Hey Matt,

First off I would ask you, mainly because I am really not familiar with
the rivets that you are speaking of. Primarily all of the aircraft
rivets previously and in use today all had the "AN" prefix to their
respective designators. Such as AN426, AN427, AN470 and so forth.
Additionally, some rivets had other designators to signify if the
material used in their manufacture were of something other than aluminum
alloys. Such as "C" for Copper, "M" for monel, "A" for what is reffered
to as a "Dead Soft" or pure aluminum (1100 series), "AD", "DD", "D", and
"B" (which is a magnesium rivet) and so forth, for the other types of
rivets which were in use. the Part number would look something like this
for a hard(er) aluminum rivet. AN470DD5-6. The desigantors you speak of
here, "S" and "ST" are old designators for aluminum sheet stock, such as
24S or 24ST. Although it is possible that those "S" and "ST" designators
were used on rivets I am not familiar with them or their respective use.
The "S" and "ST" desigantors used on the sheet stock were indicators
of aluminum temper "S" being annealed and "ST" being heat treated
hardened sheet stock. Before and during WW II there were many other
styles of rivets for aircraft. Flat Head, Round Head, Pan Head,
etc...but those gave way to what we use now in the "Universal Head",
which is the AN470 series. I would have to do some digging into my old
books to find you some more info on specific AN series of rivets. Hope
this helps. By the way...what year is the A/C that you are working on ?
I have worked A/C stuctures on and off, as has my father, for many
years. If I can help...shoot me a note at my e-mail adress.

Regards,

Paul

Matt wrote:
Hi all,
A slightly unusual question to pose to you all. I was wondering if
anyone might know if the old A17 series (S and ST) solid rivets had a
more domed head on them than the current AN470/MS20470 series do?
Would be interested to hear any thoughts on this. Many thanks and have
a great weekend.

Cheers,
Matt