Lulzbot Mini V1 Duet Maestro Conversion

General LulzBot Mini
#1

I posted this over on the Duet3d forums and it was suggested to post over here as well.

I just finished upgrading my original V1 Mini with an aerostruder and a Duet maestro 32-bit mainboard. Thanks to the open source documentation and incredibly well labelled cables, it only took two days to have it running, and only one day of software tweaking to get it printing.

The upgrade is well worth it. Overall everything is smoother, quieter, and more seamless. If you’re handy with a soldering iron, I highly recommend it, and am happy to send advice.

MVIMG_20200819_213848
MVIMG_20200819_2138483024×4032 2.49 MB

#2

Interesting. What exactly do you mean by 'smoother, and more seamless? I would like to upgrade my Mini V1 to an aerostruder but am considering converting to 1.75 at the same time. Any thoughts on that?
Thanks,
Barry

#3

I used to get stuttering problems when printing circles or fast curves because I was using Octoprint, it’s a known limitation of the usb serial connection for Marlin printers. I considered upgrading with the LCD controller, which would allow me to print off the SD card, but the Duet maestro costs only a little more, and I get to keep my network connectivity, upgrade to 32 bit control etc. TMC 2224 motor drivers have also made the printer nearly silent, apart from the part cooling fan.

By seamless I’m referring to the experience of making an STL, slicing it, uploading and printing, no faffing with an SD card or a computer tethered to the printer.

Converting to 1.75 is something I’ve thought long and hard about. Ultimately, I think 2.85 is the better diameter. Easier to print flexibles, slower extruder motor speeds, among other things. However, the availability of 2.85 is pretty disappointing. The aerostruder was well worth the upgrade, I find I have fewer issues with extrusion abnormalities, and the part cooling is much better.

#4

Thanks for your response.
My used Mini came with a complete spare printhead which looks to be identical to the one installed.
If I exchange printheads, what setup or adjustments would I need to make? The machine was not working when I bought it due to a broken wire going to the Y limit switch, but after I repaired that, it worked so well that I haven’t been brave enough to tinker with it at all.

#5

Some of the LulzBot tool heads had a sticker on the back that documented the E-steps. If you don’t have a sticker, then switching tool heads will probably require E-step calibration. Make a note of the current value (M503) and keep that with your current tool head. Swap, calibrate, and keep that value with the second tool head. You don’t need to calibrate each time you switch, just use the the value associated with the installed tool head.

Search this forum for detailed instructions for doing the calibration.

#6

Thanks. Good info :slight_smile: I would have assumed that since the extruder is gear driven that the e-steps would have been the same for identical heads. Any idea why this would not be the case?

#7

The linear distance fed for a given angular rotation of the gear is determined by the circumference of the hobbed bolt (the section with the “teeth”). There’s also a gear ratio involved but that is fixed.

For newer tool heads, the manufacturing tolerances have improved and the circumference of the hobbed bolt has tighter tolerances. Older LulzBot tool heads had a fairly large range so they were individually calibrated.

FWIW, X and Y can be computed from the number of teeth on the belt pulleys. For Z this can be determined by the pitch of the lead screw.

#8

:+1: Thanks for this. I guees one day I will have to switch heads just to test and figure out the e-steps for each. Right now everything is swell and I hate to mess with it :slight_smile:

#9

If I were you, I’d switch heads, do the calibration (if you don’t have a sticker), and then switch back with the knowledge that in case of a problem with the first tool head and a project with a time constraint, you can switch with confidence and complete your project.

#10

I most likely will do this pretty soon. The spare printhead came in a box labeled ‘Flexystruder’ and the picture it looks to be the same as both heads that I have. Can anyone tell me the difference in appearance between the Flexistruder and the regular printhead?

#11

I think you can still find pictures of the older tool heads on https://ohai.lulzbot.com/group/accessories/.