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Prepping/painting wheel

Discussion in 'Wheels & Tires' started by az3579, May 2, 2009.

    • Member

    az3579

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    Yes, I was going to skip the stripping step for my other wheels. I hear that the scotch brite pad works wonders.

    I kind of do. Of the places I went to to *try* to get my test wheel sandblasted, half of them said not to do it on aluminum as it will damage it, and the other half said go ahead, but they didn't offer sandblasting. It's pretty hard to find a decent sandblaster 'round here, but I did only check about 4 places, so I'm sure there are some around. Even if I did get the wheels sand/bead-blasted (I would prefer bead-blasting), it kind of diminishes the reason why I'm doing them myself: cost.

    Agreed. I realized this after I finished, and thought that perhaps I should just spray the lip without covering and THEN mask it. Thanks for reinforcing the idea; this is what I will do the next go around.

    What do you mean "center lug nut"? Can you explain this bit here?





    EDIT: Paul, I forgot to mention;
    I applied two coats of aircraft stripper, scrubbing the paint off between applications. Is the primer that gray coating on the wheel? I thought that was the metal portion...
    I didn't continue because I thought I was damaging the wheel.
    • Member

    granthr

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    By center lug nut CR was referring to the large plastic nut on the center cap. It is suppose to look like the center nut used on race cars or old British cars with a knock-off center nut. In other words that large plastic nut is suppose to look like it is holding the wheel onto the hub.

    IMHO it looks good, but does not achieve the effect they were going for.
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    az3579

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    Right, the center caps are going to be painted! I only put the unpainted center cap on to show the color difference. lol


    But CR, do you mean paint the center cap and leave the "nut" unpainted? I was going to paint the entire center cap, including the nut...
    • Member

    MGarrison

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    I believe CR meant painting the faux 'nut' a contrasting color, and the rest of the center cap the same color as the wheels. I'm no paint expert, but as far as I know, the point of 'prepping' anything for painting, is so the paint will adhere to the painted surface. Aluminum is a soft metal - sandblasting and bead blasting would clean or strip all paint and primer off, while simultaneously pitting or micro-pitting the metal, making it really difficult to put a smooth finish back on the wheels. When it is suggested to prep for painting by scuffing, that's all you really need to do. Get the wheels clean and get off all dirt and brake dust. New paint/primer won't adhere all that well to the smooth surface of a already painted wheel, you need to roughen the painted surfaces of the wheels just enough so the new primer and paint can adhere. In your first close-up shot of your prepped wheel, the silver flecks are remaining bits of paint, the light grey is the primer, and in that picture, the darker gray (left top edge of the center section of the left X cross-spoke) shows your down to bare metal there. You should be able to feel the lip edge of the primer, which is slightly higher than the base metal, with your fingernail. So, you got most of the paint off, and you see how much further you'd have to go to get it down to bare metal, plus just how well adhered the original primer is, and why it's so much work to manually take it down to bare metal that in most cases, no one bothers or needs to, when trying to freshen up the finish when repainting wheels. You wouldn't be damaging the wheel until you're through the paint to the bare metal, but the combined thickness of primer, paint, & clearcoat is only a few mils. Good luck w/ the rest of the project!
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    CRKrieger

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    No; I meant to paint the fake nut in a different color so it looks like a different piece. One reason I like the TSW Hockenheims I have is that the lug bolt cover is a separate piece held in place by a real center nut. These nuts are (on mine) black, blue (a set I could get from a friend), and red (what would actually match my car better). This is the red nut and this wheel has the even cooler wire keeper that mine don't have:

    [IMG]
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    Brian A

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    Makes sense. If the old paint surface is smooth, there is no need to remove it. Just lightly scuff and repaint.

    As you've discovered, new paint doesn't fill-in rough spots so its all or nothing in terms of old paint/primer removal.

    In terms of "damaging" the aluminum with paint stripper, its doubtful you could actually cause structural damage. The only damage you might cause would be minor cosmetic etching. Since you're covering with paint, it wouldn't matter. Yeah, sometimes using paint stripper requires many applications to remove all of the old paint: a major pain.

    Hopefully you can just scuff and repaint.

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