Anycubic Mega X control problems

[CJSteamer 0]

Hi, newbie here, and I'm just starting to use a new Anycubic Mega X printer, which installed Cura as its control software. When asked, I updated to the latest Cura version (4.6.2).

 

I can open STL files and set basic things, and send to the printer. What I'm having trouble with is setting flow rate (and I think speed, probably other things). For example, I adjust flow rate in general, and see that it's propagated to the various things using flow rate, and then Print. But the line of material remains super thin; and I can feel it tugging along into the feeder motor at the same rate, without change. I've bumped it up to 150%, no change.

 

Is there something I have to do to make the printer allow this control? Or something else I'm missing? 

 

Thanks for any pointers!

 

  

[GregValiant 1,266]

I don't know much about that printer.  Looks like an open frame design likely running Marlin firmware.  There are general things that can be checked though.

Check within Cura and find the filament diameter.  Make sure it is set to 1.75mm.

Check that the "Firmware Flavor" matches your machine (Marlin?).

Check that the nozzle setting reflects what you actually have installed.

If the printer came with an SD card are there sample Gcode files on it?  I would start by printing one of the samples to make sure everything is working as it should.

It looks like the machine has an adjuster for filament tension on the extruder.  Make sure there is no slippage there when extruding.

Have you calibrated the steps/mm of all 4 axis?  If the printer is told to push 100mm and it only pushes 90mm then there will be under-extrusion.

When you change the Flow in Cura, all the other flows should update to match it.  Double check "Initial Layer Flow".  Make sure that one matches the rest of them.

 

There are downsides to printing over the USB.  I much prefer using the SD card.

 

[CJSteamer 0]

Thanks very much Greg, some of those I've done, but a couple I haven't so I appreciate the checklist.

 

The machine uses Marlin, I'll check Cura.

 

Question, when you write the gcode to the card from Cura, and use that, is it not giving the same instructions as over the USB? I experiment with the card though, and see if there's a difference.

 

Thanks,

Cliff

 

 

[GregValiant 1,266]

They are the same instructions.  Using Cura (or Pronterface) as a host software works OK at best.  There is no way for host software to check how fast the printer is using lines of Gcode (circular features mean lots of moves/second and lines of code/second.  Large flat areas mean few moves/second and few lines of code/second.) so the host struggles keeping up at high usage, and sends too much info at low usage.  It's a tough balancing act.

Cura and Pronterface also ask the printer for temperature information every 3 seconds which means constant 2-way communication through the same line that the gcode is using.  With the SD card the printer just pulls lines at the rate it needs them.  Then there is the problem of Microsoft updating something during an all-night print and the computer re-boots causing the print to stop.  That doesn't happen from the SD card.

[CJSteamer 0]

Thanks very much for those insights, Greg! 

 

I've been printing from the card all day, same file multiple times, with only one update to the file between things; and it's been great knowing the computer's well being isn't a factor.

 

[GregValiant 1,266]

There is a definite learning curve.  You've got the design software, slicing software, machine firmware, Gcode language, the mechanical aspects of the machine, etc.  It's a lot of stuff and it all has to come together for a good print.

Download a calibration cube from Thingiverse (there is a link from within Cura under Extensions / Thingbrowser) and you can slice it using various settings in Cura and see how they effect the print and each other.

Spiralize Outside Contour is pretty cool.  Some folks call it vase mode.  There are some nice purpose built vases on thingiverse, but you can use it on a calibration cube just as well.

 

[CJSteamer 0]

Thanks again Greg, I'll try those.