Artemia Salina kindly confirmed my impressions about installing rivets,
while adding some additional pointers:

On Tue, 16 Dec 2003 01:22:41 -0500, Allan Adler wrote:

I think the following conclusion is valid but it would be reassuring for
someone to confirm it: If you want to install a rivet, you take a small piece
of iron rod and hit it with a hammer until all the ends protruding from the
hole are too big to go through the hole. If you want it to be able to pivot,
make sure from time to time that you can still move it. If you want it to be
rigid, keep hitting it until it won't pivot anymore.

You're right, except that I would recommend drilling two (or more) holes
adjacent to each other in a joint and riveting them if you want the joint
to be rigid. A second or third rivet will positively prevent the pieces from
pivoting. And as I say, (red) hot rivets will form an even more rigid joint
due to contraction when cooled.


I went back and took another look at the drawings on p.71 and p.75 of
Gingery's book. There are definitely places where two rivets are indicated,
making it clear that he wants those attachments to be rigid, while the rest
are single rivets, indicating that he wants those to be able to move. So,
that clarifies his intentions about what is supposed to move and what is not.

Even though the upright rail is allowed to move, there might be a reason,
falling under the category of "ingenious mechanisms", why the upright rail
can move away from the motor but not towards it. I half convinced myself
that this is so, but I still need to think about it. Maybe someone (MikeM?)
with first hand experience with the Gingery lathe can perhaps confirm or
reject that conclusion.

Getting back to how one actually installs rivets, there are some more details
that I don't understand. First, how does one make sure that the rivet deforms
and doesn't instead move through the hole when one hits it with the hammer?
Presumably, some kind of support is required under the plate and/or rivet,
but what kind? Second, it seems that there might be some risk of causing some
deformation of the plate itself in the process of hammering on the rivet? Is
that risk real and if so how does one avoid it (this might be another reason
to prefer red hot rivets)?

Ignorantly,
Allan Adler


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