Can I fix these lines or is it a limitation of the printer?
 

Can I fix these lines or is it a limitation of the printer?  

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keeley
(@keeley)
Active Member

Hi,

I will start with the question with additional background details below.

I modeled and printed this box (pics attached).  It prints in place with the box open with no supports so the bottom and top of the box are flat on the print bed.  The problem I have is that the layers on the side of the box with the different color text shifted around.  Mostly it looks like they shift in towards the inside of the box.  If you feel the lines inside the box they are mostly shifted inwards.  At first I thought it was under extrusion but realized all the material is there, just shifted about.  I don't think it is a hardware shift problem with the printer motors or tracking since as you can see the other half of the box that prints on the same layer is smooth and beautiful (except it looks like I need to increase the wipe a bit going from orange to yellow as the yellow has a slight orange tint to it from an insufficient wipe).  I was was pleasantly surprised that it printed the text so cleanly with the fine detail in the serifs, but quite dismayed at the layer lines.  Any ideas of how to fix this or is it just how the current software works with how I have this modeled and the given direction of printing.  

Print Material: PLA (Yellow is eSun PLA+ Pro, orange is Prusament) (I used the Prusament default settings for both brands of PLA, I have found that the Prusament settings work just fine for me when using the eSun PLA+ Pro filaments)

Settings: Default 0.2 mm quality layer height with two changes.  1. I changed it from 2 to 3 perimeters and 2. I turned on bridge detection so the pins inside the hinges print correctly.

Tool changes: 80 (all went without a hitch, 11 hour print with no faults or any problems with filament loads and unloads)

Quick background. I have had my MK3S for about 6 months. It is my first 3D printer.  I bought the kit along with an MMU2S kit and assembled just the MK3 first.  It was running beautifully for months so I finally decided I knew enough and was confident enough in the printer to assemble the MMU and upgrade my printer.  It went well and I printed out the two color sheep using the supplied g-code and it looked great to me and the printer continues to spit out high quality single color prints.  Big sigh of relief there.  

I modeled the box in Fusion 360 using a great print in place hinge design I got from Kevin Kennedy who does Fusion 360 tutorials on youtube.  I added some text in a different color in the front and was surprised at how smoothly the g-code creation went.  I imported the two stl files together into Prusaslicer and it recognized and arranged them correctly and assigned extruders.  

Posted : 15/08/2020 2:35 pm
jsw
 jsw
(@jsw)
Prominent Member

It looks to me that the extrusion is  inconsistent, both in general and right after a filament change.

I would first try increasing the wipe quantity, quite a bit.

Posted : 15/08/2020 6:50 pm
keeley
(@keeley)
Active Member

@jsw

Thanks for taking a look.  I will see if that helps.  My first thought was under extrusion but when looking at the layers it seems that there is plenty of material, it is just shifted towards the inside of the box.  I don't have a photo of that part but each one of those indented layers on the outside has a corresponding extrusion on the inside.  If I could just align the layers vertically they would be smooth so I don't think there is under extrusion. The layers are shifting so that the band of messed up layers is a palpable lump all the way around on the inside. 

Posted : 15/08/2020 10:41 pm
jsw
 jsw
(@jsw)
Prominent Member

One good sanity check might be printing the 'basic box' without the lettering, comparing the relative quality without the umpteen filament changes.

Posted : 16/08/2020 9:44 pm
keeley
(@keeley)
Active Member

Thanks, yes it prints fine without the text.  I guess I won't worry about it too much and will avoid printing text vertically in thin walls going forward or will do some more testing on the text part in the future if doing something like this again.  It was necessary to get this thing to print in place without supports however.  If I do it again I will have the hinge print in pieces and glue it together which will give me more flexibility in lid height and print orientation so I can print the text flat against the printer.  I have done that quite a bit with no issues and then  I would only have 6 or so tool changes instead of 80 as well.  Once again thanks for your time.  

Posted : 17/08/2020 1:19 pm
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