D4 Trapezium Design Notebook:  each design is a flurry of ideas and concepts merging into one--I try to keep track of the process with notebooks specific to each design.  Here is the D4 Trapezium Design Notebook, the second D4 design after the full size ledge was produced funded by the successful Kickstarter.

D4 Trapezium Home Build Wiki:

Frame kits and D4 Joiners available from BigWallGear.com email deuce4@bigwalls.net

Trapezium Design Notebook: https://www.bigwallgear.com/d4-trapezium-design-notebook.html

Anna's tips on sewing steps: https://deuce4.net/AnnaOctapodTrapeziumNotes.pdf

Patterns and tips also posted on bigwallsforum.com

Frame parts and dxf files (patterns in inches, DXF file available upon request):