Stainless Steel Bolts and Nuts

[firstascent2002]

Just a quick post.
Have recently replaced the windows in my seal 22 and whilst I was at it, found that I also had to replace all 52 bolts and nuts as the previous owner had just cut the bolts flush which had ruined the thread on about 3/4 of them. 52 nuts, washers and bolts in blisterpacks from f4 in Bristol would have nearly killed me (cost more than the windows!!!) Anyone needing nuts bolts rivits screws etc should check out www.gtc-direct.com. Total price under £4. I ended up getting all the other bits I'm going to need during the refit as if you top £35 then there is no P&P. Oh and one last thing. The actual price was lower than the catologue price as everything is rounded up to the nearest pence in the catalogue but not on the final invoice. I really love a bargin.

<hr width=100% size=1>

 

[Mike2822425]

Interesting, but check out if they are A2 or A4 Screwfix also do good deals on stainless.

<hr width=100% size=1>

 

[firstascent2002]

Yup they are A4. In the catalogue they do offer a2 which are even cheaper and say that you might get away with using them above the waterline...haven't used too many screws below the waterline myself...don't like making that kind of hole...

<hr width=100% size=1>

 

[Evadne]

For mail order check out <A target="_blank" HREF=http://www.a2a4.co.uk/>A2A4 fasteners </A> as well.

<hr width=100% size=1>

 

[Mike2822425]

Stainless is an interesting metal, (experts please come in at this point) it needs to "breath" to be effective (or does it have to naturally degrade to keep its properties). Paint it and it will degrade. If you ever have time wrap a piece of insulation tape round a tube and check in 12 months for corrosion. The area open to the air will be fine, but under the tape!!!





<hr width=100% size=1>

 

[Birdseye]

Yes, you are correct. Stainless needs oxygen to form the oxide film that protects the surface. So out in the open sea it works well, but bury it in wood or grp and it can corrode alarmingly. The difference between 304 (German A2) and 316 (German A4) is a percentage of molybdenum which simply makes the oxide coat tougher.

Stainless was discovered in the UK, and traditionally we have exported it all over the world including more to Sweden and Germany than they ever sent here. Half the steel for the worlds razor blades used to be (and might still be for all I know) made in Sheffield. So why we now use German nomenclature I do not know.


PS Aluminium also needs oxygen to maintain its surface protection. Without it, Al fizzes in water just like magnesium.


<hr width=100% size=1>this post is a personal opinion, and you should not base your actions on it.