Posts made by whizzard

@dc42

Thank you very much, David. I didn't even consider the "impact" differential with plastic in the nozzle. I was also always calibrating cold. I never considered plastic at the tip might soften the hit and would change the readings. I was originally posting because I was curious about the deviations other users had, and I had no frame of reference for what "normal" would look like.

I will try calibrating at temps with no filament, and it should be more precise and will probably help with the z offset deviation. Why I thought calibrating a machine cold when it only functions hot is anyone's guess. Many thanks.

@oliof said in Probe deviation / calibration questions:

@whizzard just a note that Marlin 2.1.2.2 has a lot of issues fixed in 2.1. Bugfix. I would encourage you to upgrade (requires redoing config though).

I didn't know that! I will have to update and check the notes to see what was fixed.

As far as the smart effector, it works very nicely! I can't believe I can level the whole bed consistently. I have to remember to change z probe offset when the temps are different. My bed causes interference when it is active during probing, so I added gcode to heat the bed up, turn it off, probe, and then turn the bed back on after so that it is near temps during a probe.

Here is an example:
Bed 60 Celcius: 0.62 z probe offset
Bed 95 Celcius: 1.22 z probe offset

I am guessing I should just remember that thermal expansion will change my Z, but I am surprised there isn't something in Marlin or other firmware that takes this into account. Thanks again for all the help.

@achrn
Thanks so much for the screenshots, I was super curious if I was in the ballpark or not. Seems to be getting a good level, I just have to cut my bed off during probing. I also know I am not using the board or firmware it was designed for so I am glad I can still use the effector.

@oliof
Thank you for the information! My effector came with a plastic M12 nut to attach it. The documentation mentions a fiber washer, but my effector did not have one in the packaging. I tried printing one but got better readings without it. Is the washer necessary? I am wondering if not having that is preventing flex. The standard print cooling fan is also very low to the bed and has crashed a couple times (maybe because there is no washer?)

What is the normal standard deviation that I should be getting from this probe? I know it was designed for a duet mainboard, but I have to make do with Marlin, and the programming function seems to work correctly.

Thanks again!

I just set up my Smart Effector for the first time. I have been fiddling with it since yesterday trying to get it to be as accurate as I can. Here is my setup:

Marlin 2.1.2.2
Marlin Probe Feedrate = 66mm/s fast 33mm/s for accurate probe (probe speed)
Sensitivity and programming working (flashes when I change sensitivity or reset)
Mainboard: SKR Pro V1.2 terminal accessed through Octoprint connected to the mainboard

I tried using repeatable probing and changing the speed at which the probe would tap the bed. If I set the speed of the probe slow to something like 15 mm/s, it would have more accurate probe repeatability tests, but it would "flash" twice or flicker a bit after a probe instead of one solid flash. Should I only go for one solid flash?

Setting the sensitivity high (25) would cause false triggers and failed bed probes and calibrations with slow speeds, but changing the probe speed back to 33mm/s and low sensitivity causes rather high standard deviations (I think). Here is what my tests are showing in the screenshot.

What I want to know is does the tightness of the probe matter? I have it pretty securely tightened with the plastic nut that came with the effector, and I printed a thin M12 washer where the heatsink touches the PCB because it didn't butt up to it flat without one. What should I be getting for accuracy from the probe? Is this normal (see screenshot)?

Thank you!

EDIT:
I had both a hot fan causing noise and my heated bed causing noise. I replaced the hot end fan with a few different ones and found one that doesn't interfere and I raised my probe height and added a delay to not be affected by the heated bed. After a bed level, it started printing about 3mm off the bed. I don't get why it is acting up so much for me.