Received-SPF: pass
 receiver=logan.com; client-ip=209.85.216.180; envelope-from=david.staten@gmail.com
DomainKey-Signature: a=rsa-sha1; c=nofws;
        d=gmail.com; s=gamma;
        h=message-id:date:from:user-agent:mime-version:to:subject:references
         :in-reply-to:content-type:content-transfer-encoding;
        b=v83HEKkufk+Ds+TjafDKnWvu1ulJEbUlvqaU2msWBqeKMzRN9SdOgQMsN5Ayx8tLT2
         +vJNnyBYXCGhBoIDwtUQ934/Nr3lkCIkvruSdSIRDEqbo3MM49XTDiSQ4XsW5uGGICZM
         l/E/YGOldi+NyjPpxTJkDQMEs2Xfp/zcYcLNo=
Message-ID: <4C43928A.60204@gmail.com>
Date: Sun, 18 Jul 2010 18:47:22 -0500
From: Dave <david.staten@gmail.com>
User-Agent: Thunderbird 2.0.0.24 (Windows/20100228)
MIME-Version: 1.0
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Subject: Re: [FlyRotary] Re: Tie Down Hardpoints
References: <list-4397670@logan.com>
In-Reply-To: <list-4397670@logan.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit

Up until a few minutes ago I was incredulous that this could be the case.

While wikipedia is not authoritative (no guarantee the source is 
accurate) it does substantiate what you say you read.
http://en.wikipedia.org/wiki/Stainless_steel

Thomas Mann wrote:
> Yeah ... I just know what I read.
>
> Here is the explanation I read:
>
> "The basic resistance of stainless steel occurs because of its ability 
> to form a protective coating on the metal surface. This coating is a 
> "passive" film which resists further "oxidation" or rusting. The 
> formation of this film is instantaneous in an oxidizing atmosphere 
> such as air, water, or other fluids that contain oxygen. Once the 
> layer has formed, we say that the metal has become "passivated" and 
> the oxidation or "rusting" rate will slow down to less than 0.002" per 
> year (0,05 mm. per year).
>
> Unlike aluminum or silver this passive film is invisible in stainless 
> steel. It's created when oxygen combines with the chrome in the 
> stainless to form chrome oxide which is more commonly called 
> "ceramic". This protective oxide or ceramic coating is common to most 
> corrosion resistant materials."
>
> ------------------------------------------------------------------------
> *From*: "George Lendich" <lendich@aanet.com.au>
> *Sent*: Sunday, July 18, 2010 5:17 PM
> *To*: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
> *Subject*: [FlyRotary] Re: Tie Down Hardpoints
>
> * *Thomas,
> Well that's a new one on me.  Sound to me you might be getting 
> confused with Anodized Aluminium. I know lower grade stainless can pit 
> because of electrolysis in extreme environments and because of that 
> they use 316 ( marine) grade. I know carbon grade stainless can rust
> However if anyone can confirm this I would appreciate hearing 
> further about it.
> George ( down under)
>
>     I think I want to stay away from the stainless because it will be
>     completely enclosed in fiberglas.
>     Stainless needs to be exposed to an oxygen environment in order to
>     for that protective layer (chrome oxide) that prevents further
>     oxidation.
>
>     At least that's what I've been told/read.
>
>     ------------------------------------------------------------------------
>
>      Thomas,
>     I agree with Tony, use something that won't rust, nothing looks
>     worse on the exterior of a plane. Maybe consider stainless steel,
>     I use it on everything.
>     George (down under)
>
>         Hey Tony.
>         Now I'm looking for the tie down hardpoints (either parts or
>         specs) referenced on page 25 of the 'A' kit manual.
>
>         I have not found them in the drawings either.
>
>         They say thay are Cad plated steel. I can have them made but I
>         would be guessing.
>         Maybe .125  3" x 3.5" plate would suffice with a threaded
>         steel bushing welded to it and then plated.
>         I figure the bushing threaded/tapped 1/4" x 28 could be 5/8"
>         material ... maybe. ... or 3/4".
>
>         Any Ideas?
>
>         Thanks.
>
>         T Mann 
>
>
>