Hey everyone. I just wanted to share my success story of converting a TEVO Little Monster delta 3D printer (350mm x 500mm printing dimensions).

Initially, the LM comes with a knock off E3D Volcano (.4mm nozzle), a knock off E3D Titan flying extruder, and a knock off Smoothieboard called the MKS SBASE that also includes a 3.5" touchscreen LCD. I ended up ditching all of these parts in favor of genuine E3D parts, a .6mm nozzle, a Duet Ethernet controller, and a 7" PanelDue:

Prior to the upgrades, there were MANY little issues plaguing the ability to have a reliable 3D printer. First and foremost, after I purchased the printer, TEVO made the following announcement on the Facebook TEVO Little Monster Users Group:

Huh? So the printer I bought that advertised the ability to use a network connection to control it has the company no longer recommending we use it over that network connection? According to TEVO, the ethernet connection causes the MKS SBASE controller to become unstable, so it's now not recommended to use the ethernet connection for anything.

Next up is the fact that the LCD monitor has a horrible layout of information. The ability to display error messages? No can do. When the MKS SBASE encounters a runaway thermal event (e.g. when you have a strong fan blowing on the hot end and it drops the temp below the thermal watchdog threshold) the board stops completely dead and becomes completely unresponsive to your command inputs coming from the LCD.

Another issue I was not expecting is that the 32x microstepping from the DRV8825 stepper drivers on the MKS SBASE coupled with 1.8 degree stepper motors, AND a large format printer with nearly a 400mm effector arm length result in some pretty interesting ringing/texturing of parts. The 256x microstepping of the Duet Ethernet was a huge influence on going this route so that I could smooth out the surface of my prints.

Lastly, with stock Simplify3D settings, I was getting absolute crap for prints. Literally every print was inconsistent quality. I was getting a completely different print even if I immediately re-printed the same g-code. After doing this conversion, I've now concluded that I seem to have been provided with a defective MKS SBASE controller board. Given the amount of oddball issues I'm seeing on the Facebook TEVO Little Monster Users Group, I'm beginning to think there's quite a few people out there was defective controllers. On the Facebook group, you either have people posting absolutely beautiful prints coming off of their Little Monsters or you have frustration posts with people who are having an extremely difficult time printing the simplest of objects such as a 20mm calibration cube.

The conversion itself was pretty simple! I ended up drilling/tapping three out of four new holes for mounting the Duet Ethernet controller:

After that, the worst part was definitely getting the pins for the connectors installed. My 2.54mm pin crimper unexpectedly ended up snapping off the supportive tabs that hold the wire insulation, so I resorted to manually crimping each pin and then lightly soldering each crimp for better conductivity.

Once mounted and wired, the PanelDue was installed in this Thingiverse object (the 15mm model):

https://www.thingiverse.com/thing:1992124

Thingiverse object "LPA_TFT28BoxV3_FootM5" was also printed to create a strong mounting point for the PanelDue to attach to on the TEVO Little Monster:

https://www.thingiverse.com/thing:2132557

To mate the two together, I modeled up a back cover for the PanelDue case:

Once printed, cleaned up, and installed, this is the end result:

After taking a brief amount of time deciphering all of the suggestions in the BL Touch thread on this forum, I had the Duet Ethernet up and running very quickly. After making the change to a .6mm nozzle and enabling auto extrusion width in Simplify3D, here's literally the 3rd print off of the printer since completing the conversion:

The vase itself is over 450mm tall and looks absolutely beautiful!! I am beyond impressed with the Duet Ethernet controller and how simple the conversion was.

Here's the full instructions and 3d models for doing the conversion (along with the mount and case for a 7" PanelDue):

https://www.thingiverse.com/thing:2355136

Thank you to everyone on this forum who has been so forthcoming with information (especially all of the juicy tid bits in the BL Touch thread). Without it, I wouldn't have been able to do this conversion as easily as I did!!

@dc42:

Have you watched it while printing to see whether the print direction reverses at the points where you get the Z artefacts?

Are you using PWM or bang-bang control on the bed? If you are using bang-bang, try PWM.

Sorry, I meant to answer your first question when you first asked it. No reversing at all. It's going counter clockwise the entire time for the perimeter. The bed has always been under PID PWM control and there's very little fluctuation just like the hot end (no pronounced ripple that would indicate incorrect PID settings).

Let's add another twist to the riddle!! Here's a comparison of print #1 and the same slicing settings (same type of infill and everything) but thrown into Mattercontrol instead of Simplify3D:

So, now we're nearly perfect with Mattercontrol. I'm chalking this up to being a software issue, but what specifically???

No go. The machine itself is solid. There's no loose joints anywhere. Backlash shouldn't be an issue with GT2 belting that's nice and tight. Here's the latest iteration of prints:

Print #1 - XYZ cube, 400 micron, 15% infill (notice the 2 wobbles on the top/bottom and three near the middle of the X)
Print #2 - XYZ cube, 400 micron, 15% infill (printed immediately after print #1 with identical settings to show the problem is repeatable)
Print #3 - XYZ cube, 200 micron, 15% infill (wobbles are still present, but smaller thanks to the Z height)
Print #4 - smooth cube, 400 micron, 15% infill (wobble is throughout the entire cube)
Print #5 - smooth cube, 400 micron, vase mode (perfect print with zero artifacts)
Print #6 - XYZ cube, 400 micron, 15% infill, tightened all bolts/belts/pulleys (zero change to the artifact pattern)
Print #7 - XYZ cube, 400 micron, 15% infill, dropped to x32 stepping without x256 interpolation, dropped accelerations down to 500mm/sec (zero change to the artifact pattern)

From left to right, #1, #2, #6, #7

@dc42:

My guess is that the gcode generated by your slicer is printing the perimeter in the reverse direction on some layers, and that is combining with backlash or loose joints to give you the artefacts.

Very interesting observation! I've tightened everything up (I have been printing a ton lately), so that could definitely be the issue. I'm doing another set of tests now. I'll let you know my findings.

I've got a good riddle for the forum to help me figure out. I'm using my newly converted TEVO Little Monster to crank out some calibration cubes after noticing a bunch of my non-vase mode prints are some strange artifacts on the z-axis. There's two different types of calibration cubes and how they look with different settings:

Print #1 - XYZ cube, 400 micron, 15% infill (notice the 2 wobbles on the top/bottom and three near the middle of the X)
Print #2 - XYZ cube, 400 micron, 15% infill (printed immediately after print #1 with identical settings to show the problem is repeatable)
Print #3 - XYZ cube, 200 micron, 15% infill (wobbles are still present, but smaller thanks to the Z height)
Print #4 - smooth cube, 400 micron, 15% infill (wobble is throughout the entire cube)
Print #5 - smooth cube, 400 micron, vase mode (perfect print with zero artifacts)

Pictures (the forum doesn't allow you to zoom in on the high res pictures, so copy the image location into your browser to see the full picture):

I tried dropping instantaneous speed changes down to half of what they originally were (1200mm/min) when I did my initial Duet conversion. That didn't change the quality of the print at all. Also, the hot end and bed temperature graphs are not showing fluctuation. Watching the numbers on the hot end, I'm seeing a fluctuation of about .5c, so my PID settings are pretty tight and that shouldn't be causing such heavy wobble.

config.g Drive settings:
; Drives
M569 P0 S1 ; Drive 0 goes forwards
M569 P1 S1 ; Drive 1 goes forwards
M569 P2 S1 ; Drive 2 goes forwards
M569 P3 S1 ; Drive 3 goes forwards
M350 E32 I0 ; Configure microstepping without interpolation
M350 X32 Y32 Z32 I1 ; Configure microstepping with interpolation
M92 X160 Y160 Z160 E837 ; Set steps per mm
M566 X600 Y600 Z600 E3000 ; Set maximum instantaneous speed changes (mm/min)
M203 X39960 Y39960 Z39960 E3000 ; Set maximum speeds (mm/min)
M201 X1000 Y1000 Z1000 E1500 ; Set accelerations (mm/s^2)
M906 X1800 Y1800 Z1800 E1500 I30 ; Set motor currents (mA) and motor idle factor in per cent
M84 S30 ; Set idle timeout

Any help/insight into the problem would be greatly appreciated!! Thanks in advance!

@minim:

Are you happy with the dimmensionall accurancy of the printer? I have a spare Duet wifi and im dreaming of a delta Even if i got parts for a big Core xy on MGN rails on the bench ^^ Delta's Looks so cool!

I am. I've been comparing the setup to my SeeMeCNC Rostock MAX V2, which has been my bulletproof printer that cranks out my my accurate prints. So far, the TEVO with a Duet is within a 15-20 microns. Not bad for something I haven't tweaked at all compared to the Rostock that I've spent a significant amount of time dialing in over the past year.

Sorry for taking so long to post this, but here's the complete conversion instructions and 3d models for the conversion:

https://www.thingiverse.com/thing:2355136

@inachisiojexus:

@kenavn:

There wouldn't be any show stoppers in regards to only switching the controller, but keeping the original extruder and volcano?

The only incompatibility I've thought of is that I believe that the stock optical endstops use 5V, while Duet WiFi/Ethernet expects them to run on 3.3V.

Hopefully somebody who knows more can chime in on this.

(it's probably not a big deal to take 5V from GPIO or something, in any case)

I thought of this as well, but thankfully, it appears the stock optical endstops are working just fine on 3.3 volts. Homing is working perfectly without further modification.

Hey everyone. I just wanted to share my success story of converting a TEVO Little Monster delta 3D printer (350mm x 500mm printing dimensions).

Initially, the LM comes with a knock off E3D Volcano (.4mm nozzle), a knock off E3D Titan flying extruder, and a knock off Smoothieboard called the MKS SBASE that also includes a 3.5" touchscreen LCD. I ended up ditching all of these parts in favor of genuine E3D parts, a .6mm nozzle, a Duet Ethernet controller, and a 7" PanelDue:

Prior to the upgrades, there were MANY little issues plaguing the ability to have a reliable 3D printer. First and foremost, after I purchased the printer, TEVO made the following announcement on the Facebook TEVO Little Monster Users Group:

Huh? So the printer I bought that advertised the ability to use a network connection to control it has the company no longer recommending we use it over that network connection? According to TEVO, the ethernet connection causes the MKS SBASE controller to become unstable, so it's now not recommended to use the ethernet connection for anything.

Next up is the fact that the LCD monitor has a horrible layout of information. The ability to display error messages? No can do. When the MKS SBASE encounters a runaway thermal event (e.g. when you have a strong fan blowing on the hot end and it drops the temp below the thermal watchdog threshold) the board stops completely dead and becomes completely unresponsive to your command inputs coming from the LCD.

Another issue I was not expecting is that the 32x microstepping from the DRV8825 stepper drivers on the MKS SBASE coupled with 1.8 degree stepper motors, AND a large format printer with nearly a 400mm effector arm length result in some pretty interesting ringing/texturing of parts. The 256x microstepping of the Duet Ethernet was a huge influence on going this route so that I could smooth out the surface of my prints.

Lastly, with stock Simplify3D settings, I was getting absolute crap for prints. Literally every print was inconsistent quality. I was getting a completely different print even if I immediately re-printed the same g-code. After doing this conversion, I've now concluded that I seem to have been provided with a defective MKS SBASE controller board. Given the amount of oddball issues I'm seeing on the Facebook TEVO Little Monster Users Group, I'm beginning to think there's quite a few people out there was defective controllers. On the Facebook group, you either have people posting absolutely beautiful prints coming off of their Little Monsters or you have frustration posts with people who are having an extremely difficult time printing the simplest of objects such as a 20mm calibration cube.

The conversion itself was pretty simple! I ended up drilling/tapping three out of four new holes for mounting the Duet Ethernet controller:

After that, the worst part was definitely getting the pins for the connectors installed. My 2.54mm pin crimper unexpectedly ended up snapping off the supportive tabs that hold the wire insulation, so I resorted to manually crimping each pin and then lightly soldering each crimp for better conductivity.

Once mounted and wired, the PanelDue was installed in this Thingiverse object (the 15mm model):

https://www.thingiverse.com/thing:1992124

Thingiverse object "LPA_TFT28BoxV3_FootM5" was also printed to create a strong mounting point for the PanelDue to attach to on the TEVO Little Monster:

https://www.thingiverse.com/thing:2132557

To mate the two together, I modeled up a back cover for the PanelDue case:

Once printed, cleaned up, and installed, this is the end result:

After taking a brief amount of time deciphering all of the suggestions in the BL Touch thread on this forum, I had the Duet Ethernet up and running very quickly. After making the change to a .6mm nozzle and enabling auto extrusion width in Simplify3D, here's literally the 3rd print off of the printer since completing the conversion:

The vase itself is over 450mm tall and looks absolutely beautiful!! I am beyond impressed with the Duet Ethernet controller and how simple the conversion was.

Here's the full instructions and 3d models for doing the conversion (along with the mount and case for a 7" PanelDue):

https://www.thingiverse.com/thing:2355136

Thank you to everyone on this forum who has been so forthcoming with information (especially all of the juicy tid bits in the BL Touch thread). Without it, I wouldn't have been able to do this conversion as easily as I did!!