Revision A of Luggable PC Mark II is a bare-bones skeleton that proved that all the components can more-or-less play nice together. It did not try to do anything beyond that, such as actually being a luggable chassis. That’s the job of future revisions starting with revision B.
Up front and center is to find a way to attach a carrying handle. Rev A had two load-carrying extrusion beams sticking up straight through everything, which was easy to build but got in the way of packaging components around it. For rev. B I wanted to try routing all the structural extrusions around the outside of the enclosure.
When building Luggable PC Mark I I had designed the frame with all the extrusions precisely seated against each other. This turned out to be a mistake because it was very difficult to cut beams to exact lengths and also to have exactly squared-off ends. The edges of the extrusions are dependably precise: the same could not be said of the ends.
Applying that valuable lesson to Mark II meant that all the extrusion-to-extrusion contacts are edge-to-edge. The ends of the extrusions will either go into 3D printed plastic or just dangle into space. This way, minor error in length and squareness will not affect the overall design.
Misumi does not sell ready-made brackets to bolt 15mm HFS3 extrusions together, so I designed and 3D-printed my own. Since I’m making my own custom designs anyway, it was easy to incorporate features I wanted in my own design. In the case of the exterior frame of rev. B, it meant shock-absorption bumpers for the corners of the frame.
PLA is not very flexible so the impact absorption will be minimal, but it was fun to build.