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USnavy
Dec 22, 2011, 11:00 AM
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bill123
Dec 22, 2011, 1:18 PM
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I thought SA bolts have corroded rapidly in a marine env.
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mattm
Dec 22, 2011, 5:31 PM
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Bolt Products passivates their bolts (I assume that's who you're referring too). Note that 316SS won't be that great in nasty marine environs. I'm betting you know that too though...
Bolt Products use Duplex SS in their marine bolts.
The Wave Bolts do look a bit rough when you get them compared to Titt bolts. I do a bit of cleaning up as well to help with corrosion resistance.
I'm working in smaller batches of 20 or so. I use Barkeeper's Friend (oxalic acid) to clean and passivate. I simply scrub them with a rough sponge with water and the Barkeeper's stuff. Polishes them right up. I've also used the stuff to clean up SS hangers that have rust stains on them from PS washers. They look like new when done.
If I were doing larger numbers of bolts, I'd look into running them all in a dishwasher with citric acid (look for dishwasher cleaner) Same idea. You still might need to do some spot scrubbing if there's real dirty spots.
Before
After
(This post was edited by mattm on Dec 23, 2011, 4:22 PM)
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tolman_paul
Dec 22, 2011, 5:51 PM
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Your best bet would be to tumble them in a polishing media.
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USnavy
Dec 23, 2011, 10:31 AM
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USnavy
Dec 23, 2011, 10:32 AM
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bill123
Dec 23, 2011, 1:38 PM
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Sorry. I meant SS (stainless )
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JimTitt
Dec 23, 2011, 9:23 PM
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We hand polish the exposed part of our 1.4462 bolts as the polishing smooths the surface and gives less chance of crevice corrosion than just passivating. The whole bolt is pasivated first.
We could electro-polish the whole bolt which solves the corrosion problems but the surface is smoother so less adhesion for the glue so we leave the rest of the bolt passivated.
Oxalic acid is o.k for cleaning rust but is not used for passivating to the AISI standards, only nitric/suphuric acid mixes and citric acid are listed as far as I can remember. Using nitric acid is pretty environmentally unacceptable in Europe as well as being an additional industrial hazard and is difficult to transport.
We use citric acid in conjunction with tumbling in wet ceramic abrasive as the acid is bio-degradeable, cheaper and safer. The chemical composition and ph value of the rinse water is important as well to promote rapid oxide formation.
The relative value of all the different treatments is much discussed in the finishing industry but hand polishing is generally considered the best treatment for worked products to close the micro-cracking on the surface (with the right wheel and polish you are removing the softer elements on the alloy and smearing the chrome over the pores, you need a 600X microscope to check this is being done properly).
There are a number of tests in the standards for the success of the treatment, which one you choose is also debatable and usually one creates ones own test (we use the standard copper sulphate test and a 30 day brine spray). And then climbers hit them in with steel hammers and wonder about the rust marks, such is life!
Jim
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USnavy
Dec 24, 2011, 3:59 AM
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j_ung
Dec 24, 2011, 4:35 PM
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Interesting! Looking forward to learning how it turns out.
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USnavy
Dec 30, 2011, 9:21 AM
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sungam
Dec 30, 2011, 10:59 AM
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Not only is this interesting, but I think it's rad that you are going through the effort to give the kit your placing longevity. Much more responsible then a lot of equippers I can think of.
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MGNT
May 4, 2015, 3:43 PM
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I have sent off some stuff to these guys http://ableelectropolishing.com/there process of electropolishing/passivation is on the higher end but they also will do a few pieces for free as a sample. 
(This post was edited by MGNT on May 4, 2015, 3:43 PM)
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billcoe_
Oct 2, 2015, 4:37 PM
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FRI, regarding the "bartenders friend" ie Oxalic acid. Nitric Acid, Hydrofluoric Acid, Oxalic Acid and Phosphoric Acid along with a whole bunch of chlorides and other acids (such as sulfuric acids) have all been observed to cause stress corrosion cracking in Stainless.
I'd make sure that you have done a damned good job rinsing all the crap off when you're done, and even then, give pause to using the stuff.
Use of a highly alkaline cleaner should be safe. We have some alkaline stuff at work for stainless that will burn a hole in uncovered skin within seconds that works great for cleaning SS. Maybe try a cleaner like Formula 409 which is an alkaline based cleaner.
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