Settings for crisp alphanumeric and small hole cutouts please

[Airspeed 0]

Hi,

I'm using an Ender 3 V2. I need to 3d print flat objects with cutout alphanumerics and the occasional 1mm hole. Once or twice, the print was excellent, but then the printer ignored ALL of the cutouts and printed flat discs. I uninstalled the CURA that came with Ender, and installed from the Ultimaker site. I am getting some cutouts, but they are smudgy. The raised features look OK, but the indentations do not. The cutouts are in the 2x2mm to 3x3mm range, and holes 1x1mm. My single decent print was in the wrong colour, and when I have tried black, which seems fine for everything else, the results are useless. Picture attached.

Using 0.4 nozzle, 0.12 layers. I have 0.2 nozzles available. Thanks for reading, regards, Mike

[GregValiant 1,351]

If you can share the model then post it here.  I've done a lot of printing with both raised letters and relieved letters on my Ender 3Pro.

If the 1mm features are round they will be tough because the filament always wants to pull towards the center and that will make them smaller or disappear all together.  Minimum letter width is about nozzle diameter for raised letters.

 

[geert_2 558]

For tiny holes, design them bigger (1.5mm to 2mm) and then go through them with a *manual* drill.

 

For text: you can't easily do tiny, clean cut-out letters: for example in the letter "M" or "W", the nozzle has to come into the letter to fill the white-space. But that infill can only have the width and roundness of the nozzle, even less, and thus tends to spread and destroy the vacuum of the character-legs. It is like printing inverse text (white on black background) with poor quality black ink on poor quality recycled paper: much of the text is lost due to the ink spreading into the white areas.

 

Thus cut-out text looks worst of all. If possible, try raised text: then the nozzle just has to follow the lines of the text-legs. It still looks clumsy, but way better than recessed text. A solution in-between is to lower a rectangular area, and in that recessed rectangle, place your raised text. This is often done in injection moulding.

 

I made test-text models a few years ago, for all sorts of texts: recessed, raised, hollowed-out (watermark), etc. Feel free to try them and play around with them. See here (and then scroll down a bit):

https://www.uantwerpen.be/nl/personeel/geert-keteleer/manuals/

 

Anyway, for best results printing fine details, print slow, cool, and in thin layers. For comparison, also print it fast, hot, and in thicker layers once, to see the difference. Printing it in a material that flow well like PLA also gives better results than more elastic materials when hot like PET.

 

Raised text (all characters in these photos are 3.5mm caps height, text legs are 0.5mm width):

 

Hollow watermark, thus sitting totally inside the model (idem: 3.5mm caps, 0.5mm legs). Works only with transparent or well translucent materials obviously:

 

Hollow watermark text, this time vertical, top one chemically smoothed, bottom one as-printed:

 

Use this to go through tiny holes manually to clean them out. This method gives good feeling, enough torque, and does not melt the plastic: