"Stephen Mitchell" wrote
There is nothing wrong with the Zenair approach ... it is used on the
CH-2000 and thus has been certificated by the FAA ... the method is however
a little unusual and can be a little confusing for some builders. I am not
quite sure why Heintz uses this method in lieu of a more standard
installation. Perhaps someone can enlighten us.

Actually, he makes no secret of it and discussed it at a seminar at
Oshkosh. With any luck, I remember this correctly, so here goes:

He opted for mechanical rivets because they can be set by one person,
and without the noise of a rivet gun. Basically, this is so married
builders can keep peace in the household. Given the domestic
situation of most pilots/builders, I can see his point.

Given that he was going for mechanical rivets, the next question is
which ones. He did not opt for Cherry/CherryMax solely because of
cost; they are a good rivet and has structural properties such that
significantly fewer rivets could be used. However, the overall cost
would have been higher. He decided not to go with the commercial
(POP) rivet because the round head did not lead to a consistent
installation, so while the individual rivets are substantially
cheaper, he would have had to design in a lot more of them. He opted
for Avex rivets because the mushroom-shaped head yielded a reasonably
consistent installation and the cost was reasonable.

In fact, Avex rivets were originally designed for aircraft use and are
used in some certified aircraft. However, the approval process took
too long, and meanwhile they found a market in consumer goods. In the
end, that turned out to be the lucrative market, and aviation was
abandoned. Hooray for certification...

Michael