Questions answered: the rope is Paracord. It seems to have all the strength needed.
The drill:. Pretty sure it was a 7/16. The dowels were a light tap with a hammer fit. On other forms that weren't a tighter fit I have put a drop or two of titebond on them.
Hmmmm, I didn't do any shims anywhere. You might be looking at my cobbled up side guides? I guess that would be a shim. There are two on each side in the area of the riser to make sure it stays straight. Those guides are the same ones I used for the rubber band system except I shortened them and rounded them off. These would be better made of metal for sure.
So, I'm calling this a success. The glue lines are good everywhere. These are pretty steep. They rise from zero to 1.75" over a length of five inches. The glass and a .030 parralel are all that runs up the belly side of the riser. I have previously built with thick butted tapers running up the ramps and know that they can be problematic with any pressure system unless it is perfect.
For a pressure strip I used a full length strip of galvanized sheet metal gotten from Bingham 26 year ago.
The zip ties are ideal for this process. I pulled them very tight and was able to position the side shims perfectly when the ties were pulled tight and was able to wrap the hose down without anything skittering around.
I put ten pounds of pressure on hose and cut and pulled the ties. I overlooked one which my sharp eyed grandson spotted after airing to 75# and we were able to cut and pull it but I suggest pulling them at low pressure!
Here's some pictures.
Some things learned.
The dowels are 2.5" apart. A bit closer together would probably be better.
You need to get ALL the air out of the hose.
You need to keep the hose carefully centered and not allow it to extend more over either side.
You need to pull the hose down tight against the layup. You are simulating a top form with a minimal gap.
So that's it for now. Happy to answer any questions and hear all suggestions.