Hitting the goal for the blueprints isn't that impressive. Their target was $3,000. That's only a hundred copies of the blueprints with no other premiums. At the moment, there are 117 backers, with 73 pledging the minimum just for the blueprints, 10 getting the blueprints and 4 stickers, 27 going for the blueprints, stickers, and a set of patches, and 3 people pledging at the $400 names-in-credits level. Interestingly, usually there's a limit for something like that, but there isn't one here, so it'd be possible (thought stupid on multiple levels) for dozens of people to pledge at that level, so that the cover is filled with the names of randos in teeny, tiny type.
But, anyway, my point is that 100 copies at $30 a pop of even a niche product like this isn't that many.