Why do I get these weird mesh artefacts?

I'm really trying hard to follow these step by step. I'm using version 3.5.0. I'm at part 4 of this tutorial (creating the cartridge slot). Video time frame is 1:05 until 2:07. I'm really doing it step by step, but I get these weird Mesh artefacts when trying to move the face along the Z-axis.

See this picture:

Weird mesh artefacts

I also recorded the action on my screen:

I would be sooo grateful, If someone knows what I did wrong, or which details I missed along this process. So far I really like this tutorial and I learned a lot. :)

  • Martin Bergwerf replied

    Hi Josua,

    You need to Extrude, before pulling that part down. Watch that section of the tutorial again and pay close attention...

    (You're not the first one to make this mistake...)

    1 love
  • Omar Domenech replied

    Ah I see what happened there. You moved the faces without first extruding them and you dragged the attached faces with everything. If you notice in the video, at the bottom where it shows the keyboard keys JL is pressing, when he selects that part there is an E, so he is extruding first, which creates new faces and then he moves it down.

    1 love
  • Josua Morgalla(JosuaM_92) replied

    Ha, I feel kind of embarrassed ^^. but to be fair, in the video the tutor just said to move the selected face along the z-Axis...it was just the Keystrokes recording in the viewport that showed that he really did extrude the face before moving it down along the z-axis.

    Anyway, thanks again for your quick feedback. Now, I can finally do more happy blending :D