For the home plating specialistpassivation? Snakeoil, man you got it again, A couple of beers(doesn't even have to be good beer) and working on the bike..........man I'am pacified. I get all oxided up and nothing can get me. I agree with what you a Wilf said above. My voltage was to high. Got a another power unit coming so plating is on hold for a week or so. Good Q about the passivation! Somebody out there will know.
Last edited by zoom on Mon Dec 13, 2010 6:50 pm, edited 1 time in total.
As mentioned previously, I don't know squat about plating. Learning as I go here. I did some reading on passivation and it would appear that you do not need to passivate zinc. I see that passivation is require for plating metals like aluminum alloys because they corrosed so easily. I would guess that they continue to corrode under the plating unless passivated. If I remember right, this is the primary cause of chrome degrading on aluminum parts.
In the case of zinc plated over steel, since the zinc is the sacrificial metal here, I would expect there to be no corrosion of the steel as long as there was some zinc left. I do see that they have passivation chemicals for zinc. I just wonder if this is to allow the zinc to emulate cad plating. The gold chromate seems to be the most common. Caswells has a black chromate that is pretty neat. You zinc plate the part and then make it black. Getting back to steel, one of the more common ways to passivate steel with with a bluing process, like that used on firearms. I'm not sure it add anything to the zinc plating process. Some of these polishes that help maintain a bright surface may be a form of passivation. I've polished the little cad plated ferrules on the ends of cables with Flitz and the stuff stays bright forever. The Flitz will take the gold color off the gold cad plated stuff. But it leaves the cad shiny bright like chrome. Anyone know more about this? regards, Rob Gee whiz, Rob!
First you got me all anxious trying to remember everything I thought I knew about plating zinc and now you're poking my blood pressure higher with passivation stuff? :) Yikes! I'm going upstairs for a glass of wine passivation, and if I wait too long, the wine will turn to vinegar which I can use in my next plating solution.... Wilf
Hi,
@Ed Yes, you bet, you’re getting better and better every day, +1 for recognizing the angle I’m coming from. @ Wilf, rob, I launched this question because I was wondering if it was possible to passivate at home. The chemicals used for the passivate process are hard to get in this environment endorsing small country with all its rules to prevent to anything of the above processes doing it yourself. We live in a country which forbid you to wrench on your car or motorcycle in the street, so you can imagine that doing it yourself plating is a possibility ? If the police finds out that you play with chemicals in your garage, together with electricity, your name will be in the paper (headlines). I bring the stuff away to a plater, a) because it’s cheap, b) I don’t have so much time, and c), like I mentioned, chemicals (metal salts) are hard to get as long it isn’t NaCl. When I bring my stuff away to the plater he always want to know the layer thickness, and what kind of passivation process I want. If I want a yellowish cadmium color (for example the coil brackets), I have to choose another passivation process then when I go for clear color (bolts for example). For anyone who is allergic for ISO and NEN rules and detailed information I advice you to stop reading here. Still reading ? I warned you !!!!!! According to ISO 4042, I order for bolts A3F, ignition brackets A5C and spokes A5F. The first digit is the material, the second is the layer thickness and the third one is the passivation method. Material codes : A (zinc), B (Cadmium), C (copper), D (brass), E (nickel), F (nickel-chrome), G (copper – nickel), h (copper nickel chrome), J (tin). Layer codes : 1 (3 micrions), 2 (5 microns), 3 (8 microns), 4 (12 microns), 5 (15 microns), 6 (20 microns), 7 (25 microns), 8 (30 microns), 9 (10 microns). Passivation codes are : A (clear), B (blueish, matte finish), C (yellowish, matte finish), D (olive color, matte finish), E (clear, matte finish ), F (blue, matte finish, G (yellow, matte finish), J (clear glossy finish), K (blue, glossy finish), L (yellow, glossy finish), K (blue, glossy finish), R (black, matte finish), T (black, glossy finish). Depending on the passivation process the sink layer will be 10 to 100 or more times more durable in salty and humid environmental conditions. At the moment I’m trying Geomet® and Dacromet®LC, it seems that this is even more durable to our humid environment. I like to put a tick layer on bolts, but it still needs to fit. So be careful for bolts and thick layers. I chose the layer according to ISO. I wonder if anyone was waiting for this information, but anyway, I like a complete overview and understanding of what kind of possibility’s there are. Jensen assembly of Japanese motorcycles requires great peace of mind (Pirsig)
Jensen
That's really good information. I have got hold of all the stuff I need to do zinc at home (I'm paranoid about some of my Matchless bits getting lost). My experience in UK of zinc without passivation is that it grows a white deposit quite quickly and generally loses its shine. I normally ask for clear passivation. My plater doesn't ask me sophisticated questions on palting thickness etc. My Matchless parts were originally cad plated (white and dull) I think but I think that home done zinc would be interesting. I would imagine that WD40 or other spray should keep it looking nice. I must do some more research. G '60 C77 '60 C72 '62 C72 Dream '63 CL72
'61 CB72 '64 CB77 '65 CB160 '66 Matchless 350 '67 CL77 '67 S90 '77 CB400F
Hi,
I outsource plating on a regular base for the company. Our machines work in harsh environments, so corrosion must me avoided at all times. I cannot always use stainless steel 316 or 316 Ti or better for every part. Sometimes parts are made of steel, and must be plated. Maybe it seems a bit arrogant to the home plater, but it is not my intension. @G-man, Yes, I got the same experience here for zinc layer which is not passivated, plus the fact that cadmium plating (yellow for the coil brackets) is almost impossible to get these days, and on top of that, it shines (glossy) for a long time. Jensen assembly of Japanese motorcycles requires great peace of mind (Pirsig)
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