Editing First paint job
(
diff
)
← Older revision
|
Latest revision
(
diff
) |
Newer revision →
(
diff
)
Jump to:
navigation
,
search
{{youcanedit}} ==Cheapo paint job== Paint is expensive, and learning how to paint your car takes practice, patience, and several screw-ups before you get it right. Faced with the financial obstacle and the learning curve, many hotrodders are tempted to opt for a "cheapo" paint job. The two biggest temptations in the "cheapo paint job" realm seem to be an inexpensive (and questionably professional) paint shop (ie: Maaco), or a cheaper, easier, and ostensibly more forgiving product line (ie: DupliColor). If you've put any amount of effort or money into building the mechanical aspects of your hot rod, you will most likely want to complete the project with a proper paint job. "Cheapo" solutions work fine for beaters and work trucks, but they aren't appropriate for non-Cheapo vehicles. As with most other aspects of constructing your car, when it comes to paint, you get what you pay for. Cheapo paint shops do low-quality work. Cheapo, "easy-to-use" products will never provide a quality, long-lasting finish of which you can be proud. Nevertheless, many newcomers are still tempted to opt for the cheapo route, a path against which body shop professionals frequently advise. For a full explanation of why, in most cases, a cheapo paint job is a bad idea (and, suggestions for when it's '''not''' a bad idea), see [[Cheapo paint job]]. Last but not least, these materials can do major harm to your health if you do not closely follow the manufacturers recommendations for skin and lung protection. Appropriate respirators must be used! == General Tips, Tricks, and Techniques == '''Temperature, Temperature, Temperature...''' Warm and dry conditions are ideal for spray painting. The ambient temperature range for spraying most modern paints is about 65-90 degrees Fahrenheit. Be sure to choose the hardeners and reducers for the temperature range you'll be working in. Aerosols don't always work best in the damp and colder temperatures, which can hinder drying time, although it can be done. If it's not warm and dry outside, work in a well-ventilated garage, but set it up for painting. Try to keep your gun straight not angled to far up or too far down. Keep the gun about 5 to 6 inches from the surface the whole time or you will have heavy painted surfaces and lightly painted surfaces. Practice spray technique on an old fender to determine proper gun adjustment, pass speed, and pass overlap. '''How to make your own temporary paint booth''' Painting in a garage lessens the chance of bugs or dust ending up lodged in your paint while it is still in its curing stage. One way to turn your garage into a temporary paint booth is to get huge plastic drop cloths from you local hardware store or home improvement store. They are cheap and effective for protecting your tool boxes and "toys" (Atv's, etc.) from over spray. Open up your garage door about 1/8 to a 1/4 way up, this will help with ventilation, since solvents sink to the floor. Place a fan near the opening, facing outside, to help even more with airflow. Opening any side doors and roof vents helps lots too, Place another fan around here. Box fans may work, but at a minimum you should ensure that these fans are the brushless type to reduce the amount of sparking the exhaust stream will "see". Remember, the fewer sparks the paint vapor "sees" the less likely you are to cause an explosion. An even better solution to box fans would be to use squirrel cage blowers, commonly found in HVAC and exhaust vent systems. Try to get the type where the motor is outside of the squirrel cage to reduce heating the exhaust stream. Place the squirrel cage blower motor outside of your "paint booth" and run ducting into (or out of) your paint booth. A good rule of thumb for blower sizing is to try to change the air TWICE every minute. Hence, if you have a 10'x10'x10' paint booth (1000 cubic feet) you want a 2000 cfm blower (2000 cubic feet per minute). Something that will help keep dust and bugs from coming into your garage is to buy a furnace filter the same size as the window (or build a frame for the filters to go over your door)that you have open. This will collect the dirt and bugs that want to invade what you're doing. If there are strict rules in your area, something that will help is to place a filter before your fan so that it filters the air as it is leaving your shop. '''Basic mixing techniques''' Paint and related finishing products can be mixed in glass measuring cups, medicine cups, soup cans, or shot glasses. However, EZ Mix cups are generally preferred for ease of use. Containers with measurements marked on the side are generally most useful. Paper cups are cautioned against because some may have a wax coating. Similarly, plastic cups or containers (medicine cups, yogurt containers, cleaned bottle caps, etc.) are also cautioned against. There are many different kinds of plastic, some of which are inappropriate for storing certain types of finishing products. When mixing double portions of paint or primer, mix one portion at a time. For example,''''' 8:2:1''''' is easier to keep track of than '''''16:4:2'''''. Most, if not all, automotive paint has the correct ratio for the paint/thinner/hardener printed on the label. If not, consult your favorite body man for the best ratio to use on your paint. After mixing each individual portion, add the two portions together and mix well again. This also cuts down on wasted material if you make a mistake (too much hardener, wrong reducer, etc.). ''TO HELP YOU ALONG THE WAY'' GREAT TIP '''When opening a can of paint, punch a few holes in the trough where the lid sits with a hammer and nail. That way, excess paint will drain out of the trough and into the can, rather than splattering when placing the lid back on the can.''' -Buy a set of inexpensive spatulas to use as scrapers for paint cans. -To preserve hardener, displace the air in the can with inert gas, such as the shield gas (CO2/argon, etc.) from a MIG welder (DO NOT USE O2 OR ACETALINE FROM A GAS WELDING UNIT). Or, use a commercial inert gas finish preservative such as Bloxygen. -For easier pouring, affix a 2-inch piece of masking tape to the edge of a large gallon of paint. Pour the paint over the piece of tape. -Use a ladle for handling paint. -When purchasing new paint or other finishing products, write the date on them with a black magic marker. -For stirring paint, use inexpensive "jumbo sticks", tongue depressors, Popsicle sticks, wood sticks, or butter knives. GREAT TIP '''Paint stirring sticks with marks for different mix ratios can be useful for mixing paint.''' When opening a gallon of paint that isn't all going to be used immediately, mix it very well and pour it off into quart cans. You can get empty quart cans from a local (private, not chain-store) paint shop for cheap or free. While pouring, intermix the paint; pour a little bit into each can at a time. GREAT TIP '''Leftover paint with hardener can be placed in the refrigerator. The cold temperature will slow down the hardener., you can even throw you spray gun in there if you find you need some supplies, and you are in the middle of painting!''' ==Proper Paint Clothing== When painting it is always a good idea to wear some kind of protective clothing it not only helps keep you from contacting the toxic materials but it also will help keep unwanted materials from getting on your paint job. The first and most important is a paint mask made for '''automotive''' refinishing there are a lot of companies that sell these. Get a paint suit or use a lint free pair of coveralls. The next thing is a pair of gloves, latex style; I have found that the nitrile gloves hold up better to the chemicals. Do not use a set of rubber gloves they are too clumsy and you need the motion that you get from the latex style gloves. Get some kind of lint free head cover, this keeps your hair on your head and not on the job you are working on. They also recommend a foot cover (which I never used) but they look like a sock for your shoes. There are many different companies that these items can be purchased, local stores and Internet. The most important item that you need is a paint mask. You can get by with out the other items (with extra buffing when you are done) but the '''paint mask''' is the most important. Before entering the area that you are refinishing your project in take a air nozzle and blow yourself off. This will get rid of any extra surprises that will fall into your job == Spray gun Tech == With any spray gun, you get what you pay for! HVLP (High Volume Low Pressure) is the way to go when buying a spray gun although LVLP (Low Volume, Low Pressure) can work acceptably with the right paint. The prices have come down to reasonable levels, and the wasted paint by over spray (Not to mention the mess) makes a siphon-feed unit a poor choice for the home hobby sprayer. Remember that high-solid primers like high-build type 2k urethanes require a larger (1.7mm) tip and setup internally than a regular paint gun. 3-gun sets are available for as little as $100 that include a primer gun with the larger tip, a paint/clear gun, and a 1.0mm tipped touch-up gun. Cutting (wet sanding) and buffing make up for a lot of shortcomings in inexpensive HVLP guns. So determining which is more valuable, your money or your time, is a determining factor in choosing a paint gun. A cheaper gun will require more time spent cutting and buffing than a top-of-the-line gun that lays paint out more evenly, but at an added price of several hundred dollars. A budget gun can be had for under $30, whereas a SATA 3000 digital runs around $650. You decide which is more important. Most folks will spend a little more time cutting and buffing than spend the extra on the fancy gun. The difference can be spent on go-fast goodies! == Choosing the right type of paint == See "How to mix and spray urethane enamels" for a basic primer on the types of paint. Whatever it is, you can ask other car builders that have done their own paint work, or if you know a painter, ask them. Best of all is to consult with the paint salesperson when you go to buy paint. They are a wealth of information. Utilize them. That's what they are there for. ''TWO MAIN TYPES OF ALL AUTOMOTIVE PAINT COLORS'' '''''SOLID paint''''' Solid colors are a little easier than metallic to paint. If you mess up and get a run in them, they can be fixed rather easily by color sanding and buffing. '''''Metallic paint''''' Spraying metallic is a little different then spraying a solid color, they will mottle (have blotches of dark and light areas) and tiger stripe if sprayed incorrectly. The key to spraying metallic paint is to move the "dry spot" around. For example, spray one coat one direction, then the next coat in the direction 90 degrees to the first coat. Overlapping the coats up to 75% is another key to good metallic finishes. Remember anytime that the paint moves the metallic does as well, so if they run you will get the metallic all in one spot. With metallic always use the suggested reducers and mix the entire batch to be sprayed at the same time. I recommend this ANYTIME you paint. DO NOT play mad scientist/chemist. FOLLOW the instructions to the letter. The engineers at the paint companies spend millions on R&D, so they are already sure of the results you will get by mixing the product any given way. You, however, as an amateur, are not. Do not re-invent the wheel. == How to mix and spray Water based paints == == Paint Defects and Flaws == '''Orange Peel''' The most common paint defect, is caused by the paint being broken into small particles by the spray gun. It lands on the vehicle with little spaces in between droplets, leaving the texture, similar to the surface of an orange, behind. This is where the term "Orange peel" comes from. It is easily fixed by sanding the surface flat with 1200 grit sandpaper then polishing with a high-speed buffer and compounds. '''Fish Eyes''' Fish eyes are a separation of the paint normally resembling the look of a fish eye. These are areas where the paint will not adhere thus making small craters in the paint. Fish eyes are always caused by contamination. The oil naturally present in your fingers is probably the number one cause of fish eyes. You will see most all good painters and body men wearing latex gloves similar to what doctors wear when prepping a car for paint. Wax, silicones, diesel fuel, and products such as Armor All can all cause the problem. The contamination is usually on the surface being painted but can also result from contaminated paint and contaminated air. Using a wax and grease remover, proper air filters and general cleanliness around the paint area should stop the occurrence of fish eyes. '''Solvent Pop''' Solvent pop is tiny pinpoint size craters in the paint surface. This defect is produced when the top surface of the paint dries before the lower portion resulting in trapped solvents. The trapped solvents escape explosively through the dry skin of the paint leaving tiny craters. Solvent pop most often occurs because the job is being rushed either with flash times or the speed of the products. Most times they can be prevented by slowing down the painting process. Adequate flash time is essential to prevention as solvents need time to escape. Slower reducers and activators can also be used to prevent solvent pop as this too allows more time for the solvents to escape. Solvent pop can also be caused by excessive air movement which causes the top surface of the paint to skin over too fast. == How to finish off your paint job (Buffing) == Buffing is a whole other technique that you do when painting your car, it will be discussed in detail in its own article: [[Buffing your newly-finished paint]] [[Category:Body and exterior]] {{youcanedit}}
|
Editing help
(opens in new window)
Template:Needspics
(
edit
)
Template:Rounded
(
edit
)
Template:Warning
(
edit
)
Personal tools
Log in / create account
Namespaces
Page
Discussion
Variants
Views
Read
Edit
View history
Actions
Search
Navigation
Main Page
Recent changes
Random page
Help
All articles
Start a new article
Hotrodders forum
Categories
Best articles
Body and exterior
Brakes
Cooling
Electrical
Engine
Fasteners
Frame
Garage and shop
General hotrodding
Identification and decoding
Interior
Rearend
Safety
Steering
Suspension
Tires
Tools
Transmission
Troubleshooting
Wheels
Toolbox
What links here
Related changes
Special pages
Terms of Use
Copyright
Privacy Policy
Your Privacy Choices
Manage Consent