Stailess Steel rudder?

[BertKu]

Originally Posted by lewisboats

until you remove the ready oxygen from the surface. The chromium needs a steady supply of oxy to create the film of Oxided chromium which protects the substrate from corrosion. The whole reason the barnacles promoted the pit corrosion is because they sealed the surface away from oxygen. Your coating would suffer the same result...and why would you paint Stainless steel with stainless steel?

Hi Lewisboat and Mercury,

Have I understood you both correctly, should hardagoo and I, make a ss 316L rudder and have it powdercoated with a nice white paint, if the boat is also a nice white colour, I will have problems at a later stage, because I seal the surface of the SS316L and the chromium can't breath. Good that I read this thread, I would have blindly gone through the expenses and had it powdercoated. Thank you so much for the information provided.
Bert

[Mercury]

Hello all,

I found the link on Youtube please see
http://www.youtube.com/watch?v=j1SZT2xcuuY

I think you will get a better idea than I can describe in written form. Please note the coating had not been polished in any way, was simply coated and placed in the water where it remained for slightly over ten months. had the coating been polished to say a satin finish the result would have been the same (no corrosion).

Hope the above link helps.

Originally Posted by Mercury

... Please note the coating had not been polished in any way, .....

Hope the above link helps.

No, sorry it cannot help. The question was to replace a GRP rudder with a SS made one. In this case every coating is nonsense and leads to crevice corrosion.

Leave it!

[Mercury]

Dear Ms/Mr. leave it.

If you took the time to read the thread the question was posed to me directly about the potential of reducing the weight of existing Stainless steel rudders, each weighing 60 LBS. My reference was to perhaps replace the SS rudders with a lighter weight substrate and if still wanting to have the appearance of SS then it could be coated with what has been proven to work for many years, with zero crevice corrosion. It is used on Ocean going tankers for at least ten years. So, I suggest before climbing all over someone who was asked for advice and gave it humbly, you take the time to read.

I will not post again as this type of BS is not worth my time.

Enjoy!

Originally Posted by Mercury

I will not post again as this type of BS is not worth my time.

Nice!

...at least you have choosen the right board name

And you have NOT being asked to post that nonsense as a reply on the original question:

Originally Posted by Mercury

Hi,

I was on some time ago discussing a new Stainless steel spray product, requires no heat, can be sprayed on or rollered. Product consists of 316L SS powder and a proprietary polyester binder. Possible to spray in almost any configuration, is extremely abrasion resistant and is used to protect the leading edges on wind turbine blades and airplane propellers. The company supplying this product is based in Temecula California. if interested I would be happy to pass on more details but do not wish to use this forum to promote any particular product.
Terry

all clear?

leave it!

[lewisboats]

I'm a metal fabricator -- machining and welding. Its recently happened that my rudder has started to delaminate and I'm gonna need a new one. For my boat, I've been quoted $1700 cdn for a new rudder with a foam core.

What I'm wondering about is why don't people just fabricate a stainless steel rudder made from:

-- Stainless Steel rudder stock.
-- 316 stainless steel sheet folded over rudder stock and welded and re-inforced in places....


...The weight of the rudder would be even less than my current rudder. My current rudder weighs in at 150 lbs (I'm thinking it might be because its soaked with water??)

Mercury...if you re-read the original post...he was asking about making a Stainless steel rudder which would weigh less than the laminated one he has now which weighs 150 lbs. A hollow Stainless rudder would weigh significantly less than that. No need to get into a beef with folks especially if you misunderstood the original poster's intent. I believe you mistook ChrisN67's post as the original...please go back and reread the OP.

[Mercury]

Thanks lewisboats for clarification. My intent was to indicate an alternate potential for keeping the look and properties of stainless steel while drastically reducing weight. I am attaching (hope it works) images of a rudder from a two racing yachts which were coated with SS 316L and then polished. The original rudders were fiberglass and was prepped just the same as one would prep for paint. The SS was sprayed on using an automotive spray gun and added approx. 50 grams per sq foot of weight when complete. The owners of the vessels have stated they are enjoying great success with maneuvering in light winds.