Glen-L.com

Reading through many of the posts here, I'm finding just as many opinions. So....can stainless screws and/or ring shank nails be used as a reasonable substitute for silicon bronze???. Since many fasteners are removed anyways, I would think this would avoid any risks that stainless may or may not cause is the long run (ie. rusting out from the inside, deteriorating in the absence of O2 in the case of encapsulation..etc, etc). One of the only problems that I see consistently through the majority of the postings is the brittle nature of stainless.

Thanks, Chris

I'm not getting into this one ,but to clarify one thing: the ring shank nails you use are bronze & you CAN'T remove them after they are driven in place....the heads have pulled off when I tried.

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Boat building can best be defined as an endless series of
tragedies obscured by the occasional miracle, followed by a good bottle of beer.

Don't Dream Your Life, Live Your Dream

I understand that about the nails. I have no intention to remove them. I was just lumping them in with my other question about stainless vs silicon bronze.

Thanks, Chris

Do not think that stainless steel fasteners are brittle.
Stainless by nature is a soft and gummy material.
This is why it is not the easiest material to machine.

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If you don't build it now, You will regret it later!

Crackerbox Build:
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It's a no brainer, stainless is only good as stainless when it is exposed to the
air. I can't go into the science of it but once it is in an airless environment it loses its stainless property and can rust.

Oh man, now I'm really confused. I thought that for an iron based metal to rust, it had to come into contact with water AND oxygen. So in order to inhibit this process, one would try and inhibit the reaction of the iron to either air or moisture. I'm rambling a little here but bear with me.

Since we can't guarrantee that our iron based metal will always be used in an environment free of air and moisture, we would start creating alloys that would inhibit the reactions that would start the rust cycle. The way we do this is by injecting chromium into the mix. ....hence stainless steel. Now I fully understand that stainless steel can rust given the right circumstances, but it IS resitant to rust because of the chromium. Also, doesn't stainless steel develop a "passivation" layer that would hinder further oxidation? Ergo, it LOOKS like it's rusting when in fact, it only develops the appearance of rust on the outside?

Seriously, I'm just asking here NOT arguing. I really don't know.

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Isn't it amazing!! The person that never has the fortitude to pursue his own dreams, will be the first to try and discourage you from pursuing yours.

Dave,

I don't know either,but on my last TNT build in 1985,before the forum & I didn't know any better,I used stainless on my build.

The boat was encapsulated,& used in saltwater most of it's life.

I never noticed any evidence of rusting of the screws(bulging,or stains,etc),but if they disintegrated,the epoxy did a great job of holding the boat together anyway.

I only gave the boat away after I discovered rot in the bottom ply near the transom& in the transom itself due to letting the boat sit uncovered outside with rainwater in it & the transom top exposed.

I never saw any problem with the stainless fasteners though(and I'm not saying there wasn't a problem there,just saying no evidence)

Believe me I kicked my own butt for being a neglectful jerk on this!!!

_________________
Boat building can best be defined as an endless series of
tragedies obscured by the occasional miracle, followed by a good bottle of beer.

Don't Dream Your Life, Live Your Dream

In basic 300 series stainless steel does not rust. (Low carbon content)
400 series stainless is a commercial grade and a higher
content of carbon. If left in constant contact with moisture
it will show signs of rusting. If wiped dry it will rsist rust.

Until joining this forum I had never heard of stainless oxidizing
in a oxygen free environment. It was always my understanding
that it was the introduction of oxygen which contains moisture that
causes the oxidation.

I will have to go back into my metallurgy books and see if I can find more info. Interesting situation!

_________________
If you don't build it now, You will regret it later!

Crackerbox Build:
http://s232.photobucket.com/albums/ee255/jtpatronimfg/

Stainless is affected by Chlorides (salt) and will corrode. A304 is more subject to chloride corrosion and A316. Stainless is very close to aluminum galvanically. It will go away faster than carbon steel in a salt environment with steel.

Scary isn't it!

Bill

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Mini -Tug, KH Tahoe 19 & Bartender 24 - There can be no miracle recoveries without first screwing up.
Tahoe 19 Build

That is very interesting info Bill. I was a damage controlman in the Coast Guard and we used quite a bit of 304 on exterior parts of the ship.
All the water tight hatch combings were fabed from formed 304 angle.

Is this info that has been recognized in the last 25 years or so?

_________________
If you don't build it now, You will regret it later!

Crackerbox Build:
http://s232.photobucket.com/albums/ee255/jtpatronimfg/

The A304 vs A316 definitely has been around. A big difference maybe keeping it washed down. Part of my preference may be shiny stuff with A304 more prone to surface pitting.

On nuclear plants we had problems with Inter Granular Corrosion Stress Cracking . Which is chloride corrosion slightly internal to the metal. It effectively pries the metal apart. But, this was a very high temperature and pressure environment.

I am on the very edge of my experience and knowledge. There are no guarantees or warranties implied.

Bill

_________________
Mini -Tug, KH Tahoe 19 & Bartender 24 - There can be no miracle recoveries without first screwing up.
Tahoe 19 Build

Bill

Where does 316L fit into the picture?

Carl

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Carl
If not now......When?
http://s270.photobucket.com/albums/jj94/gashog7/boat/
http://www.epoxyworks.com/26/index.html Number26

Carl,

A316L is low something (magnesiun,...,...,...). Hell, I don't remember. It is actually a little better in a chloride environment than A316.

But, I'm not supposed to know any of this stuff.

Bill

_________________
Mini -Tug, KH Tahoe 19 & Bartender 24 - There can be no miracle recoveries without first screwing up.
Tahoe 19 Build

Somebody out there probably needs a link right about now

I'll offer up a link to Mark Bronkalla's article in WebLetter 32 :

Stainless steel fasteners

More links at the end of his article . . .
__________________
Paul Kane Chelsea, PQ

Building the Glen-L Hot Rod : http://www.boats.chelseacoachworks.com

What about brass?