For the home plating specialistWell you guys are all right. Got my meter squared away. With my big Battery charger set to 6v,2amp at "maintain" setting its pushing about 250-300milliamps. With the train transformer (not solid state), I can go higher but it over heats after about 15" at about 500Am which seems to be the amount that works best time wise and effect, and Snakeoil I do see current go up as items are added and as plating time increases. New power source on order. Lots of plating to do.
Fixing damaged chrome partsOkay, my day of plating is over. Wife is downstairs with my niece baking Christmas cookies and soon she'll be popping the stuffed eggplant into the oven. So it's a perfect time to give you a lowdown on what the subject of this message implies.
As most of you probably know by now, the chrome plating on the operating arms and the threaded rod between them on the front and rear brakes of a CL77 is not what you would call "show chrome". From what I can tell, it is just a coat of chrome applied directly onto the steel parts. I think I read in another post that Honda used what is called "flash chrome". Not sure if that is the right term. But judging by the quality, I would say that "flash" decribes the amount of time the part was in the plating bath. So, my chrome brake parts were ugly. They were pitted, chrome completely missing in some areas, like I said ugly. Looks like the PO hit some of the areas with a wire wheel and then clear coated over the entire part with rattle can clear. Probably not a bad idea, but not really durable. I have to admit I did not notice the clear coat until I started to degrease the parts and scrub them with a wire brush. So I got this brainstorm that I might be able to plate the chrome parts with the intent of plating over the pitted and missing chrome areas. Here is the process I followed that ended up working like a champ. 1 Degrease the parts - I use mineral spirits 2. Soak parts overnight in Phosphoric Acid. The acid will not hurt the steel base metal, nor the chrome. But it will eat the rust. With a new (straight bristles) steel wire brush, brush the parts after they've been in the acid an hour or so to loosen up deep rust, especially in the small pits. When they've been in the acid, over night, give them a good wire brushing (I'm talking hand brushes in ALL cases here) and then just rinse in water. One rinsed, blow them off/out with compressed air. Make sure you blow out the threaded holes. At this point it is a good idea to wash your hands thoroughly with a dish detergent like Dawn. It will degrease your hands so you don't have to wear gloves. 3. Degrease the parts again in acetone or similar. Blow them out with compressed air. 4. Set up your plating system and put in your first part. These are all relatively large parts so do one at a time. Plating cycle. Plate for 5 to 10 minutes, depending on the size of the part. Remove. In a bucket of clean water, scrub with a brass wire brush. What you will find is that the plating will just pop right off the areas that are still chrome plated. That's okay. Keep scrubbing until all the chrome is no longer plated with zinc. Take a look at the unplated areas, especially the pits. Use a 10X loupe if you have one. If any pits are dark, there may be rust still in them. Clean them out with a needle or steel wire brush. Plate again, for 5 to 10 minutes. Remove and scrub again in the bucket of clean water with your brass wire brush until all the chrome is unplated again. Repeat the above process until you have all the unplated areas, replated with zinc. You will find that the color of the zinc is just about identical to the color of the original flash chrome. Once you are through plating, you can polish the zinc with Flitz, Simichrome or Mother's and it will shine as good as the chrome. Personally I prefer Flitz because it leave a protective layer behind that keeps it looking like chrome for a long time, years in some cases. The pictures that follow show parts polished with Mother's because I was out of Flitz. That's pretty much it. What you end up with is your original chrome part with all the missing chrome replaced with zinc. This should do two things. First, it will protect those areas from rusting in the future because the zinc is sacrificial, and second, it will make the part look a lot better. No, it will not, as you will see in the pics, fill in the pits. I suppose you could keep plating until you filled the pits, but I was not interested in that. The nice thing is if you ever decide to have the parts rechromed, the zinc will simply strip off when they dechrome the parts prior to polising and rechroming. I tried to shoot the before and after pictures to provide a true representation of the parts and the plating. To help with that, let me describe the front brake actuating lever. The polished side (Honda only polished the side that shows) was missing most of the chrome on both legs to either side of the splined hole. Those areas appear dark in the pics because they are raw steel and the rest of the areas are chrome plated. The after pic shows that entire area a bright silver. I did polish that area after plating. I cannot tell where the chrome ends and where the zinc begins because the surface prep for these parts is dismal so even when the chrome was brand new, it sucked. But that turns out to be to our advantage. What you cannot do is take something like a damaged chrome fender, which has decent chrome, and make it look new. But I would say that if you had a headlight bezel with a rusty scratch on it, you could clean off the rust and plate that area with zinc, polish it and only somebody looking for it would notice it. Okay, that's enough babbling. See the pics for before and after results. I've labeled the pics so you know what you are looking at. Also, because of the way pictures load on this forum, you should view them from the bottom, up, to get the before and after effect. Gotta keep that in mind for future picture posting. Also note that any dark pits that appear in the after plating pics are shadows. Those pits are all plated with zinc. One last comment before closing. Take a close look at your chrome plating under a 10X loupe if you are going to do this. If you see a tiny blister in your chrome, that means there is a tiny hole and the steel is rusting underneath. I would suggest you hit the area with a fine tooth file or dental pick to break the blister and expose the steel. Then derust as described above and plate it with zinc. Otherwise that pit will continue to grow under the chrome. Those huge pits in my parts started out this way I'm sure, and it was not until the were very deep that the chrome blister finally broke away. regards, Rob The Mad Plater
They look good, Rob! I did pretty much the same thing to a front brake sttopper arm for the same reason--what you refered to as "flash chrome". It worked out ok until I found a source for an arm with the chrome still intact. The acid treatment and lots of srubbing is required in order to get at all the rust. One thing I don't recommend is using electrolysis on rusty chrome--there is apparently a risk of releasing harmful gases and/or compounds into the electrolyte.
Wilf Thanks Wilf. I figure they look good enough for somebody standing next to the bike and taking it all in. A judge would spot the pits in a second. My hope is it will prevent further rust attack to the already affected areas. Trouble with the crummy chrome on these parts is there are probably plenty of other areas that have already started to rust under the chrome and you just cannot see it yet.
Zoom, After thinking a little more about the bubble/no bubble observation you made, similar to mine, after the bath has some hours on it, my guess is the bath is saturated with zinc for the amount of acid in the bath and the reaction stops. That's a good thing because it means a zinc ion rich electrolyte from which to plate. I probably should not have tossed that first batch of electrolyte when it quit bubbling. I'm pretty sure now that it was an electrical connectivity issue and not a bath issue. I probably threw out a really zinc rich bath. Based on this, I'm going to save my zinc scraps to feed new batches of bath. Cut it up and drop it in the jug of electrolyte and let it dissolve in the acid. Although it might require current to really saturate the bath. regards, Rob regards, Rob Snakeoil, zoom;
I've been following your observations and trying to remember details from my own experiences since I last plated (about a year ago). The only real difference between your methods and mine seems to be the voltage and possibly current. Here's what I think is happening with bubbling and plating efficiency: The bubbling you see on the cathode (part being plated) is Hydrogen gas produced by the breaking down of water. This breakdown is not a result of the zinc transfer--rather the opposite. It occurs when the voltage is too high compared to the amount of dissolved zinc ions. Water is H2O and when the voltage strips off a hydrogen atom it leaves OH in the solution, and the OH radical, neutralizes the vinegar (OH is a base and vinegar is an acid). I think your observations, Rob, bear this out. With your first solution there was active bubbling at the beginning because of a shortage of zinc ions. When you loaded up your second solution with zinc prior to plating, the efficiency was much better, but because of the high voltage (compared to mine and to the 1.5v needed to make it work), zinc was being plated on the cathode faster than it could be dissolved/replenished into the solution. With the voltage still there but no zinc ions to act on, it begins to tear apart the water and neutralizes the electrolyte. My suggestion would be to bring the voltage down to the lowest useful level to reduce water breakdown and also to use the current to control the plating speed. Another suggestion would be to replenish the solution with more vinegar--that way you don't throw out your zinc ions. I'm trying now to think of easily obtained pH test kits that you could use to confirm my suspicions. One post mentioned hot tub testing material, maybe garden shops sell stuff for measuring soil, I haven't looked in a pharmacy for this but you never know. It's been very useful following your plating adventures. I think I have a much better understanding of how it works and how to keep it working optimally. Wilf Snakeoil; I also have been doing some zincing of some (originally) chrome parts. you can get away with it on the small stuff. the part will have already flaking chrome and the rest of it will come off by sand blasting the living crap out of it. on most old Honda parts this will get you down to bare steel (with maybe a hint of copper), both of which will take the zinc. after blasting you can work at the pitting with sandpaper, you won't get it all but it will really help. couple rounds of plating,brushing and from five feet it will look pretty chromey .
Randy
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