(1) The purpose of my sandblasting reply was just to provide the originator with a picture of what a prep-sanded area looks like when sanded by hand. Not to slight Burt or the plans, it is nearly impossible to sand the valleys completely dull. If you watch the Rutan composites video, you will see that not even Burt achieved a totally sheen-free prep sand. My picture looks alot like the one in the video.
(2) In my opinion, sandblasting is not practical for prep sanding for follow-on, structural layups. Too much mess for so little gain.
(3) Was said, "For the areas that Burt has designated as critical structure, you want to make sure to use peel ply well (no gaps where it doesn't touch) and avoid the sanding." I don't agree. The peel ply is to keep layups from delaminating from the edges. At least it says so in my Cozy Chapter 3 education chapter, that is as far as I know an exact duplicate of the Long-EZ plans with the exception that the "CP" bucaneer has been whited out and relabled as the "CZ" bucaneer. The Rutan video backs this up too. The education chapter says to prep sand with larger grit sandpaper. The video uses 36-grit to prep sand a non-peel-plied area. And no, peel ply doesn't mean "don't have to sand." There are alot of experts in the field that say you MUST prep sand peel-plied areas before applying the next structural layup. There is at least one presentation on Marc's website that tells the reasons why.
(4) Was said, "In my microscopic mind's eye, I see millions of tiny stress concentrators (crack starters), each on a grain of sand or whaterver, where we might not want them. If, however a structural bond is weaker because of media inclusions, the result may be more catastrophic." My answer--> Total BS. Don't knock it until you try it.