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Chrome Mirrors Pimples

Discussion in 'Bling and Appearance' started by kingy, Feb 18, 2011.

  1. hay guys

    long story short i got a set of Chrome mirrors for my cruiser sent to me for free :bannanabutt::dance:

    so seeing they cost me nothing i am still a happy man.. but the mirrors are cover in like little lumpy pimple things.. can this be fixed ???? here is a pic (sorry but my camera is out of batties)


  2. most likely caused by corrosion under the chrome plate. You might find a metal polish that will brighten them up but it wont restore them to pristine condition. They can be saved if you want to do the hard work of sanding/blasting them and then having them re-chromed. If the bike is old and has a few blemishes then they will just add character.
  3. nylon scourer and WD40 will make them better, but Rabbito notes, there's no getting back to original.
  4. cool guys a mate owns a sandblaster and got a quote to rechrome them 50 bucks each
  5. clearasil apparently it's great for pimples

    I have nothing of value to add to this thread.
  6. It happens 'cos the metal they're cast from is porous crap. During the plating process all sorts of corrosives get trapped in the pores and spend the rest of the component's life attacking the chrome from underneath. It was common on the chromed Mazak castings that carmakers were so keen on for trim and door handles in the 50s and 60s and was a perennial problem for restorers because even new-old-stock that had never seen weather had gone all lumpy.
  7. awesome thanks... will be rubbing them back to bare metal and getting them re chromed
  8. Don't like to be the voice of pessimism, but rechroming will likely only start the process again with a fresh load of retained acid in the pores in the base metal.
  9. I had the same problem with the mirrors on my bandit.
    Some Autosol brought them up nice, not perfect but a lot better.
  10. I got some aftermarket mirrors from the US on my bike, havent even been on 10 months and already they are showing those pimples. I make sure my bike is dried thoroughly after washing and the chrome is polished weekly. Just not fair! They cost me a lot of $$$ too.
  11. Makes no difference when, as I've pointed out, the corrosives are sitting under the chrome in the structure of the metal.

    The trouble is, all the many and varied shapes of mirror and stem now available would be hideously expensive to machine from the billet (hence the price of genuine billet components), even with the time and labour saving advantages of CNC. So the budget suppliers get the things cast by the bazillion in China or India or Indonesia. Once the patternmaking's done it's very cheap, particularly since the vast majority are done in various zinc alloys that cost peanuts, melt at low temperatures (400-450 degrees or so) that require no special equipment and are surprisingly strong but easy to work for finishing.

    The one major disadvantage these zinc alloys have is that they're mostly microscopically porous. Not a problem if left in their raw state as they are when used for structural components in pretty much every piece of household electrical equipment and power tool on the planet. But when they're acid etched prior to plating, the pores hold a residue, which is then trapped by subsequent chrome plating and it sits there, eating away at the base metal and the chrome.

    There's not much you can do about it. It's just in the nature of the materials used. The only option is to shell out on gear that is made from aluminium, brass or steel and, if chromed, done properly with layers of copper and nickel under the crome. Anything else will fail and fairly quickly too.
  12. The more I work with Americans the more convinced they are sales-people above all else. In Australia we at least feel guilty if we sell someone something we know they don't need. An American won't even think twice about it. The same goes with quality. We'll at least consider the consequence to future sales of selling a sub standard part to a customer. An American will take the dollar now and worry about the $100 later.