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bryankazmer

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Posts posted by bryankazmer

  1. If you're going to use that approach (and there's nothing inherently wrong with it), you need to be sure the old match has a modern version (I'd still want to see a test spray), because some pigment chemistries have been regulated out since then, such as pigments based on hexavalent chrome or cadmium salts.

     

    For blues and greens, like the OP is looking for, the match is likely to include phthalo blue.  Make sure the concentration is more than tenths of a part, even if it means adding more titanium dioxide to compensate.  Matches with very low content will fade.

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  2. 2 hours ago, 30DodgePanel said:

    Really bad flashbacks of gunmetal. 

     

    Spent the summers of 88 and 89 listening to Pros and Cons of Hitch Hiking by Roger Waters while electrostatic painting with Xylol based gunmetal non-stop (gunmetal magnets reference). 

     

    Xylol is cancer causing garbage, so it makes my skin crawl whenever I see that so called color. Love the ships but that color has to stop... PLEASE!

    Xylol is another name for xylene or more formally dimethylbenzene, if you're reading labels.  Manageable to use with the right equipment, which I doubt you were provided with.

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  3. A spectrophotometer (it's not a camera) works by scanning intensity vs wavelength of the light reflected off the sample.  It has had the pigment curves and paint base color curves for that company's raw materials in the computer already.  It overlays the curves until the best fit to the sample is found.  The more pigments that have been scanned into the library, the better the matching can be.  It does give a formula for the proposed match, that's the whole point.  The best computer match should be tested and tweaked, as well as viewed under different illuminations and angles.

     

    Old mix formulas based on obsolete (and often now forbidden) pigments and bases are next to useless unless the company has already done work on characterizing conversion.

     

    A skilled color matcher (there are actual tests for a person's ability to see subtle color differences) can match without a spectrophotometer, but it's by an intelligent guess and iterative samples.  It's takes more time and money.

     

     

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  4. I agree that any competent place will use a spectro (Not on metallics - the light scattering confuses the spectro).  But there is more - you want a formula with right "travel" or "flop" - how viewing angle changes the color.  Also a metameric match will look good under one lighting but not under different lighting.  A test spray of the proposed match before committing is in order.

  5. Neither.  There are no VIN's in 1928.  The firewall tag should be the serial number - someone smarter than I can decode it.  Packard body, serial, and engine numbers do not normally match each other.  So long as one matches your title you should have no problems.

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  6. I used to run a lab where we ran certified testing, but not these.  ASTM, ISO, DIN all sell their test standards.  You have done some good detective work and have the actual test results.  They tell you what happened on the standardized tests. View the results as the likely relative performance in the car, but "your mileage may differ."

    Your home made one is not bad at all - the main issues are the viscosity change as the temperature changes (I'm nearly certain the ASTM tests will run at controlled temperature to greatly reduce this) and mixing the same way each time.  I'd suggest marking the inside of the bowl with level lines.  Fill to the same line each time and note the height of the foam, as well as timing the mixing and foam decay times.

    As I think you understand, colorant is added and means absolutely nothing intrinsically.

    If you want to change to a different problem, you could try an alcohol/water coolant.  However, it requires routine checks to replenish against evaporative loss.

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