Stainless steel

[robertj]

Anyone know this?

Will an annode degrade faster if it's annode to hull bolt is stainless steel rather than galvanised steel bolt?

Bob

 

[coreng]

Galvanized bolt is a little more anodic than the zinc anode. Thus, consider inox bolt.

 

[VicS]

Anode fixing studs are usually zinc plated to give some protection against rusting when not in the water.
While the zinc plating is intact there is of course little potential difference between the studs and the anode but the plating probably does not last long so you then have mild steel and the zinc anode. Then there is a potential difference between them and some loss of anode material will be the result.
There is a much greater potential difference between stainless steel and zinc so it will lead to a greater loss of anode material.

However the exposed surface area of the fastenings is small compared with the surface area of the anode. This means that the rate of loss of anode material , even when using stainless fastenings, should not be a great issue.

There may be situations, a boat on a drying mooring perhaps where rusting of the fastenings in the air is sufficiently great to make the use of stainless fastenings attractive.

If I had anodes I would stick to the plated studs unless I found a good reason to use stainless.

 

[vyv_cox]

Nothing to add to Vic's post, he has it just right. Mild steel studs rust ashore and can look bad after a few years. No harm in painting them when you antifoul. Not the anode though!

 

[Bosun Higgs]

have tended to use stainless bolts to avoid the inevitable problems you get with rusty mild steel bots . Turning in the hull as you try to undo rusty nuts etc. replace every few years.

The erosion of the anode by using stainless or mild steel for that matter will be trivial, but in any case when did you last use up a whole anode as opposed to replacing half used?

So IMO theory says use galvanised mild steel but stainlkess is easier in real life.

 

[Ruffles]

There may be situations, a boat on a drying mooring perhaps where rusting of the fastenings in the air is sufficiently great to make the use of stainless fastenings attractive.

Mine rust inside the hull despite being well above the bilge. For that reason I'll probably replace them with stainless - assuming it's not ridiculously expensive.

 

[GrahamM376]

Anyone know this?

Will an annode degrade faster if it's annode to hull bolt is stainless steel rather than galvanised steel bolt?

Bob

Use standard plated mild steel studs, the fixing strap on half pear anodes is mild steel so best not to fix it with stainless bolts.

 

[KellysEye]

We have a steel boat and use welded stainless studs to attach the anodes. Never had any problems with that.