Without getting to into the science of retroreflective materials, they were essentially inspired by the reflective nature of cat eyes. Little prisms are cut into the surface of reflective material, which bounce a higher amount of incoming photons back at the light source. You know what I mean, you see it every day on the road.
So I thought why not use this for cycling? Maybe make a retroreflective messenger bag, or a retroreflective pack cover like the ones Respro UK makes (awesome company btw, cool products). After getting bag patterns and finding a heavy duty industrial sewing machine I was ready to make a bag, or so I thought. Luckily before I started I found out about VS Panels used in the military for all kinds of purposes. The story that I read was of a SEAL sniper using one to prevent one of our own Apache choppers from mowing them down. This got my attention, I thought about a simple ultralight hi viz panel that could be used in a multitude of situations. I realized I didn't want a hi viz bag, I wanted a low viz bag (or jacket) with the option to blend in, or be seen when necessary. The applications are really endless, from night running to backup safety when you're rear light battery dies, to temporary signage. Once you add stencils to the mix you've got a hi viz canvas to work with (something like <---- three feet to the left please) or (FREE.99 is one I always like too).
So I began sketching and cutting. After much iteration I've arrived at the design you see here.
1x Diamond Grade Retroreflective Vinyl Sheeting
2x Low Profile Quick Release Molle Clips
2x Double Sided Velcro
The Molle clips are great when securing to a belt or nylon webbing as you'll see later.
Step 1: The Pattern
I simply used sharpie on the back of the material and used a Xacto blade, the stuff is durable so it may take several passes with the blade, as always use care, you could easily use scissors too.