Hologram Pi-ramid - 3D printed parts and initial assembly

Enrico,

Thanks for this. I have tried some of these ideas in the past, but unfortunately now I cannot remember what worked well and what didn't. I guess I'll have to start again and write it down this time.

Dubbie

Luis,

These are some good ideas. I will have to try them out. I did reduce the infill on some of the more recent parts, as you suggested and it seems to have printed much better. Or it may be that the bed was heated properly as the printer was on for a long time.

Dubbie

Thank you Shabaz, I'm glad you liked it!. If you ever need one, it is shared on thingiverse. I have a metal one but to be honest I find the 3d printed one easier to handle for for very soft materials as it doesn't add significant weight mostly at the beginning.

Luis

Hi, despite the fact that the shell thickness should be a multiple of the nozzle diameter - for an obvious reason - I use a higher thickness just for the parts that need some post-production like sanding then painting, eventually. But I also saw other interesting methods like using a solvent to make the printed surfaces smooth that - as these methods consume partially some plastic material - it is a good idea to keep the shell thicker.

Enrico

Hello Dubbie,

I think 85% infill is high as a default/for average parts, usually you will need something around 15% to 20% just to give some internal volume to the parts and also to help features of the object that are not vertical -or tend to be horizontal- to have something to hold on to when printing. Usually an infill that high is needed in very specific cases like when parts will be under heavy tension/pressure, etc.

If your parts are cracking that most likely is poor layer adhesion, I had the same issue with my Creality CR-10S -brand new and with factory default setting- which is the printer I'm using for this project. try checking the following in that order:

• Printing temperature: may be too low for the material you are using. Google "temp calibration tower" useful to find the right temperature for your material. It's better to have the temp on the high side a little bit.
  
• Underextrusion: This video will help you calibrate extrusion amount. You can try correcting it with gcode M92 to avoid doing it with a firmware change
• Check the Z-axis: again calibration... are objects as tall as they should be?. A calibration cube works well here

• Bed temperature: try increasing it a little (maybe 5 degrees)

• First layer: Making sure your first layer bonds well to the printing is the key for good bed-to-part temperature transfer (if you have a heated bed) and also will help other layers bond better. What I personally do here is I level the print bed as good as I can then I print  just the first layer of a mid to big part, then I take that layer and visually check if every line extruded is bonded well to the next in every spot, If not, then I try to the move bed closer to the nozzle -only the corners that need it in little amounts-. Calibration has to be done regularly and when done, heated bed and nozzle must be hot.
  

I tried all of the above with good success -picture below for results-, layers have now a very strong bond and parts won't break easy.

Hope this helps

Luis