SS screws and exterior plywood

SS screws and exterior plywood

Post by habb » Mon, 31 May 2004 22:01:57


4 years ago I built a 22' center console, plywood / epoxy and during the
construction I asked a lot of questions here. Anyway one of the questions
was whether to use SS screws or silicon bronze. A lot of people said the SS
would develop crevice corrosion. I am doing some repairs and have taken out
a lot of the screws out of the bottom that were sealed under epoxy. This
boat has spent about 5 months of every year in salt water since 2000. The
screws I removed look identical to brand new screws now. Also the boat was
entirely made from hardware store fir plywood rather than marine plywood
which many also insisted on. No problems yet. I am not trying to convince
anyone of anything but if someone wants to build a boat on a tight budget
there is no reason not to use SS screws and exterior plywood as long as they
use epoxy /cloth with it.
 
 
 

SS screws and exterior plywood

Post by Steve Lusard » Tue, 01 Jun 2004 00:06:07

That is understandable. In order for crevise corrosion to be a problem, the
fasteners have to be wet.
Steve


Quote:
> 4 years ago I built a 22' center console, plywood / epoxy and during the
> construction I asked a lot of questions here. Anyway one of the questions
> was whether to use SS screws or silicon bronze. A lot of people said the
SS
> would develop crevice corrosion. I am doing some repairs and have taken
out
> a lot of the screws out of the bottom that were sealed under epoxy. This
> boat has spent about 5 months of every year in salt water since 2000. The
> screws I removed look identical to brand new screws now. Also the boat was
> entirely made from hardware store fir plywood rather than marine plywood
> which many also insisted on. No problems yet. I am not trying to convince
> anyone of anything but if someone wants to build a boat on a tight budget
> there is no reason not to use SS screws and exterior plywood as long as
they
> use epoxy /cloth with it.


 
 
 

SS screws and exterior plywood

Post by Jame » Tue, 01 Jun 2004 02:36:59

5 months of the year is simply part time.
crevice corrosion.occours in stainless when it is wet and there is no oxygen
presernt.
You are right about using stainless when the buget is tight... but with some
caution and regard for the use
7 months not in the water makes a huge difference.


Quote:
> 4 years ago I built a 22' center console, plywood / epoxy and during the
> construction I asked a lot of questions here. Anyway one of the questions
> was whether to use SS screws or silicon bronze. A lot of people said the
SS
> would develop crevice corrosion. I am doing some repairs and have taken
out
> a lot of the screws out of the bottom that were sealed under epoxy. This
> boat has spent about 5 months of every year in salt water since 2000. The
> screws I removed look identical to brand new screws now. Also the boat was
> entirely made from hardware store fir plywood rather than marine plywood
> which many also insisted on. No problems yet. I am not trying to convince
> anyone of anything but if someone wants to build a boat on a tight budget
> there is no reason not to use SS screws and exterior plywood as long as
they
> use epoxy /cloth with it.