quick note: with the new "building skin fixes" update, the gap became a bit tighter, and the visual gap disappears when the bunker is sealed with HQM at the bottom and space on top. it still works, but its a bit harder to get the gap. For the roof one, nothing changed and it still works perfectly
with the new space station building skin coming in rust's december force wipe, you can make sealable HQM pixel gaps, both horizontal and vertical. this is insanely powerful tech, as it allows you to hide and seal away loot essentially anywhere.
the first method i show to create the wall-wall gaps was first showcased (afaik) by GameLightz:
• UNLOOTABLE PIXEL BUNKERS, the easy way! (A...
if you're curious about technical details of the vertical gaps:
-if the lower half wall is space station, essentially any gap can be reached through, however there aren't any reliable ways to create smaller gaps.
-it stops working at around 7millimeters, at which point the "sealed" version also becomes lootable
for the horizontal gaps, any gap size can be sealed, it can even seal through bear rug gaps, and somewhere up to 9cm.