First paint job

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(How to mix and spray Laquer)
(How to mix and spray Urethane Enamel)
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== How to mix and spray Urethane Enamel ==
 
== How to mix and spray Urethane Enamel ==
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FIRST OFF: URETHANE ENAMELS, WHEN MIXED, ARE VERY TOXIC TO HUMANS. You MUST wear a VOC compliant repirator at minimum when using these type of paints. A fresh air system is recommended, as is a painter's suit. They omit Volatle Organic Compounds, which are deadly the the human liver. DO NOT try to paint at home without an approved resirator, at the minimum. Ask your paint salesperson which one to buy. 3M makes a good one for under $20.
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Urethane enamel comes in two forms: Single stage, and Base coat/Clear coat. Single stage is the easiest to use, simply mix the two parts together, (The paint and the hardener) then reduce to spray and go at it. The single stage paint like the base/clear, dries chemically by cross-linking together at a molecular level. Old lacquer paints and the Dupli-Color stuff at the local auto parts store dry by evaporation of solvent leaving the paint behind. Uretahnes are MUCH stronger, as the name implies, they leave a urethane (plastic) coating on the car. Much better then old technology like lacquer.
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Base/Clear, the other type of urethane, works a little differently. You first spray the color on the car, (The base coat) then apply a few coats of clear urethane over the base coat. The base clear has advantages over single stage, so let's comparethe two.
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Advantages of single stage urethane:
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1. Ease of use. Mix and spray, then walk away. You are done. Dries to the touch in a few hours.
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2. Durable
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3. Inexpensive. Single stage can be bought for around $50/gallon, enough ready to spray paint for an average car.
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4. Can be had in most any color.
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Disadvantages:
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1. Harder to repair a section if you mess up, (runs, etc.) and/or ding/scratch the car later. Cannot be blended as easily.
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2. Cannot be color sanded and buffed if metallic paint is used. What you spray is what you get.
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3. Bugs, dirt, etc., are harder to get out of finished product unless a solid color is used.
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Now let's look at Base/Clear....
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Advantages:
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1. VERY hard to run the base coat, it sprays like lacquer. Easy to blend.
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2. After clearing, can be wet sanded and buffed to a mirror finish. Easy to remove bugs, dust, etc.
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3. Only slightly more expensive than single stage when budget brands are used.
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4. Easier to use when multiple colors are used on the same car. I.E. stripes, etc.
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Disadvantages:
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1. Extra step involved. You spray the base coat, then have to spray the clear over it.
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2. Extra materials to mix.
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3. Slightly more expensive than budget single stage.
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Mixing and spraying:
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Mixing urethane enamel is really simple if you can follow basic instructions. They are right on the can, and most big manufactures' have the tech sheets on their websites to show everything you neeed to know about mixing it.
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The person at teh paint store when you buy your paint will prove to be invaluable when you talk to them and ask questions.
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The basic recipie for urethanes (single stage)is this:
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Mix one gallon of color
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One quart of hardener
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One quart of reducer
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Go spray it.
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This varies from brand to brand slightly.
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All you do then is spray away. REMEMBER, once mixed, the paint starts to cure and will be set up in an hour or so. If it sets up in your paint gun, you have a more-than-likely dead paint gun. Toss it in the garbage.
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Base/clears work in a similar, by slightly different way. You mix
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The gallon of paint base
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A half gallon reducer
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and sometimes a few ounces of an activator
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then spray it out.
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The clear mostly simply is one gallon of clear to
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one quart of activator.
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Spray it out.
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Base clear can be cut after a couple days depending on the clear used. Then you have a finish that is UV ray
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resistant, (READ: doesn't fade in the sun)and easy to care for.
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Spraying: These paints are applied in a two or three coat method, depending on the product. Base coats, for example, are applied in a couple coats or until everything is covered. Clear is applied in three or even four heavier coats to allow for wet sanding and buffing. Single stage is applied in 3 coats normally.
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HVLP (High Volume Low Pressure) paint guns have become so inexpensive that is is silly to try to paint without one, due to the amount of paint wasted by overspray using an old style syphon-feed gun.
  
 
== How to mix and spray Waterbased paints ==
 
== How to mix and spray Waterbased paints ==

Revision as of 21:54, 25 October 2008

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