/vl-ba-3d-print

Helpful stuff for 3D printing in the BA office.

VL BA office 3D-printing manual

We are caring for a good ol' trusty Prusa i3 MKS generously provided by @mirosko 🧡.

You can usually find it in the kitchenette area on the 7th floor near the game room.

❓ How it works

Currently, using the printer is free-for-all, meaning that if the printer is not printing (and it doesn't have a sticky-note with some kind of a warning on it), you can use it.

Feel free to edit this manual if you feel something's not right.

🤝 Having someone else print stuff for you

Message #ba-3d-print slack channel, asking nicely and attaching a model (.stl mesh file) you want to have printed. Check the spools around the printer to see which colors are available.

Most common websites with a huge database of models are Printables and Thingiverse.

Printing stuff yourself

  1. Slice the mesh (.stl) file using PrusaSlicer and put the exported gcode on the printer SD card.
  2. Hit Print from SD and choose your model.

⚙ Setting up PrusaSlicer

  1. Check out this Prusa guide if you haven't already.
  2. Install PrusaSlicer.
  3. Download the recommended config bundle and import it to Slicer via File > Import > Import Config Bundle. This will do most of the configuration for you, so unless you want to do some tweaks, you should be ready to slice.

🔪 Slicing

Most of the time, you simply:

  1. Drag-and-drop your .stl model(s) into PrusaSlicer.
  2. Optional: if your print has sharp outer corners, you might want to configure Print Settings > Skirt and brim > Brim.
  3. Hit Slice now
  4. Hit Export G-code

🔀 Switching the loaded filament

  1. Choose Preheat (PLA) from the main menu and wait until the target temperature is reached.
  2. Choose Unload the filament from the main menu.
  3. ⚠️ Secure the loose end of the filament you just unloaded!
    When unloading the filament, don't let go of it until it's secured in the spool frame. Otherwise, the filament might become tangled - it's hard to notice, and it might do damage to the print, or worse, the printer.
  4. Before loading new spool, first clip off the tip if it is bent/deformed.

❄ Removing completed prints

  1. Wait until the bed cools down. This is not so much to protect your fingers (you should handle the bed temperature for PLA without issues), but removing the print while it's still hot will most likely cause it to bend as it cools.
  2. Use the red scraper near the printer to remove the print.
    ⚠️ Never use any sharp objects to do this!
    Most of the prints can be simply pulled off from the bed, but the larger the contact surface with the bed, the harder it will be.

🧽 Cleaning the bed

Occasionally clean the print bed with a paper wipe and a bit of isopropyl-alcohol. This usually helps if your print failed due to first layer not sticking to the bed.

💡 Practical tips

🔩 Screws

Here's some advice for working with screws in your design.

📏 Screw sizes & Taping sizes

🔗 ISO Metric Thread dimensions The diameter of the holes in your model should be "Tapping Drill (mm)".

🗒 Printing experience

When slicing, set Number of perimeters at least to 4 so that the screws have enough support.

Using 0.4 mm nozzle and 0.2 mm layer height, these are the actual printed hole dimensions:

Diameter
in model		 Printed
diameter		 Ratio Fit with M3.5 Self-tapping
screw (samorezka)
2.9 mm 2.2 mm 0.76 Difficult to screw, but it worked
3.2 mm 2.9 mm 0.91 Perfect fit
4.0 mm 3.5 mm 0.88 -

💔 Common issues

Print not sticking to the bed.

Try cleaning the bed.

SD card is not detected

Pull the SD card out, and put it back again, gently. This printer likes it slow.

Filament won't load

When you select Load filament, keep holding the filament and push slightly down to help the loading. The printer likes this part a bit rougher (but don't force it too much).