inox / silicon bronze screws
 

I'd like to know what the main differences are between inox screws and
silicon bronze screws (in boatbuilding). Vantages and disadvantages. I ask
this question, because it's easy to find inox items here in my town, while
there is no choice of silicon bronze screws

thanks

"pietro" ha scritto nel messaggio

inox screws

sorry, I mean: stainless stell

Generally, stainless steel screws should only used above the waterline.

Bronze can be used above or below the waterline.
There is more information in the notes at the bottom of this page:
http://www.jamestowndistributors.com/ak/Fasteners/

"pietro" wrote in message
...
"pietro" ha scritto nel messaggio

inox screws

sorry, I mean: stainless stell


Stainless steel is only stainless if there is oxygen present.
Below the waterline, stainless becomes much like swiss cheese... Called
crevice corrosion.
Stainless also comes in different grades... the more expensive of which is
better resistant to crevice corrosion..and can be used for things like
rudder fittings where the water is disturbed/turbulated a lot and thus a
little oxvegen gets to the fitting...
But i bet the stainless that is available locally is NOT the higher grade
stuff.

You spent how long and how much on the boat?
The percentage of the total cost in time and materiels that the screws
represent?
It is seldom worth skimping on the screws...... sorry.

thanks to everybody!

I’d like to repair a quite wrecked wooden boat (I got her as a present);
many screws were missed along the keel; the boat is for recreational
activities; I’m living in countryside and therefore I’ll have to tow her
with my car to the see; I don’t intend to leave her in the water all the
time; I’m looking for an arrangement; what about brass screws?

....or : to fasten the lap to the keel, is it possible to use copper nail NOT
rivetted but simply nailed into the keel? maybe with a bit of epoxy glue (I
mean: drilling the keel and gluing the nail in the hole)? please don’t be
shocked, I’m a woodworker (hobbyist), not boatbuilder

On Tue, 01 Mar 2005 14:56:49 GMT, "pietro" wrote:

I'd like to know what the main differences are between inox screws and
silicon bronze screws (in boatbuilding). Vantages and disadvantages. I ask
this question, because it's easy to find inox items here in my town, while
there is no choice of silicon bronze screws

thanks


Silicon bronze screws won't rust - ever.
Their initial strength is lower, usually.

Brian Whatcott Altus OK

On Wed, 02 Mar 2005 10:21:49 +0000, pietro wrote:

thanks to everybody!

I’d like to repair a quite wrecked wooden boat (I got her as a present);
many screws were missed along the keel; the boat is for recreational
activities; I’m living in countryside and therefore I’ll have to tow her
with my car to the see; I don’t intend to leave her in the water all the
time; I’m looking for an arrangement; what about brass screws?

Never use brass on a boat.

Brass has zinc and copper in it. These two react in the presence of an
electrolyte (e.g., salt water or even moist salty air) turning the zinc
into zinc oxide (a structurally weak white powder) with copper around it.
Overall this weakens the brass so badly that it will just about fall apart.

Nickel plated zinc is another material that should never be used on a
boat, for similar reasons. For some reason, a lot of cheap boats use
nickel plated zinc fittings.

--Mac