You saw the block in its state post machine work, here's how the rest of the project went.
After sewing down all the triangles.
You can't see it in this view, but I left one edge of the cube open, for stuffing and for ease of manuevering with the hand-sewing.
This is what it looked like once I started pinning and stitching down the window panes.
Ready for stuffing!
Stuffed and ready for stitching.
I closed up that opening with a running stitch and then put the last window pane in. Through the process, I realized that it might have not been too difficult to have done all the initial machine joins but one, stuffed the cube, and then machine-stitched the last opening closed. Doing the hand stitching on the stuffed cube wouldn't have been quite as easy as on the unstuffed cube, but it wouldn't have been that much extra effort.
The finished product!
So it's actually quite big for a pincushion. And I do worry that going through so many layers of fabric will dull the straight pins. I might end up using it as a 'thing' purely for decoration rather than as a pincushion, but we'll see. Mainly, I wanted to see how a cathedral window cube would go. I like it. Sometimes success is easy!