For a lot of us, separating a piece from a mesh for a kitbash feels like expert territory, something to skip or hand to someone fluent in a modeling suite. What makes this stand out is how small the workflow is. The cutting is carried out by a single Boolean Difference operation inside Blender, and the method is described as needing almost no Blender knowledge. First uploaded tutorial or not, that pitch makes mesh editing feel reachable for anyone who prints minis.
The steps themselves are tight. Shift plus A opens the Add menu and drops in a cube mesh. The cube gets moved and scaled until it fully encloses the backpack area that has to go. Then the bust is selected, a Boolean modifier is added through Modifier Properties, the operation is set to Difference, and the eyedropper picks the cube as the target object. Apply the modifier, drag the cube away, and the backpack comes off cleanly, leaving a flat cut surface ready for export.
The demo model is a miniature bust of a sci-fi desert soldier, and using a plain scaled cube as the cutter seems a smart call to me. Nothing has to be authored first; you just position and size it.
The one open thread is that this covers a single cut on a single bust. Combining models for conversions is the natural follow-up, and the maker has said that suggestion is going on their content list.
Project by iPaintSmallThings. Watch it on their YouTube channel: