes. It will eliminate any probe inconsistencies and you can always come back to the probe later to tweak that last bit of accuracy.

Agreed! If you set you config.g so that there is NOT a probe configured, when you run the probe command, pop-ups will occur on the web interface that will guide you through "paper probing". This will get you going...