Let's talk 3D printers!

djw1191 · February 24, 2023, 12:14am

How hot is too hot for an enclosure while printing PLA?

dJOS · February 24, 2023, 12:24am

Oh ok, I thought you needed modified stepper drivers and didn't realise it was a FW option now.

No. See above.

dJOS · February 24, 2023, 12:25am

You really wouldn't want to go above bed temp, ideally you want the temps as cool as possible as PLA needs a lot of cooling to get good layer adhesion.

danabw · February 24, 2023, 2:49am

Muwah ha ha ha...it has begun. Be afraid (of dumb questions), be very afraid!!! (Ominous music swells...)

dJOS · February 24, 2023, 2:50am

Noice!!!!

danabw · February 24, 2023, 6:08pm

OK, so learning intersting things about Klipper, including that in Klipper a positive Z offset is closer to the bed and negative Z offset is farther from the bed. Opposite of Marlin as far as I can tell.

Lazy question - I already have my Z Offset calibrated in Marlin, works very nicely, thank you. It's -.62.

Do I have to go through the Z offset calibration in Mainsail/Klipper again (I just did it recently and would like to be lazy), or can I just enter my known/good Marlin offset in the printer.cfg file, changing it to positive?

E.g., z_offset: .62

danabw · February 24, 2023, 8:44pm

Things are getting scarier...flashed printer to Mainsail/Klipper and I am connected. At this point I could actually break something on the printer if I do something stupid, so doing more reading...

Oh - and Mainsail has a responsive UI and formats for mobile very nicely!

djw1191 · February 24, 2023, 8:48pm

I feel like I’ve upset the 3d printing gods, went to go print out a battery storage thing, but instead of printing I got an error about a potential clog in my extruder. Gotta break out the troubleshooting guide and start taking it apart… hopefully nothing too major, I just started organizing my junk drawer!

danabw · February 24, 2023, 9:14pm

Bummer...sorry to hear that. Totally frustrating when the toys are not ready to play when you are.

djw1191 · February 24, 2023, 9:44pm

False alarm, that was quick. For some reason this PLA is suddenly brittle and broke off on the way to the hot end. Not sure why it’s suddenly brittle when the first half of the roll was fine…

dJOS · February 24, 2023, 11:12pm

No, it should be fine to carry it over.

dJOS · February 24, 2023, 11:13pm

That’s a sure sign of moisture getting into your Filament. Time to dry it out.

danabw · February 24, 2023, 11:58pm

Sorry - but just to confirm, by "No" you're saying:

I don't need to re-run calibration

And most importantly so I don't grind my extruder into my build surface, am I correct in the idea that a negative Marlin Z offset (e.g., my current -0.62) should become postive in Klipper Land (0.62)? Am I correct in the Z offset change from negative to positive going from Marlin to Klipper, or did I misunderstand that?

As soon as I have this set I'm off to do my first Klipper print! Booyah!

dJOS · February 25, 2023, 12:15am

This.

But it wouldn't hurt to re-do it anyway.

github.com

Klipper3d/klipper/blob/master/docs/Bed_Level.md#the-paper-test

# Bed leveling

Bed leveling (sometimes also referred to as "bed tramming") is
critical to getting high quality prints. If a bed is not properly
"leveled" it can lead to poor bed adhesion, "warping", and subtle
problems throughout the print. This document serves as a guide to
performing bed leveling in Klipper.

It's important to understand the goal of bed leveling. If the printer
is commanded to a position `X0 Y0 Z10` during a print, then the goal
is for the printer's nozzle to be exactly 10mm from the printer's
bed. Further, should the printer then be commanded to a position of
`X50 Z10` the goal is for the nozzle to maintain an exact distance of
10mm from the bed during that entire horizontal move.

In order to get good quality prints the printer should be calibrated
so that Z distances are accurate to within about 25 microns (.025mm).
This is a small distance - significantly smaller than the width of a
typical human hair. This scale can not be measured "by eye". Subtle
effects (such as heat expansion) impact measurements at this scale.

This file has been truncated. show original

Yes, negative is towards the bed, positive is away from the bed. So once you calibrate the Z-Offset, adding -0.025mm to that Z-offset means you are 0.025mm closer to the bed.

danabw · February 25, 2023, 12:29am

Thanks...yeah, you're probably right about re-running the calibration. Won't hurt anything and if I end up wanting to adjust it I can.

I must have an extra heaping helping of lazy genes...

dJOS · February 25, 2023, 1:41am

The SoftFever fork of Bambu Slicer looks really interesting. I might have a play with it myself.

danabw · February 25, 2023, 3:51am

Please, another slicer!? I already have enough things to think about!

OK, I do have a Klipper question, and I have Googled and cannot figure out how to set different first layer temps like I have in Prusa from your advice (so it's your fault, really).

Want to replicate below in Klipper - one set of temps for the first layer, then second set for all the rest. I'm a bit flummoxed.

I started a print I uploaded from Prusa w/those settings, but the nozzle and bed didn't follow the temp settings in Prusa, it was heating to PLA temps rather than the PETG temps that were set in Prusa for that print.

I think I may have to add M190 commands for first layer temp and first layer bed temp in the start g code in Klipper, but unsure how things then switch to the "normal" nozzle/bed temps for the rest of the print after the first layer.

djw1191 · February 25, 2023, 4:01am

My understanding was that Bambu Studio was just a fork of Prusa Slicer. I didn’t think there was a ton of extras in there above Prusa (other than the stuff they added related to their own printers).

dJOS · February 25, 2023, 5:43am

They are both forks of Slic3r.

danabw · February 25, 2023, 11:05pm

So does this math make sense to anyone else? I was doing a PROBE_CALIBRATE action in Klipper to re-confirm my Z offset.

This is how it ended up...the last position I moved to and accepted was -0.202. When I hit ACCEPT to finish that became Z offset 0.707. I don't get the math...anyone understand how this works?

Don't mind saying that Klipper is kicking my butt. Did the PROBE_CALIBRATE and tried a print and it was not good...could hear ligth rumbling of nozzle on the textured print bed and stopped the print after a little bit of it. What was laid down was more like paint than fliament, almost impossible to get off. Odd part was that I did a "looser" calibration this time (stopping when I had a little less drag on the piece of paper than the last time) yet the nozzle seemed to be too close to the surface. Thinking I might end up having to go back to Octoprint.