I am noticing that the newer the gear the more the stainless steel seems to rust. Below are photos of 3 sail pulleys of the same brand and model, the 2010 has seen the most water time by far. I always wonder if the manufactures are cutting costs on purpose or their suppliers are just providing lower quality materials. You can see from the photos that the materials have also changed but it doesn't explain why 2012 has corroded more than 2011.
I have rust issues on some other pieces of stainless from other manufactures so I get the feeling it is probably happening across all brands. Anyone else noticing this?
Pretty sure the pulleys of the 2011 and 2012 are NOT steel at all, but more likely some brass/bronze.
Yeah it shows the use of cheaper materials over time. The brass or bronze could increase the rate of the stainless steel corrosion but the 2011 is fine regardless of this but the stainless on the 2012 has rusted badly.
316 is to be preferred but there is a lot of 304 about the place. 316 is more corrosion resistant. But none of its perfect, under certain conditions 316 will rust.
www.reliance-foundry.com/blog/304-vs-316-stainless-steel
A lot of the components are Nickel plated and not Stainless Steel at all.
Some are Stainless Steel (grades unknown) and can suffer corrosion for many reasons.
316 (marine grade) will corrode in salt water also under the right conditions.
Most of the rust is from contamination during the manufacturing process and coming into contact with steel tooling.
Simple Passivation can solve this problem but manufacturers don't really understand what they are doing.
All very basic stuff in an engineering environment but in water sport equipment manufacturing it is simply over looked
Boom adjustment clips are a good example.
Has anyone ever seen Hydrodynamix boom clip pins rusting & bursting out of the plastic
These days there are better materials available at a similar price to Stainless Steel but stronger & have better corrosion resistance.
Duplex & Super Duplex used to be very expensive but have come down considerably in the last 20 years.
A little harder to work with but out perform Stainless Steel of all grades as far as corrosion goes.
Passivation is still required though
If 2011 & 2012 are 316 then it looks like pretty bad "Tea Staining". This staining can be worse on rougher surfaces(Chinese machining) which would combine with the poor Chinese stainless to compound the problem!
My fabricator has broken teeth on his power saw when cutting Chinese steel due to hard impurities.
Select to expand quoteKimba said..
My fabricator has broken teeth on his power saw when cutting Chinese steel due to hard impurities.
Prob using a Chinese power saw..
Good morning, Init,
Nice post. My suggestion is that you name the sail maker and the model of sail in this forum. You might then lodge a complaint with the sail maker to see if they react.
You might also post the topic on the Boards (UK) forum:http://forums.boards.mpora.com/forumdisplay.php/5-Equipment?s=94fc22145906a81addd64a3c6978eea2
And the iWindsurf (USA) forum: www.iwindsurf.com/forums/viewforum.php?f=1&sid=8b185359fc2fe881d3e9f328c028e90e
To see if others are having the same problem.
Hi WindmanV,
Thanks for the reply. I don't feel the need to name the brand as I have never had any other issues and the gear has been very durable, if the Pulley breaks I will raise the issue then but there is every chance I will have destroyed the sail through other means before this happens. I just find it interesting that they have gone from all stainless to stainless and brass and then the quality of the stainless has reduced. I also don't have an issue with the brass pulleys unless they noticeably speed up the corrosion of the stainless. Functionally they are fine and is probably a valid way to reduce costs.
My post was prompted by the failure of some boom clips from another manufacturer that have rusted to failure. I just question if the manufactures have purposely chosen to use 304 instead of 316 stainless or if as suggested it is just poor quality 316 stainless and manufacturing.
I will raise it with the sail maker in case they are unaware but for all i know they may have corrected the issue in the last few years. I will also have a search of the other forums and see if others have raised similar problems.
Select to expand quoteinit9999 said..
Hi WindmanV,
My post was prompted by the failure of some boom clips from another manufacturer that have rusted to failure. I just question if the manufactures have purposely chosen to use 304 instead of 316 stainless or if as suggested it is just poor quality 316 stainless and manufacturing.
The Sail manufacturer would probably buy the pulley blocks from another manufacturer that specialises in manufacturing those types of items.
The pulley block manufacturer buys his bar stock in good faith probably specifying Grade 316 but what he actually gets could be anything.
He may also order a lower grade like 301 or 303 for easier machining or bending etc without even considering the end use as he has no idea wtf they are for.
In the Oil & Gas industry there has been a blanket ban on procuring materials from certain Asian countries for years as they are known to be dodgy.
Regardless of what the material certificate says they cannot be trusted to be correct.
I have had piping materials mechanically tested by Woodside & they passed but still rejected due to the country of origin.
Maybe some feedback to the sail, boom & component manufacturers will help to improve the quality but it's been going on for as long as I can remember
Surface finish plays a big part in tea staining and a bright finish 304 can give good or equal resistance to staining as 316 with a satin finish. I fitted my boat with some fittings made from 304 with the welds passivated and the electro polished with great results.
Most stainless out of Asia is of good quality these days and most likely better than what used to be made in Australia years ago but that last pic looks as if their has been some contamination from ferrous materials maybe in the production of the parts.
