[PSUBS-MAILIST] Stainless prop shaft

[Rick Patton via Personal_Submersibles]

316-L is about as good as it gets but also reflected in it's price. Also 
make sure you use a stainless steel wire wheel or hand brush and a 
grinding disc that says aluminum on it if you need to grind it. You will 
impregnate the metal with bad stuff if you use a grinding disc for 
steel.:-(

Rick

On 1/9/2015 11:37 AM, Stephen Fordyce via Personal_Submersibles wrote:
> Hi Brian,
> SS304 is the most common grade of stainless for general use, but SS316 
> is the most common used in marine (and is usually what people mean 
> when they say "marine grade").  That said, the difference in 
> performance is mainly cosmetic for intermittent salt water use (ie. 
> some very light "tea-staining" rust), and I've used various bits of 
> SS304 on my boat and dive gear that are absolutely fine years later, 
> although it all gets fresh water washed after use.
>
> For continuous exposure to salt water, or with crevices (ie. your thru 
> hull seals) likely to trap and hold salt water, SS304 is likely to 
> eventually corrode enough that it may eventually wear or cause the 
> seals to develop leaks.
>
> I know at least sometimes the prop & propshaft on bigger boats is 
> protected from corrosion with an anode, which wouldn't be very 
> practical on a thru hull.  Possibly this explains why the one you have 
> is 304.
>
> Another thing I see at work all the time is contamination of any grade 
> of SS pipe with carbon steel dust from grinders, drill shavings, 
> etc.  A piece of SS you thought was clean left in the rain will 
> develop nasty rust spots overnight! Important to store your SS away 
> from carbon steel workshop areas and/or cover it.
>
> Cheers,
> Steve
>
> On Fri, Jan 9, 2015 at 7:59 AM, Brian Cox via Personal_Submersibles 
> <personal_submersibles at psubs.org 
> <mailto:personal_submersibles at psubs.org>> wrote:
>
>     Hi All,
>                  I was given a stainless steel prop shaft which is
>     about 1 1/2" in diameter, I have cut it up into 2" long pieces so
>     they can be used as thru hull fittings for some of my rotating
>     shafts that I will be using.  I was always under the impression
>     that the prop shafts were a highly resistant alloy of stainless
>     and would be good for my application.  I recently was able to have
>     someone do a spectral analysis of the metal and it showed that the
>     material is 304 stainless.  I'm wondering if that will be good
>     enough to use as a stainless fitting for a thru hull ?
>     Brian
>
>     _______________________________________________
>     Personal_Submersibles mailing list
>     Personal_Submersibles at psubs.org
>     <mailto:Personal_Submersibles at psubs.org>
>     http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>
>
>
>
> _______________________________________________
> Personal_Submersibles mailing list
> Personal_Submersibles at psubs.org
> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.whoweb.com/pipermail/personal_submersibles/attachments/20150109/a86698bf/attachment.html>