A20M overextrudes slightly at random

[walker3d]

Hey there,

We've had an A20M for about a week now and we've been fiddling with settings ever since we got it, but we can't quite seem to get it printing properly. We've fixed most of the quirks but now the printer overextrudes slightly when filling in larger pieces of print, while printing detailed parts works just fine. We've added a picture where you can see what's going on.
We're working with Cura and we think it could be something wrong with the gcode but we're uncertain. So far we've changed the flow to 102 percent from 100 because the printer underextruded in some parts causing small voids. Also turned down the speed from 60 to 55 mm/s , which helped a bit. We're also using a 3DTouch sensor for auto bed leveling, and that seems to be working just fine. We're printing using standard PLA, 200 degrees hotend and 60 degrees bed temperature.

We've attached a picture of the problem to this post, and if anyone has seen this before and knows how to fix it we would greatly appreciate it!

Thanks in advance,

Felix

[William]

Hi, Does your print range exceed the print area?

Or is the distance between the nozzle and the hotbed too close?

[walker3d]

Hi William,

No the print does not exceed the print area. Also the distance between the nozzle and hotbed is not too close, we tried increasing the distance but then we start seeing the little voids come back.

[_kaktus_]

Hello.


I'd try for a test of another filament.
Then there will be a comparison.

[walker3d]

Hi there,

we are printing the same object with the same filament on our ender 3 pro, which is printing the model great.
So i don't think it has anything to do with the filament, but correct me if there could be a difference between the printers.

Thanks in advance!

[_kaktus_]

Checkmate...

[Engineero]

I've been having a very similar issue, Really not sure how to fix it.

My assumption is that you use one extruder more than the other?

Since this printer is a mix printer, its meant to blend or swap colors constantly.

Is there a detailed schematic of the 2-in-1 out feeder?

Reason I ask, is if there is a possibility of a void somewhere inside the feeder, maybe there could be some buildup forming during extrusions into the other side of the hotend.

When I try to print with single filament, I notice this happening alot, it looks like overextrusion.

When I try to print by mixing 50/50, I get a weird effect of one side of the print getting more of one color, and the other side getting the other color more. Its like its not mixing the filaments properly.

When I do a purge wall, or tower, The color that is in standby comes out all melted like a burnt blob of filament.

A Detailed schematic of the internals would help alot in setting prime/extract/retract distances dialed in, or finding a mechanical reason for this to be happening.

[William]

Hi，I find this: https://github.com/caesar1111/Geeetech- ... UGLLw0IqLw
and you can refer to this.