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Truck Painting FAQ's |
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NOTICE: This article was originally posted on off-road.com, but can no longer be found there. It has been preserved here after finding it in the Internet Archive. INTRODUCTION Over the past five years I have painted two complete vehicles and did some spot repair on one other. While the thought of painting your own vehicle might scare you, it is really pretty easy to do if you follow the one big cardinal rule of auto painting: TAKE YOUR TIME! In what follows I will attempt to prepare you so that you can paint you own vehicle. We will look at what equipment is required, how much it costs, the procedure to paint your vehicle and other issues. Before I get too far into this I should explain that I am by no means an expert. I have learned many new things with each paint job and I expect that I will continue learning with each new vehicle I tackle. If this is going to be your first vehicle, it helps to have an attitude that you have nothing to lose if you try it yourself. Minor imperfections in any paint job are EXPECTED. Maybe that should be cardinal rule number two. One thought here is that you could start by painting something besides your car, like a metal chair or a spare door from a junk yard. This is a good way to get started and if you mess up, no big deal. There are four basic steps when painting a vehicle: Each of these will be discussed below in more detail and we'll actually expand the four steps to about a dozen. EQUIPMENT Air Compressor - This is the most costly piece of equipment you need to paint a vehicle. I have painted my vehicles with a Sanborn 3.5 HP compressor that has a 20 gallon tank. I recommend this as a minimum. A compressor such as this runs around $250. Sears and Cambell Hausfield are two other brands that are quite popular. You can use a smaller compressor, but my experience says that you need at least close to the above configuration to be successful. The highest psi I ever utilized in painting was 60 psi. Most compressors can easily do this. It is helpful if your compressor has enough hose to go half way around the vehicle. I'm sure you can rent compressors if you can't afford to buy one. D/A Sander - A D/A is not a grinder. It moves in an oval fashion and does a much better job at sanding chores (as in, it is not as hard on the surface). Your D/A sander runs off the air compressor. You can sand by hand, but for anything below 220 grit, using a D/A is much easier. Again, it can probably be rented, or purchased for $50. Paint / Spray Gun - This is "spray can" if you will. When hooked up to the paint can (which is part of this - it can be removed and filled with paint, primer, etc) and the air compressor, this delivers the paint. Must guns have triggers (basically on/off levers) and two adjustments which determine the air / paint mixture and the amount of paint delivered. Together these determine the pattern the paint is laid on the vehicle. I am definitely not an expert here, so consult your local paint guru. Basically you want a circular pattern, where the top and bottom parts of the circle are stretched up; I guess it is somewhat like an oval. It can also probably be rented, or purchased from anywhere from $30 to several hundred dollars. I painted all my vehicles with a cheapo $30 model and it seemed to work fine. Strainers - You should have strainers so that when you put the paint or primer into the can, it filters out any impurities. It is also a good idea to have a strainer on the paint intake inside the can (on the gun). These latter strainers clip-on the spout that takes the paint up to the gun. You need about five of the former and three of the latter (although the latter can be re-used in a crunch). These should run you less than $5. Stir Sticks - As expected, these are used to stir ingredients together. You need about five of these. Any real paint store will throw these in for free (in fact, they should throw in the paper strainers above for free too). Water Remover Filter - I don't have any fancy equipment, but such equipment does exist that removes any water from the air line so that you don't get water mixed in with your paint. I bought the cheapo disposable ones that go between the air line and the paint gun. These did me just fine. The disposable filter it about $5. Gloves - As paint is a chemical and hence dangerous, you should always were rubber gloves when preparing the paint, painting and cleaning up. Gloves are probably around $10. Face Mask - You should have a mask which covers your mouth and nose. They sell cheap masks which use disposable charcoal canisters. This is a must - don't think you can sacrifice your health in this exercise. This is probably around $20. Sanding Block - You'll need a $10 sanding block to handle the sand-by-hand stuff. A small one that fits in your hand should work well. If you are doing body work, you might want other exotic stuff (cheese graters, large sanding blocks, dollies, etc). FINISHING PRODUCTS There are at least three different types of paint. Lacquer was popular a few years ago, but has fallen out of favor and according to one paint expert I talked to, it is being taken off the market. Urethane is probably what most truck owners would love to have on their vehicles since it is quite hard. However, urethane requires a full oxygen ventilation mask and body suit and is therefore inappropriate for most people. It requires this "hardware" becuase it contains poisonous chemicals that the body cannot handle. The most popular paint for the do-it-yourself crowd is enamel, and specifically, acrylic enamel. This paint lays nicely, is cheap and is easy to fix if you make a mistake. In addition, it is easily available. This text is written assuming that acrylic enamel is being used. There are several different paint manufacturers. I have always used PPG products and they have proven to be an excellent choice for me. Dupont is another popular manufacturer and I suppose there are others. This text is written assuming that PPG products are being used. So what do you need to paint a full-size truck? I cannot say for sure, but when I painted my full-size Chevrolet Blazer (including under the hood, door jams, interior and rear bed, but not including the canopy as I painted that another color), I used about a gallon at each stage. Here is a rough idea of what you need, including quantity and cost. Primer - A gallon of primer is enough to paint and seal the vehicle. Primer comes in several colors (grey, green, white, red, etc.) and you should choose the color wisely. Try to match the primer color to the final color and don't use red primer if you are going to paint your vehicle white. The cost for a gallon of primer is about $60. The cost for a quart is $22. I used DP40 (gray) and DP48 (white) in my past applications. Catalyst - You'll need about a gallon of this also. You mix the primer and catalyst together in a 1-to-1 fashion, possible let it sit for 30 minutes to mix together (depends what catalyst you use), and then paint. Cost here is about $59 for a gallon. I used DP401 here (you can also use DP402 which doesn't require a 30 minute induction period). Paint - This will no doubt have to be custom mixed. There are tons of color books for you to pour over to pick your color. Your best bet is to find a vehicle on the street that has your color and then go find that color in the book. I have never tried a metalic paint, but have been told they are harder to lay and especially correct if you make a mistake, so I would stay away from them if this is your first time. A gallon of paint is required and will run you about $68. I used DAR here. Enamel Reducer - They make reducer in several temperature ranges (cold, medium and hot). Pick the right temperature so that the paint doesn't dry to fast or slow. A gallon of this will run about $16. I used DTR-602 (602 is the medium temperature reducer; 600, 601 and 603 are the others I believe). Hardener - You don't need much of this, but the stuff is like gold. Plan on spending $33 for a PINT of this stuff. I used DXR-80 here. You'll need this at both the paint and clear coat stages. Clear Urethane - While you cannot lay urethane paint due to the poison in the reducer, you can lay a clear urethane coat over the paint to protect it. This is highly recommended, but is an optional step. The cost for a gallon of this stuff is about $58. I used DAU-75 here. MISCELLANEOUS Sand Paper - For your D/A sander, get 5, 5 1/2 or 6" sticky back, round paper. You'll probably want 40, 80 and 220 grit for this. For hand sanding, you'll want lots of 400 grit and maybe even 500, 800, 1000 and 1200. Plan on spending $20 on sand paper. Bondo - I'm not going to discuss body work here, but if you have to do some, you might need this magical stuff. Masking Tape - Get 3M painting products. Cheap tape will not do. When you remove it, it will tear the paint from the surface. You might need several different widths, but 3/4" is a good all-round tape. For places where there is a line between the paint and something else that is very visible, use Fine Line Tape (the green stuff). It is expensive, but cuts the paint when you remove it. You'll need several rolls of tape (like five at $2.75 each). Masking Paper - You can buy special paint masking paper, but I utilized regular newspaper the last two paint jobs and it worked fine. Best of all, it is free. Tack Cloth - One tack cloth is a good idea to use between the primer and paint step and between the paint and clear step (see below). This removes any particles that might of landed on the finish while drying. This is $1.29 each. Rags - Old cotton t-shirts will work. You need something to help you clean-up the mess you make while painting. Plastic - If you have access to a paint booth - great. If you are like me, it was the garage. Here is a very important rule to remember - if you don't want it painted, cover it. Paint goes everywhere in your garage. Cover the floor and all the walls. Get cheapo $3 plastic paint drop cloths and staple or tape them in place. You'll need about six of the big ones. If you want to re-use them later, get the heavy duty ones (they are about three times the cost). If you paint in your garage, assume you will get some dust and bug imperfections in the paint. I have found this unavoidable in the past. Note that in some locations, it is illegal to paint your vehicle outside or in your garage. Wax and Grease Remover - Ahhh - DX-330. This stuff is great if you have tar or something you need to remove from you vehicle. It is required that you use this stuff prior to painting the final surface to remove finger prints, wax, etc. Failure to do so will result in problems (like primer and paint not sticking). A gallon of this run something like $30 (?). Thinner - You use standard thinner to clean everything up at each stage. A gallon of this run around $17. You will need at least a gallon. I used DTL-876 here. Fans - Ventilation is key. You need at least one, and I would recommend multiple box fans taking air (and paint fumes) out of the garage. I utilized three fans my last time and this was a good amount in my opinion. PROCEDURE Step 1 - Remove all the parts of the vehicle that can be removed. This includes windshield wipers, chrome, bumpers, etc. I find it easier to strip the vehicle than tape everything up. If you remove it - it clearly cannot get painted. Some things like tires I just cover up because it is a pain to remove them. This step could take up to half a day. Before you do this step you might want to take a "before picture". Step 2 - Prepare the body. If you have any body work to do, now is the time to do it. I cannot comment too much on rust prevention and body work, as I have had minimal amounts to do and these topics could double the size of this. Suffice it to say that if your existing paint is still there, it is useable. Scuff it up with 220 on the D/A and it will be fine. Be care not to break into the old primer (but it is ok if you do) and be super careful not to break into bare metal. If you do, you must metal etch (another chemical) the metal and then immediately cover it with primer so that it does not start rusting. If you are doing body work, you probably want a special primer which builds layers, so that they can then be sanded down again to make everyting flat. This is a different primer than I will talk about below. The primer below simply covers and seals the existing surface and provides a good surface for the paint to stick to. I hate sanding. However, this is the most critical step of all the steps that follow. If the body is not PERFECTLY straight now, it certainly will not be after the paint is laid. In fact, any minor imperfections here will be exaggerated when the paint and clear are laid. Follow the cardinal rule - take your time at this step. Plan on spending at least one day on this step. Use wet/dry sand paper and do your sanding when the vehicle is wet. It is easier this way and actually cleaner. Step 3 - Clean off the surface with wax and grease remover. Step 4 - Mask everything you don't want painted. This is an art. Use plenty of masking tape and paper and cover everything and don't leave any piece of paper "flapping in the wind". At this time you can cover everything in the garage too. Step 5 - Clean off the surface again with wax and grease remover. You can also use the tack cloth at this point if you desire. Start the fans in the garage. You should do this whenever you mix or paint. Step 6 - Mix the primer and catalyst as directed on the primer can. In my case, this was 1 part primer to one part catalyst. Depending on the catalyst, you might have to let it sit for 30 minutes to mix properly. Make sure you use the strainer when pouring into the can and use the stir sticks to mix everything real good. Before you even open the primer and catlyst, shake them up well. Use gloves and the mask. You should do this whenever you mix or paint. Step 7 - Test the spray gun on some newspaper. Get the pattern down properly before starting. This should be done before the primer, sealer, paint and clear coat steps. Step 8 - Spray a light coat of primer on the vehicle. Hold the spray gun about 16 inches away from the vehicle at all times and move in long, flat strokes the length of the car. Start on the left, start moving, press the spray button, keep moving, release the spray button when at the right, stop moving. The next stroke should slightly over lap the last stroke by 25%. Spray a very light stroke to start with - it doesn't take much. Oh, I believe you lay the primer at 50 psi, but check the instructions on the primer. Don't lay it any higher or lower than this, as you can get fish eyes, orange peel, etc. Primer dries fairly quickly (like in 15 minutes). It is good to put on two or three coats, but no more. If you put too much on, it can crack over time (you don't want too much surface). Lay each coat about 15 minutes apart. Undoubtly you will have a run or two. No problem. Let the primer dry longer in this case - like two hours. Then get out your hand sanding block and some 250 or 400 grit wet/dry sand paper and sand the run out. Use water when doing this. Make sure the run is perfectly flat with the rest of the primer. Clean everything with wax and grease remover and then the tack cloth and if necessary, lay a little primer over the spot. Your last coat of the two or three primer coats should be a sealer coat. You can buy special sealer products, but simply adding in some DTL-876 thinner to the primer and catalyst will seal the surface. Mix 1 quart primer to 1 quart catalyst to 1 pint thinner. Again follow the instructions on the can and lay it just like above, except at about 45 psi. Let this dry 30 minutes minimum. You should plan on spending four hours doing this step - more if you make a lot of mistakes. Primer is waterproof, so you could stop here if you wanted. However, it is best to lay the paint within a week of laying the primer (and you can start laying the paint after the sealer dries, but I perfer to let it thoroughly dry overnight just to be safe). When done, clean all the equipment with thinner. Put mixed but unused primer/catalyst in a gallon jug or something that can be properly disposed of later. Close unused primer and catalyst tightly. Be sure to clean the gun and can very good; failure to do so could contanminate the next paint step. Step 9 - Paint time. You lay the paint at about 55 psi. The paint should be thoroughly mixed-up prior to opening the can. Mix the paint by instructions. This usually means 16 parts paint to 12 parts reducer (matched to the current temperature) and 1 part hardener. Use the strainer and stir sticks. You shouldn't have to let this sit at all. Make sure you use your mask and gloves. Clean the vehicle with the tack cloth prior to laying the paint. Lay three coats of paint. Let each coat dry at least 30 minutes before laying the next coat. Use the same back and forth method as with the primer above. A note about hard to reach spots. Expert painters will do door jams, under the hood and other hard to reach places first, so that they are out of the way. This is a good practice. I would recommend doing these first, letting them dry, then closing them so that you can paint the outside of the vehicle all at once and without the problems of being a gymnist. As with the primer, if you have a run, let it completely dry before attempting to fix it. For the paint, this means several hours and probably over night. Use 400 grit sand paper, again using water. Don't use the D/A after the primer step - this is a hand sand thing. If you are ever scared about using a particular grit, go up one grit and start there. 400 grit for color sanding paint is appropriate however. When complete, clean the gun and can. Dispose of unused paint/hardener/reducer in the proper place. Close-up all cans. In general the hardener needs to be used in seven days or it goes bay (so the can says - I've used it months later, but you gotta seal the can well and then you'll have to use plyers to get the lid off again). Let the paint dry over night before laying the optional clear coat. Step 10 - Clear coat. As mentioned above, this is an optional step. A urethane clear coat will greatly increase the durability of the paint. Plus it will give it a bit of depth and gloss. Follow the instructions on the urethane clear coat can. Generally this stuff is mixed with some hardener. You mix it in the can (with the strainer) and then spray it. You mix 1 gallon of urethane to 8 oz. of hardener. Use a tack cloth on the vehicle prior to doing this step to remove any minor particles that landed on the vehicle while it dried over night. Like the primer and paint, lay the clear coat very lightly at first. However, and this is an experience thing, you gotta lay it somewhat heavy and wet. Be careful not to let it run though, because fixing a clear is, well, undesireable and difficult. Use the same back and forth strokes, overlapping with the last stroke. The directions call for 45 psi, but I like it wet, so I used 55 psi. You can lay several coats of clear. A gallon should allow about three coats on a full sized vehicle. Let each coat dry around 15-20 minutes. When done, clean all the equipment and properly dispose of any excess. Let the finished product dry overnight. Step 11 - Remove all masking tape and paper. Be careful during this step. The excitement of "seeing the final product" can cause you to tear away masking tape too quickly and tear the paint away from the surface. It will take a couple of days for the paint to fully dry and cure. Step 12 - Replace all the bolt-on pieces that were removed. Again, don't get too anxious so that you scratch your work of art. Step 13 - Smile - you are done! Quick, take some pictures before it gets dirty! If you plan everything right, you can strip the vehicle one night, do the body work at your leisure (you can even do some body work without stripping anything), lay the primer Friday evening, lay the paint on Saturday and the clear on Sunday. You can put it all back together on Monday night and drive it Tuesday. But remember the cardinal rule - take your time. The more time you take, the better the end result. PPG provides data sheets on all their products. Get these prior to purchasing anything. They explain a lot of things such as:
PPG also has a full-line catalog that comes highly recommended. See if you can't grab a copy of that before starting too. And just for reference, a typical spray can holds 1 quart of material. While the primer, paint and clear all have instructions on mixing, rarely do they have a nice fomula that comes exactly to a quart. You are gonna have to do some estimating and that's ok because you don't have to exact. You remember this from grade school, but here it is anyway:
SOME PAST EXPERIENCES Undoubtly you will have some mishaps your first time. My biggest problem the first time was I either didn't use the right temperature reducer or laid the paint at too high a psi. This caused what is known as an orange peel effect - kinda a texture in the paint like an orange. Color sanding helped this a bit, but it was never perfect. I also learned that anything you didn't want covered with paint in the garage better be covered by plastic. Expect your shoes, clothes and fans to be a different color than when you started. My second paint job was a fender fix. While I laid the paint great, I didn't do a good job of masking. It is important to mask along natural lines of the car. I should of repainted the entire hood and fender instead of attempting to just do the area I fixed. I'll know better next time. My latest job was my full-sized Blazer. My biggest flaw here was body work. I should of spent more time doing this terrible task. Althought the paint went on pretty good, it highlights the body work flaws. I also should of painted the hard areas first (under the hood, door jams) and then painted the outside. I tried to do everything at once and this cause me some problems in the form of runs (the hood was half up and hard to get to for example). Each time however, I have improved, and I have always been happy with the end result. It is always a vast improvement over what I started with. CONCLUSION I'm sure I have forgotten or left out several items. If you have any questions while reading this, please don't hesitate to drop me an email message and I'll do my best to help. Three other sources of great information are (1) various 4x4 magazines, (2) your local library and various books on how to paint and (3) your local auto paint supplier. I relied heavily on the the latter and found they were very knowledgeable and helpful. They took a lot of time trying to help me do the right job. If your supplier isn't - find another one. I didn't add up all the finishing products and miscellaneous products above, but not counting the compressor and tools, you can paint a full-sized vehicle for around $350. This compared to some quotes I recently got in the $1000 to $1500 range for similar paint jobs. Enjoy - and let's see those before and after pictures when you are done! Rick D. Anderson (ricka@mdhost.cse.tek.com)
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