AN Fittings

[Webb]

The AN schedule originates with aircraft grade hardware. Notice
that the first number is the shaft diameter in 1/16ths of an
inch. Then it will give the grip length (unthreaded portion of
the shaft) and the overall length, as well as whether or not it
is drilled for safety wire. It really is a simple system, and the
designation of the bolt, nut, washer, or fitting gives complete
information on it.

Normal hardware store bolts are referred to as "schedule 4" and
are made out of a material with a strength of about 70,000 psi
(from memory here). There is a better grade of hardware store
bolts called "schedule 8" with about double the strength.

AN bolts are the same strength as schedule 8 bolts, but the
threads are cold rolled instead of cut, and the corners are
rounded to eliminate "stress risers" (sharp corners are places
for cracks to start.) They are then plated with some sort of
super  corrosion inhibitor.

 The end result is a level of quality you'd want if it was
holding together your 1946 piper cub, when God tried to tear it
apart - again.

They aren't so expensive that you can't use'em just because it
makes you feel good!



Scott Croughwell wrote:

> This is a chart I received from the Talon Digest that some of
> you might find
> handy:
>
> AN Size         Metal Tube O.D.       Thread Size
> ~2                  1/8"                         5/16 - 24
> SAE
> ~3                  3/16                         3/8 - 24
> SAE
> ~4                  1/4                          7/16 - 20
> SAE
> ~5                  5/16                         1/2 - 20
> SAE
> ~6                  3/8                          9/16 - 18
> SAE
> ~8                  1/2                          3/4 - 16
> SAE
> ~10                 5/8                          7/8 - 14
> SAE
> ~12                 3/4                          1-1/16 - 12
> SAE
> ~16                 1"                           1-5/16 - 12
> SAE
> ~20                 1-1/4                        1-5/8 - 12
> SAE
> ~24                 1-1/2                        1-7/8 - 12
> SAE
> ~28                 1-3/4                        2-1/4 - 12
> SAE
> ~32                 2"                           2-1/2 - 12
> SAE
>
> And on another note, I did download the demo software from the
> Haltech
> website.  Does anyone have an ignition/fuel map they wouldn't
> mind emailing
> me?  (Or point me to?)  I'd like to see what a "real world" map
> looks like
> on that ECU, as I've never used one before.
>
> TIA!
>
> -Scott
> http://www.overboost.com