Hey Braytak....
Let me see if I can explain this for you.... First off, I used the Kirrou Hinged ODST Shoulders... Before even starting with the foam, i scaled them up to my size AND I built the paper pep file FIRST... to give me a idea of both how it would look and to give me a template to go by with the foam...ESPECIALLY on the center diamonds/pyramids....
So let's look at the design:
1. On most of the folds that are just simple mountains or valleys, I found that either 15 or 30 degrees works really well.... for most of these I cut the pieces out with a 90 degree edge first... then put pieces next to each other and figured out the angle... then go back to my bandsaw and just rip the angle on the edge (if you stay right on the edge you won't shorten the piece... just cut off the angle).
2. Where I wanted "flaired" out edges instead of incut edges, I decided on the edge angle first before cutting them... Most of those were 30 degrees....
3. The inset hole in the center, I cut with just a exacto knife... flipped the piece of foam and inset it and glued it... pretty simple....
Now things to consider.... In Kirrou's file, he talks about using a bolt or two to make the hinge... I did that... but honestly if I was to redo them, I wouldn't... I think I would figure out how to use black nylon shoe strings instead... thread them thru the diamond and tie behind the plate... My thinking... it will let the flaps move easily... and would also allow you to switch out the guard plates on the shoulder pads....maybe making custom plates... or allowing you to give the armor a different look with just a simple switch out...
Just a thought though....
I must say that a lot of mine was trial and error... just eyeballing and finding angles that worked for me... just take your time and work thru it slowly.... I did the top sections first and got those the way I wanted... then the two center diamonds... then lastly the cover flaps.... I porbably had... oh... 7 to 8 hours in both shoulder plates....
Hope this helps some!
Cujo3131