Ghosting on text

So I am printing ABS, 0.15 high detail, and on verticle walls with text (3 -5 mm text embossed -0.45) I get ghosting.

New printer (sidekick 747 with 1.75 v2), I’ve checked the tension, I’ve put the printer on a 120 lb patio brick which is on top of about 1/2" of rubber matt.

I suspect it is an issue with one of the default cura settings that is more high speed than high detail.

Any guidance?

Change “outer wall speed” to a lower value, play around with it until you get a proper balance of speed and ringingless surfaces.

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Thanks. I am doing a test print with default settings for now of this:

I am posting it in case there is anything in the design that is obviously wrong to the experienced. The minimum wall thickness is 1 mm even after the text emboss.

I am probably naive but I think it looks like I am going to spend far more time and material on test prints than actually using the 3D printer.

In the beginning this may be true (although you are using the printer, just not for objects you expected). Over time there will be less test prints and more actual prints.

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@glebbb
Well, right before my test print, I checked the thumb screws that hold the y-axis assembly, and snugged them up. And my test print printed okay as far as ghosting or mechanical ringing goes.

I have another issue…which is bed adhesion. The purple stick school glue was working okay, but I heard the Magigoo for ABS was even better. It doesn’t seem to be better though for this test print…so I am off to print my other design that worked with the purple stick school glue with the Magigoo. We’ll see.

Thanks for your suggestion, though…I bet it would have helped if necessary.

@b-morgan
That’s one way to look at it. The good news is this reminds me of the wild west early days of PCs, so that is exciting. Lots of room for improvement in the technology as it stands.

Well, I got the octolapse working…using default settings.

The lighting and camera placement is not the best, but in the video, the right rear from the perspective of the camera (back left from front of printer) did not adhere to the bed.

RingingTest v5.stl (206.7 KB)

This is the STL file I created for the ringing / ghosting test, in case anybody else finds it useful.

ABS sticks great to PEI at 110C… no need for the glue stick.

Also make sure the print cooling fan is off for the first mm of ABS prints. Then use minimal cooling otherwise the cooling of the ABS may cause warping.

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Thanks for the response! I wish I had the same experience. Well, it does stick great, when it doesn’t warp. Very difficult to get off at that point (so the magigoo supposedly acts as a release agent too).

Should I change the settings from the default settings in cura (as configured by lulzbot)?

This is what it is set to right now for the Lulzbot ABS (IC3D) high detail settings:

image

Thanks again for your help

Can you post a picture of the bottom of the print… the side touching the bed? The filament lines can tell if nozzle height is properly set.

I’m not very familiar with Cura’s Cooling settings. I’ll describe what I do in S3D, maybe its easy enough to replicate in Cura… or someone more familiar could help.

My print layer height is normally .3, and I like to keep the fan off for the first 3mm of the print. To achieve this, I set fan speed to 0 for layers 1-10. Then set the fan speed to 8% at layer 11 and keep it consistent for the rest of the print to help Z dimensional accuracy.

A few more tips for adhesion (which typically happens when air gets under the print… a drawback of a moving bed):

  • Cooling the first layer naturally will help it stay stuck to the print bed.
  • Use a 5-10mm brim (with a thickness of .5mm) to increase the contact area with the print bed.
  • Corners on boxes are notorious for lifting. If the corners continue to lift even with the brim, add thin discs to help anchor. Create a 20mm disc with a thickness of 1mm and place them under the corners of the object in Cura.
  • Lastly, try rotating the box by 45 degrees in the Z-axis. Sometimes this helps the airflow around the object.

Sorry to sidetrack your original issue of ghosting (which can usually be remedied by slowing the outer perimeter down). Hope some of these help with your adhesion issues.

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My last print did not warp, but here are two images from the bottom. One is the left side of the object, the other was the right. It was printed slightly right of center of the bed.

Of course this is a moving target. I changed the bottom to have less material. Also I pre-heated the bed at 60C for a half hour or so in an enclosure before starting the print. And I had a clean application of the magigoo (cleaned bed, then applied fresh when bed was cold).

Also, the bottom holes were enlarged and turned into octagons, and I change the default travel settings to this:

image

Which seemed to help make the holes more consistent with smaller start defects on some of the holes.

The print immediately prior to the above warped in one corner, and also seemed to have trouble making a clean bottom layer (but the design was slightly different). The design and settings changes above were to get rid of some of the other issues illustrated below.

Also, I am wondering if my bed needs a different z offset for different parts of the bed. I thought that is what the bedleveling feature was for but maybe 16 sample points is not enough?

Sorry to sidetrack your original issue of ghosting (which can usually be remedied by slowing the outer perimeter down). Hope some of these help with your adhesion issues.

No problem. I am going to get back to the embossed text next.

But first and just for fun and without expectation that it will be helpful, here is an octolapse with better resolution of the square/octagon print earlier in this post:

The z-height on the hexagon bottom layer looks good, the circles may need the nozzle to be closer to the bed. If those are different parts of your bed, definitely note the difference for future reference. If you didn’t adjust anything between those prints, then check the auto level discs for any debris or film from leftover filament.

Last trick I have for you is to print a “wall” surrounding the base. I do this with the multi-process feature of S3D, specifying the bottom 8mm to have a tall skirt or a ooze shield if a dual extruded is configured. You shouldn’t have to do this with an enclosure… since not much moving cool air.

If that’s the magnetic bed, try one of the $30 PEI powder coated spring plates on Amazon. ABS sticks to the, extremely well… ooze from the nozzle will stick to the plates.

Well good luck on the journey to learn your machine… you seem on the right track.

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How does this work? Will the disks break away?

Anyway, I am not starting to wonder if it is my bed feet to the table. Only two touch at a time. The main frame all four touch and seem to be as short as possible. I’m checking with support on this.

What do you think of a BuildTak print surface? How does it compare to the “$30 PEI powder coated spring plates” you mentioned?

I have a magnetic bed but I am using the glass bed PEI side for now.

Anyway, I am trying to get to the point to be able to rapidly prototype electronic enclosures, and while I am not giving up yet, I am starting to wonder if I should not have just gone with a professional model instead of the sidekick 747.

Yes, the discs would just break off like having a brim… which is essentially the same but could be more work to post process (sanding). Boxes definitely benefit from a 45 deg rotation and a brim or discs to anchor the corners.

I haven’t used buildtak products, but I’ve heard they work great and eventually wear out. The powder coated PEI spring plates are relatively cheap and work well.

The printer should definitely level and stable. While you work with support, I would shim the corners to make things stable, I’m not familiar with the construction of the sidekick, if it’s based on 2020 extrusions, loosen the screws that secure the corner connectors, straighten out the frame and tighten the screws.

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I just found this video that illustrates a lot of what you said. The pace is slow but it is otherwise a good video:

Just a follow up. I did verify that the disks seem to work to prevent warpage. So I have that up my sleeve. I am testing a different approach by removing material to break up the long edge lines that were leading to the temperature shrinkage and warpage right now. Hopefully that will work. But if not, the disk idea does work, as you say, if you can tolerate the extra post-processing.

Okay, so my experiment to break up the long edges was a partial success. It seemed to help, but the features I added to the design to break it up were too thin. So now I change the design and am printing again. I feel like I am getting close.

Also, I am backing out of some of my other changes, such as using magigoo on pei. I am using the school glue for now, because it seems to help release. In the past I have had major problems getting the print to release from the bed without scraping the bed up.

Glad to hear you’re making progress.

For ABS, try to find a balance with just the PEI. Maybe a Z-height adjustment in the start script:
G92 Z0.1; Lower by 0.x
Use a negative value to raise the nozzle a bit.

Quick tip for the model removal: Let the bed cool to 50C and use a tool to help remove the print from the bed. I like the wide paint spatula tool to slip under the print and move around the model to release… using a second tool helps for large prints.

In any case, sounds like you’re getting along pretty well. Good job!

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Thanks. It doesn’t help that I am simultaneously learning fusion 360–which I am really starting to like for the things I am doing.

So my last print was a total success. Now I am running a test with 9 prints to see what sort of yield I will get.

Is 50C a lot better than a 60C bed to remove? With the glue, I was able to twist off my last two prints, and they weren’t warped.

I switched from SketchUp to F360 3years ago. Still learning, but definitely a better platform for 3D printed models.

60C should be fine, but 50C helps the PEI adhesive to remain stuck to the glass.

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