Robin wrote:

Hello Paul,

    I hope this doesn't immediately sound like a dumb question, but how

can you find out exactly what the particular specifications for any given
"AN" part is?  For instance:  Metallurgist typically say there is just about
no difference between an American made grade 8 bolt and an AN bolt.  Well,
that's fine and dandy and we all can see that relationship pretty well when
you're talking about common fasteners,  but what happens when you begin to
talk about other products?  How can you really make a sound comparison?

    Let's face it, we're building experimental airplanes and we do a lot

of things that wouldn't make muster for what we consider "AN" standards.
Nothing points this out more than the fact most of us on this forum are
working with rotary conversions.  Having said that, we all are trying to
build the safest airplane at the lowest possible cost too, so how do we get
the truth about the real differences between properties of different
products?

    Collectively, we believe the rotary is superior to the Lycoming, and

we can prove it a dozen different ways.  It's when we begin to get into the
auxiliary systems that we always get into trouble.  Perhaps it's the way
we're thinking Paul.  If we can find superior engines to Lycoming, then why
isn't it just as probable that we might find superior "other" parts for our
installations?  The trouble is we don't have a good way to realistically
compare most of them.  Methods and materials are changing so fast we really
need some credible way to compare apples and oranges so we know which one to
put in the salad.  Some of the new stuff might actually turn out being safer
than the old tried and true AN product, but I'd prefer to find out about it
on the ground rather than in the air.  Unfortunately, it's likely to be we
experimental guys who find out first, one way or the other.  --  What are
your thoughts on how to compare apples and oranges in an evolving
environment?

Robin

Ian & Irene Beadle wrote:

A grade 8 bolt, the same as an ordinary AN bolt! I don't think so. A mild
steel bolt with rolled thread to close tolerance cad. plated maybe, but high
tensile grade 8!
Ian . Western Australia.

 
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