Your Auto Painting Questions AnsweredThis page is jam-packed full of extremely valuable car painting tips and steps on how to paint a car in answer to your auto painting related questions. All answers are given by our resident auto painting industry expert Dave Gage, Car Cosmetics . A good number of topics have been covered for your convenience such as how to setup a paint spray gun, applying clear coat, auto paint mixing and heaps more important steps on how to paint a car. Each topic has been categorized clearly to make it easy for you to navigate your way through this page. Our Topic Areas
1. Paint Spray Gun
Related 1. Paint Spray Gun RelatedQuestion: I'm new to working with water-based paints, could you tell me what I need to use to clean my gun with after use? Answer: Quite simply, to clean your gun after using water-based paints use clean tap-water. Question: I'd like to learn more about which paint spray gun to use. The guns I have are dev620/dev670, my 620 I use to spray on base coats and my 670 to spray on clear coats and single-stage. In your opinion, which is the better gun to use SATAjet or DeVilbiss? Answer: As for which spray guns are the best, well that's not really a question we can answer easily. Both makes are excellent and do what they are designed to do. However, there are many professional painters who favor one over the other, not really for any other reason than for the feel of it. I (Dave Gage) have used both and I really favor DeVilbiss, only because of the weight, balance and feel. Both makes of spray guns are in the global top 5 and are renown worldwide for there reliability and excellent construction. In addition, both guns are proven in the motoring world. So to re-cap, it's a matter of personal choice when choosing a paint spray gun. We suggest you try both makes and choose the one that feels right for you. Don't make the mistake of choosing the paint spray gun that looks the best or costs more/less; when painting cars the paint spray gun you choose will become an extension of your arm, so like a pair of shoes it needs to feel and fit just right. Question: My vehicle surface is clean, smooth and ready to go. I have an FX300 paint spray gun from Sharpe. It says to run it at about 29 psi at the gun. I have a 3.5 hp compressor with a 60 gallon capacity. The cfm (cubic feet per minute) is 15.8. I have a moisture filter at the gun and one at the tank. I also have a pressure gage at the gun. I'm running about 50ft of 3/8 inch hose to the gun. I need this due to the distance from the truck. I may have in the past had too wide of a fan spray, about 9 inches. Also in the past, due to not understanding what I was doing, I was about 5 inches away from my material, trying to keep the material going on wet and thinking each coat had to be glassy smooth, which then created too much material going on too fast and therefore paint runs. I believe I've learned that the first coat doesn't have to be glassy smooth, but clean. Second coat goes on when the first coat is tacky but not sticky and the third coat goes on? Any imperfections can be sanded and buffed out. I thought the 3rd coat was to be PERFECT? My spray
temp has been between 70 degrees Fahrenheit and 80 degrees
Fahrenheit. Humidity? I did a test on an old hood I have and it was better, but like I say it wouldn't lay down. I still have little bumps, not orange peel, but little bumps. At this point any other tips you can email my way would be appreciated. Answer: What we recommend is as follows: Generally speaking if you are using a conventional type of spray gun you ideally need a constant pressure of around 70 psi, anything lower and you risk applying the paint too thick/too heavy, hence the surface imperfections: lumpy/bumpy appearance. Our best advice would be to upgrade your compressor. Although you're using a compressor with a 60 gallon capacity tank with a cfm of 15.8, most conventional spray guns need up to around 19 cfm. HP (horsepower) isn't really an issue in your case. You say that it tells you to run it at about 29 psi, however this is dependent on the type of material you are spraying, 29 psi does seem rather low. We currently use 2.5 bar which equates to around 37.5 psi (1 bar = 15 psi.) Question: I would like to know more about the different kinds of automotive paint spray guns, how to setup a paint spray gun and how to use a paint spray gun correctly? Answer: The following car painting tips are very valuable as this is an important part of auto painting to understand and get right. Our best advice to learn how to use an automotive paint spray gun would be to watch How to Paint a Car - The System (Part 1 & 2). This shows auto painting professionals demonstrating on-screen how to correctly use paint spray guns, especially in relation to the surface being painted. This is extremely important if you want to achieve a uniform paint finish. Paint companies recommend specific paint spray gun setups for applying their products with. This would indicate a specific fluid tip and air cap that should be used with the particular paint product that would be available from the dealer of the paint spray gun. This is a great reason why you should purchase your paint spray gun from a paint supply store instead of from a tool store that sells a variety of tools without servicing any of them. These settings are available from information sheets and application guidelines or from your auto paint supply store worker. For further information on how to setup a paint spray gun, please refer to 'How to Paint a Car - The Written Guide'. For risk of repeating ourselves, we recommend you take a look at our "Auto Painting Tips" newsletter archive and issues 02 03 on Paint Spray Guns. In there we talk about HVLP spray guns (High Volume Low Pressure), different types of paint spray guns, what you must consider when purchasing a paint spray gun, how to thoroughly clean a paint spray gun and paint spray gun manoeuvrability. You will also find information in those issues about why purchasing an expensive, top quality HVLP paint spray gun will more than pay for itself in just a few paint jobs; saving you money overall. Question: What car painting tips do you have regarding the use of hardener & thinner when spraying auto paint primer through a paint spray gun? Answer: It depends on which type of auto paint primer you use. If 2k auto paint primer is used then hardener should be used, if it's air dry auto paint primer then thinner should be used. Question: Do you have any data on what types of paint spray guns I should use for base coat clear coat application and auto paint primer? Any info on the correct PSI settings and spray fan settings? Answer: Various countries use different types/makes of paint spray guns, here in the UK we generally use either (SATA or DeVilbiss GTI's). As for the setup, well there are many types dependent on what types of paint you are using. Again here in the UK, most auto body shops only use water-based paints and HS lacquers. Try speaking to your local auto paint supply store and asking them the same question for a second opinion.
2. Clear Coat RelatedQuestion: My dark blue 1994 Honda has peeling clear coat on the bonnet and roof. To respray, does all the clear coat have to be removed? I propose to give it a good wet sand, followed by a primer to aid adhesion and coverage of minor scratches and bare bits, base coat and new clear coat. Answer: Yes, the way to do it is to flat (sand) the peeling clear coat back (so no more peeling is evident), then apply a light coat of primer (x2) should be enough. Then when fully dry apply 2 to 3 coats of base color. Then when dry, lacquer the full area with 2 coats of clear coat. Question: The lacquer/clear coat finish I have is shinier than my first attempt but still not perfect. Would using a rubbing compound improve the situation or would I be wasting my time? If you think I should try buffing it up what product would you recommend? Answer: Indeed buffing the lacquer would improve the gloss finish. We recommend that you use a fine grade wet and dry flatting (sand) paper first. Lightly flat (sand) the lacquered panel with 1500-grit wet and dry paper, then use Farecla rubbing compound. Apply a small amount to the panel and use a machine polisher to gently polish the panel with. Once happy with the finish, hand polish the panel and use a quality wax polish i.e. Autoglym super resin polish, this will seal and protect the finished panel. Question: I have a motorcycle and I decided to change the color. I didn’t use any finishing coat or top coat. Will the color of my motorcycle look shinier if I use a top coat or a finishing coat? Do I have to use sandpaper before I apply the finishing coat? What grade of sandpaper should I use? Answer: The panels of the motorcycle should be flatted down using 1,500-grit wet and dry sandpaper. The color you then wish to apply will of course now be done so over a newly flatted (sanded) surface. Approximately between 3-5 coats of color may be applied to the panels. Then up to 3 coats of clear coat/lacquer. This would indeed give the finish that showroom shine. Base coat isn't shiny but matte in appearance, the glossy shine comes from the lacquer. Question: Using the methods outlined in your video I successfully prepared, primed and base coated the areas which required attention. However I have not as yet mastered the application of the finishing lacquer coats. The finish is OK but is more of a matte finish than a clear gloss. What if anything would you think I had failed to do? Answer: There is no set defined method of painting. Many painters employ various methods of applying lacquer/clear coats. To achieve optimum results when applying base coats and clear coats, it should be carried out in a warm, environment, a temperature of at the very least 22 degrees C, with plenty of ventilation and sheltered from the elements. Paint does not respond well to temperatures below 22 degrees C. Also, when applying lacquer, be careful not to apply too much, too soon. Apply one coat, leave between 5-15 minutes before applying your second coat. Once the second coat has been applied, if the finish is shiny/glossy at that point, do not apply any more lacquer. It is not a case of the more you apply, the shinier the finish becomes, it doesn't work like that. Question: My car color is white, I need to re-paint it the same color. Please let me know if I could use a clear coat to finish the job so I can get a better gloss on my white car or can I mix clear coat with the final coat of white paint? Is it true if I use clear coat on my white color car it will change color after some time? Answer: If you use a clear lacquer over the top of white 2 pack gloss/solid, depending on the make and quality of the clear coat/lacquer, it may well discolor (go yellow in appearance). This is largely due to the pigment in the clear coat, although lacquer is almost clear, it is in fact opaque, with a yellow tinge. You would clearly see this by emptying a gallon of lacquer into a clear plastic container and holding it up to the light, easily seeing the color difference. Always remember that you get what you pay for with auto painting. If you spent just $58 on a gallon of lacquer don't complain if the color looks off after so long a period, whereas if you spent $580+ for a gallon of lacquer, the end result would have much more longevity if it would ever degrade at all. Think of white 2 pack gloss as a colored lacquer (paint+lacquer), there would be no sense in applying a further coat of clear lacquer to a coat of colored lacquer which is essentially what white 2 pack gloss is - white lacquer. Our advice, would be to paint the vehicle in a white base coat then use a clear coat for that showroom shine. The purpose of using a base coat clear coat application is that the base coat will compensate the risk of de-coloration from the lacquer, it would do this by being brighter from the onset. Some issues with 2 pack gloss paint are related to heavy metal content which is considered unsafe for the environment. Question: Is there a way to safely remove peeling clear coat from undamaged paintwork underneath? Answer: The answer to this question is no, not really. The clear coat binds itself to the undercoat color. Peeling is usually a sign that poor quality materials have been used to paint the car with.
3. Auto Paint MixingQuestion: I don't understand the thinning out recommendations on paint products, can you give me a simple form for etch, clear and base coats for 500mls? Answer: Thinning for different types of paint
products requires different amounts. The general rule of thumb
with solvent based
paint products is as follows: Question: We are doing our first paint job on a small
project. For the primer (Tintable Polyurethane) we bought the
tint. Answer: Firstly, the ratios to which you mix any paint are relative. i.e if the ratio is 5:1, then this indicates 5 parts of paint to 1 part of hardener/thinner/catalyst. So in broad terms the ratio should always be the same. For example:
The same
rule applies for a ratio of 3:1 - 3 parts paint to 1 part
hardener/thinner/catalyst. So to mix 3 liters of paint, you
would add 1 liter of hardener/thinner/catalyst. Question: How do you mix the base coat and the clear coat? Also, I wanted to put flake into it. What is the best way to do that? Answer: Dependent on the manufacturer and make of paint, generally speaking, base coat is mixed 2:1 (using a 2k base product of solvent base.) Which means 2 parts paint : 1 part thinner should be applied. Lacquers: using a MS (medium solid) system lacquer, again should be 2:1 - 2 parts lacquer/clear coat : 1 part hardener plus depending on the environmental temperature anywhere between 5-10% of thinners. We covered metallic paint in "Auto Painting Tips" issue 27. Question: I would like to know how to mix car paint so I can use it in my spray gun, including how much thinner & hardener should I use? Answer: You see, it really depends on what type of paint you are using. If it is a 2 pack type paint then you would generally use 2 parts paint to 1 part hardener, with a touch of thinner, usually 10%. So the rule of thumb would be a ratio of 100:50:10 of paint:hardener:thinner respectively. The best car painting tips we can give you on this topic with paint mixing being a systematic process, is that if you prepare the surface of your vehicle properly, mix all products correctly and apply them correctly, you will be left with an excellent paint job. The proper paint mixing ratios are included with product information sheets. Calibrated mixing cups and measuring sticks are available at your auto paint and supply store. If you are ever in any doubt, simply ask for advice from a member of staff who you bought your paint from, it is their job to guide you accurately. Color shade paint mixing on the other hand is really a job you should leave to the full-time professionals. They will follow stock vehicle color codes or codes attained from paint chip catalogues. This service they provide forms part of the paint system you purchase. Question: I've got hold of a 2 HP (horsepower) compressor and I've picked up a Big Gazebo, (both were cheap as finance is a major problem). The thing I'd like to know is: a) How to Mix the Paint? What ratio of paint to thinner? b) Can I get away with buying different makes of paint, thinner, auto paint primer and clear coat from somewhere like eBay? What are the associated risks? c) How Much Paint Primer, Color, Clear Coat will I need to paint my Alfa Romeo 156? How would I find this out? Answer: For part a) please refer to our answers previously given on auto paint mixing. There are many risks associated with paint mixing the various types/makes of paints. The best advice would be to buy all from the same manufacturer, as part of the same paint system. The better quality paint products that you use the more desirable and durable the end result will become. As for the quantity, this depends on the color and condition of the existing paint finish. A safe rule would be to always buy more than you require, the supplier you purchase the paint materials from will be able to guide you, it's their job.
4. Welding & Preparation for PaintQuestion: I'm currently buying a XB Falcon ute with a considerable amount of rust. What I want to do is cut it out and replace it with rust repair panels. I can use a mig or a tig but which one would be the preferred welder? Then after that, I would like to know how to get to the final part of painting, that is the step by step process for stripping and getting the car ready for paint. I'm going to be leaving the ute in the same color, so do I have to rub back the whole ute or can I wash it and then paint straight over the top of the old paint? Answer: Use mig welding to weld in the rust repair panels and as for the paint work, wash the car using a strong detergent, DO NOT WASH AND WAX! Primer and paint will not stick to dirt, wax, or grease. This is why you will have to take your time to remove all such debris from the surface of the vehicle being repaired using wax and grease remover. This will leave the surface as clean as possible. You will need to be meticulous in this area. It is important you do this after you wash the vehicle, before you sand it, after you sand it and between undercoats and top coats. Remember that each paint system will come with its own recommended products. Then flat the old paint work using 800-grit wet and dry flatting paper before applying the new paint. Question: I currently have a maroon red Honda Civic hatchback and wish to spray it blue do you have any advice? I was also wondering about surface prep, the paint is already in good condition and I want to remove it, how deep do I have to sand it down? Answer: You really don't have to remove the paint, no need to make unnecessary work for yourself. The original paint work needs to be lightly sanded, using 800-grit wet and dry sandpaper, this will provide a sufficient base for new layers to bond to. Any repair work should be carried out, only prime the areas that require it, then apply the new color. 5. Auto Paint Chemistry - Acrylic Lacquer/Enamel.Question: Please explain to me the difference between Acrylic Lacquer and Acrylic Enamel. Answer: For all intents and purposes, the use of lacquers and enamels in automotive painting is obsolete. Alkyd (natural-based) and acrylic (plastic-based) enamels dry by evaporation of the reducers first and then by oxidation of the resin or binder. The result here is that the paint finish may appear to dry quickly through evaporation of its solvent base however, the material continues to harden as resins combine with oxygen in the air. This is why infra-red lamps were used; the heat from them would speed up this process. During this curing process, a dry synthetic film would solidify over the top of the finish to offer a tough, shiny color coat. Wet sanding this coat to remove bits of dirt or debris would destroy that film and require touch-up painting to repair the surface blemishes. When compared to the durability of Urethane products, alkyd and acrylic enamels fall way short. Although they can cover in just one or two coats they cannot hold up to the same kind of harsh environments. In addition, the application of any lacquer based product over enamel would result in surface wrinkling . This is because the materials in enamel cannot hold up to the strong chemicals in lacquer. A special sealer has to be applied first to prevent lacquer solvents from penetrating and ruining enamel bases. Acrylic Lacquer has been a favorite paint among auto enthusiasts for years. It is easy to mix, can be applied at relatively low pressures, dries quickly and can generally be repaired and re-coated within 10 to 20 minutes after the last coat has been sprayed making it popular with custom car painters. Lacquer requires a number of coats to achieve color and coverage expectations. Then coats of clear lacquer are sprayed over color bases for protection and for required buffing. To buff lacquer color coats you would affect the color tint. This is why clear coats are applied so that buffing shines them to a showroom finish without disturbing the underlying color base. Due to the amount of Volatile Organic Compounds (VOCs) emitted by lacquer solvents, regulatory agencies minimized the use of lacquer paint or required that it only be sprayed in down-draft paint spray booths equipped with special filters and air-purifying systems. This is a factor to consider if you're contemplating a complete paint job for your car. If you are using Acrylic Enamel or Lacquer then we recommend you consult an auto paint supply store member of staff for advice and recommendations that apply to your specific need. Question: I have a 1974 Challenger that currently is painted enamel red, underneath is the original b5 blue metallic enamel. Is there anyway to paint this with lacquer without taking it to bare metal to do so? Answer: If the enamel is a synthetic based product then you can't apply 2k clear coat over the top, it will cause crazing. 6. Surface ImperfectionsQuestions: For two years I’ve worked with SPIES HECKER PERMAHID water based paint and I have one problem: On the light colors (EXL from Peugeot) or silver color, the base coat always dries spotted (cloudy). I try more or less base coat reducer, low or high pressure, two full coats and dry coats, dry between coat and still no joy! Maybe you could tell me where the problem lies because I ask the technicians from Spies Hecker and they say this is not possible. With Dupont or Autocolor I don’t have this problem. Answer: Spotting/clouding in light colours i.e. silvers/blues etc. is largely due to low temperatures during application and damp conditions. Firstly, when applying the base coat colour, apply one light coat first, followed by 2 full coats as soon as the first coat is dry (do not allow the second and third coat to dry in between). Then when dry, tack cloth clean the surface before applying the drop coat, usually 1 to 2 drop coats. Ensure the base coat is fully cured before applying clear coat. TIP: Water based paints respond better to infra-red curing rather than low bake or by using compressed air being blown onto the surface. Question: I recently painted some areas on my car that had scratches on them. I noticed that one of the areas I painted I could still see sandpaper scratches under the paint. How can I correct this? Answer: Scratches under the base coat are a result of poor preparation. To rectify this, the area should be flatted down (sanded) with 800-grit wet and dry sandpaper, then apply 2 coats of 2k primer. When dry, wet flat with 800-grit wet and dry paper once again, then apply 2 to 3 coats of base coat, then lacquer. Question: I would like to know what causes edge mapping (when primer edge can be seen under dry paint) and how this can be stopped? Answer: Mapping is caused by a couple of
things: Question: I have a 1988 Honda Shadow VLX 600 with
metal fenders and gas tank, other pieces are
plastic. Answer: It sounds like the paint products you're
using are incompatible with each other, hence the unwanted
reactions you're experiencing. Make sure that the paint
products being used are fully compatible and are part of the
same paint system, ALWAYS! We also suggest using 2k products
only. Question: The hardener I was working with hardened at the bottom of my spray container, the effect was an orange peel texture after applying the mixture. My remedy was to decrease the paint flow volume and increase air pressure. Was I right in doing this to eliminate the orange peel effect? As far as the hardener problem, I mixed the two for a longer period but then would get tiny clumps sprayed out of my spray gun nozzle. Poor cleaning of the spray gun perhaps? Please advise. Answer: When paint mixing any 2pack component, it is essential the two components are mixed thoroughly. Depending on the air temperature, it may well have to be applied fairly quickly (usually within the hour), an ideal temperature would be around 22.5 degrees C. Then the spray gun should be emptied and cleaned out straight away to avoid the epoxy drying in the spray gun. Orange Peel is usually down to a combination of faults. Please refer to our Auto Paint Repair section on Orange Peel for a detailed breakdown of the surface condition, causes, preventions and solutions. Question: Thanks for your expertise. I am learning a lot and I feel my project ('97 Ford F150 GT) will be a great success with your support. However, I have painted a few work trucks and though my preparation work on the bodies has been thorough, my application of the paint has left me with a lot of wet sanding. There has been a pin hole like orange peel effect and even after wet sanding for hours on end I still get little pin holes. Most people don't see it but I can and it is unacceptable to me. I want my truck to be a show stopper! Any advice? Answer: Please refer to our Auto Paint Repair section on Orange Peel for a detailed breakdown of the surface condition, causes, preventions and solutions. As for pinholes, this is usually caused by too much clear coat being applied, again 2-3 coats is all that should be required. Specific lacquer and urethane paint finishes can be wet sanded and polished to remove nibs, flatten orange peel and smooth out blemishes. This work is normally carried out on clear coats instead of on actual color coats and may require additional light applications of clear afterwards. This is why professionals will rarely remove the masking from a vehicle until they are pleased with the entire paint job and are sure that they have taken care of all imperfections. 7. Automotive PaintQuestion: I wish to paint my 1987 Corvette flat
black, it’s currently in gloss black. No body work is needed
and all trim will get the flat black treatment. Answer: Flat the car with 800-grit wet and dry,
mask the car then apply 2 to 3 coats of 2k matte or satin
finish black. Providing there are no imperfections or problems
then no further work will be required. Question: I have a query about the water-based paints that are on the market. Are they more expensive than the other paints or are they cheaper? Usually I was buying a liter of paint for under £20, could you tell me roughly how much these new paints are going to set me back? Answer: Indeed water-based paints are much more expensive and depending on the product make, you could be spending anywhere between £45 to £90 per liter in the UK market. Question: I have a question about the new water-based paints that are now available because cellulose has been taken off the shelves. Can you tell me more about this new paint and is it better or worse than cellulose because I used cellulose a lot and I don't really know much about this new paint. I've done a lot of research on water-based paints and I find people have mixed feelings. What do you guys think of this new system? Answer: Indeed there are a lot of mixed feelings out there with regards to water-based paints. Modern paint technology is far superior than many people think. Mixed
feelings are a result of new technology vs. old mind-set, i.e.
many professional vehicle painters are not welcoming of change,
and because they don't fully understand water-based paints,
they don't like using them. It's hard to teach an old dog new
tricks! Question: I have primed my car with 2k-beige primer and at the moment it is sat there rubbed down to a 1500-grit sandpaper finish. I rubbed it down in stages from 600-, 800- onto 1500-grit. I have checked it over and over for any imperfections and all is well. I bought midnight blue paint and was told to just mix it 50:50 with 2k thinner without any hardener. The car has been prepared including back of doors, door wells and the back of the boot and bonnet. I was told that 5 liters of ready to apply paint would be enough, is this true or would you advise me to buy a bit more to be sure? Also, I am unsure of the room temperature the 2k paint has to be applied to the car in, is it about 60 degrees Fahrenheit? I just need to know a bit more about the base coat/room temperatures/how long you leave the paint to dry between coats? Please could you give some more advice on the stages that come after the car has been primed? Answer: 50:50 is the right paint mixing ratio for 2k base coat. As for the quantity of paint needed, this will usually always depend on the opacity of the color being applied. For example, when covering a light colored primer, you will need to use more of a dark color (midnight blue) than a lighter color, due to the high contrast between the two. Painting yellow or a similar light color over a light colored primer will generally require less paint. The same rule applies when working with darker colors; if you use a dark colored primer such as dark gray, then less dark colored base coat will be required. Discuss this with your auto paint supplier, they will advise you according to your budget, on the best paint set-up for your project. As for temperatures, the panel temperature should be around 25 degrees C with paint applied in a dry atmosphere. The ambient temperature should also be around 25 degrees C, drying times between coats should be around 5 to 10 minutes. Don't forget that 2k base coat is only a color and will require 2k clear coat lacquer over the top. A correct base coat clear coat application will always give you a top coat with a glossy showroom finish. Usually 2-3 coats of lacquer is all that will be required. 8. Painting Vehicle Accessories - Front Bar CoverQuestion: I'm painting a VN and have purchased a new front bar cover. I have wet sanded it using 400-grit sandpaper and then cleaned it using wax and grease remover. The problem is I can't get the paint to sick to it! I'm also having trouble with fry ups in the paint, is that because the temperature is too cold or because the surface is not clean enough before painting? Answer: Firstly, establish what the the cover is made from. If it is a plastic type material, it will require an adhesion promoter. This is a special type of plastic primer, which should be used once the cover has been flatted down and cleaned using wax & grease remover. Usually this product can be purchased in aerosol form with 2 coats needed at room temperature, 25 degrees C. Then a 2k primer should be applied over the cover, 2 coats will be enough. If the cover is to air dry, leave it for at least 24 hrs. at room temp. Then wet flat using 800-grit wet and dry flatting paper. Apply the color in light even coats leaving 5 to 10 minutes between coats. Don't try to apply too much color with the first application, this is usually the cause of cracking or crazing. Usually 2 to 3 coats of color will be enough, dry for around 30 minutes at 25 degrees C, then 2 to 3 coats of clear lacquer should be applied. Again light even coats leaving 10 to 15 minutes in between. Leave to dry again for around 24 hrs at room temp. 9. Paint Brand RecommendationsQuestion: Here in the United States there is PPG paint and Dupont paint including several others. What brand do you recommend? Answer: To be fair and honest, both brands are very good and there is very little difference between them both. In terms of overall paint quality, there isn't much in the way of poor quality in use nowadays. 10. Special Effect Additives – Pearl, Metallic.Question: I painted my car with metallic paint 2 months ago and now I can see some small scratches which I patched beforehand. In addition, the shine of my clear coat is a little down. Please help. Answer: The scratches have appeared largely due to poor preparation before the metallic paint was applied. Best advice, re-flat the area using 1,500-2,000 grit sandpaper (wet and dry), using 2-3 coats re-apply your metallic color, being extra careful not to apply too much. Once the base coat has dried (cured) apply up to 3-4 coats of clear coat/lacquer. If it is an air dry product that is being used, leave for up to 24-48 hours to cure properly before you commence polishing. This would then restore the gloss finish. Question: I find your "Auto Painting Tips" newsletters very interesting and helpful. I'm doing up my Fiat Punto as it's in desperate need of a re-spray. This will be my first time spray painting. I was going to spray my car so that it changes color when you walk around it but thought it would be too hard for a first timer so I've decided to spray it black and put red and blue speckle bits into it. Do I put these into the paint or lacquer? Also could you give me any advice on the best way to go about it and what amounts of paint I would need, etc.? Answer: You will need to introduce a pearl stage into your base coat clear coat application. Firstly, purchase around 3 liters of black 2k base coat. Then 0.5 liter of red pearl and 0.5 liter of blue pearl. After applying all the black base coat, apply 2 very light coats of both pearls, then 2-3 coats of clear coat. 11. Dealing with RustQuestion: I understand that rust removal can be performed with a chemical stripper. This is new to me and I was wondering if you could give me the name of this product and whereabouts I might be able to purchase it? Answer: You can of course use a chemical stripper to cure rust however, this is not the method that we favor the most. The easiest and most professional method, that indeed an auto body shop would use and indeed any home auto painter, would be rust removal by sanding. However, if you want to use a chemical stripper, there are various products on the market and indeed worldwide. The most popular product is Jenolite. Jenolite can be bought from most auto paint supply stores. How does Jenolite work? First, thoroughly clean the infected area, brush the solution on, then leave it to work on the rust (always following product guidelines.) You would then wipe the area down, removing the rust and then primer straight over the repaired area. Always bare in mind that rust is almost cancerous; it spreads once it has infected body work. Whilst most chemical strippers will remove it, this method is more of a retardant (makes the progress or growth of rust slower) than a total cure. The most secure way to get rid of rust is to quite simply cut out any infected areas and replace them with rust repair panels. However, this is not always possible depending on where the rust is located on the bodywork. If you cut the infected area out, there is absolutely no way it can come back unless a new case of rust develops elsewhere on the bodywork. Question: I want to fix some rust problems on my car, it has deep rust on the wheel-arch and kick plate area. I'm first going to remove the bulk of the rust using 80's grit paper, do I then need to apply some kind of etch primer, if so can I buy this in a can? Then, I apply the primer, let it flash off properly, then rub with 320-grit then 500-grit sandpaper? I masked up the area to protect from over-spray etc. from the top-coat and the etch and primer coats. How then do I apply the top-coat to achieve good blending in? Answer: Yes, you will need to apply etching primer to the panel, however this will only be needed if you sanded down to bare metal. If paint still remains on the surface then no etching primer will be needed. Yes, etching primer is available in an aerosol spray can. Gently apply the color coat in light and even coats, you only need to apply as much color as it takes to cover the repair/primer area. Then 2 coats of clear allowing 10 to 15 minutes in between coats. All else is correct. 12. Supporting Products - Primer, SealerQuestion: What is the difference between primer and sealer? Answer: Primers are materials that are applied over bare metal once the metal has been properly prepared. Their category comes under the different products that are separately designed to provide a variety of surface preparation functions. Together, they can be classed as undercoats: those materials applied to auto body surfaces in preparation for paint applications. These would also include:
Sealers A simplistic definition of sealer is that it forms a sort of barrier between the undercoat and top coat (paint). They really can be the difference between an adequate paint job and an excellent one. In providing a little more detail, the purpose of sealers is:
Question: What would cause primer to "curl" in certain places on the surface? I tried to prime my truck but the primer ended up not sticking at all and curled terribly. I could peel it off like a weird tape, what happened? Answer: The layer of primer is separating from the surface of the vehicle because of a lack of physical bonding. Checklist:
13. Applying Aerosol PaintQuestion: I would like some advice on how to go about spraying with aerosols - things like wing mirrors & spoiler fins. Also, the main problem with the paint work on my car are the scratches (through to primer) on most panels. A re-spray is out of the question. Any advice would be appreciated. Answer: Using aerosols to paint wing mirrors etc. is quite an easy task. The same rules apply whether you are using a spray gun or canned paint. First, make sure the repair area is clean from any dirt, dust and debris. Then, the surface to be painted MUST be flatted using 800-grit wet and dry paper also any damage such as chips, scratches etc. should be repaired. The surface should then be cleaned thoroughly and then primed before applying the color. As for scratches to the bodywork, unfortunately if these are deep enough, then a re-paint will be in order. 14. Working with FiberglassQuestion: I have put a pair of side skirts on my car but I have problem with them. After I had fitted them, I put a skim of filler over the top of them to hide the join. I sanded the filler down and primed and painted them but after a few weeks they had cracked along the join. Could you tell me why this is? What can I do to stop this happening again? Answer: We assume the kit is made from glass fiber? If this is so then the kit needs to be flatted (sanded) down with 80-grit paper then glass fiber should be applied over the joint (NOT BODY FILLER). Then flat (sand) down the glass fiber with 80-grit paper before applying the final coat of body filler. The reason it cracks with the use of filler is because the filler isn't flexible. Question: I’m painting a ‘07 Corvette fiberglass deck lid but having trouble getting the paint to stick correctly. What am I doing wrong, what should I do different? Answer: Fiberglass is a fairly easy product to work with and paint over. Firstly, ensure that the gel coat that features on the fiberglass surface is flatted (scuffed) correctly using 800-1000's grit wet and dry sandpaper. Making sure that you scuff absolutely all areas both hidden and obvious. Once you're finished flatting down the whole surface area, make sure that any imperfections on the lid are filled in using a 2k self-leveling polyester finishing putty. Once that is done, apply up to 3 coats of 2-pack high build primer. Once this is done, leave it to stand for 24 hours in an environment where temperatures are not going to go below 20 degrees C. Then flat (sand) down once again using 800-grit wet and dry sandpaper all over for a good key, i.e. so that the subsequent top coats are provided with plenty to adhere to without any further fear of these coats not sticking. Referring back to the 2k self-leveling polyester finishing putty, in the US, you will find this product referred to as Bondo or Rage. Question: I'm currently working on fixing a fiberglass body kit onto my car. On a basic level would you be able to give me some tips on preparing it? Also, what are the ratios for primer, paint and lacquer when it comes to adding the hardener and thinner? Answer: Fiberglass is easy material to work with. Firstly, make sure that the kit fits properly by running a trial fitting, any trimming should be done at this stage. Then any splits, cracks or pin holes should be filled. Then the kit needs to be flatted down ready to be primed. 2k primer should then be applied using 4 good coats, then flat down with 800-grit wet and dry paper before applying the color. As for the ratios this depends on make and type of paint. Your best bet would be to ask your paint supplier for a technical data sheet, this will give you the correct paint mixing ratios to use. 15. Custom Paint Finishing – Adding StripesQuestion: I’m unsure of the steps involved to
paint candy apple red paint. Answer: After laying down the black paint, when fully cured (if the finish is free of any dirt/dust/debris) gently scotch the surface with ultra fine grade scotch pads (like using ultra fine sandpaper). Then fully clean the surface with pre-clean panel wipe (solvent based cleaner). Then apply 3 to 4 coats of candy coats (no need to sand the color). When dry, apply 2 to 3 coats of clear coat. Question: I have a 2006 Ford Mustang GT and I would like to paint racing stripes on it. However, I'm unsure of the surface preparation that is required. What is involved and do I need to plan on clear coating the entire hood, top and trunk area? Answer: It really depends on the types of stripes being used. Ideally painting them on is the best way to do them. If you can lay out a pattern on your car with tape, you're halfway there. In this instance, it's not only fast and inexpensive compared to other types of custom painting, it's also easier to do yourself. You may wish to look at custom painted car magazines or visit custom painted car shows to gain a good source of ideas. Once you have a few designs in mind, try drawing on a sketch of the car. You'll be able to work out a lot of details that way and you may come up with a better way to enhance the effect. It is highly recommended that you use a base coat/clear coat paint system for your stripes. The original paint work needs to be lightly sanded where necessary, using 800-grit wet and dry sandpaper, this will provide a sufficient base for new layers to bond to. Finish by clear coating the entire panel will ensure a nice flat finish with no edges around the stripes. A base coat/clear coat paint system would be ideal if you intend to choose adding stripes consisting of more than one color. That way you can apply two coats of clear over the first color. If you get any overspray from the second color on the first, you can sand it out of the clear without damaging the underlying color coat. After applying the second color (and third, if applicable), apply two or three additional coats of clear over the area. Flash and drying times are also critical to a successful multi-color paint job. Applying masking tape or masking paper to freshly painted surfaces that have not yet dried adequately will cause you much more work. Product information sheets will provide a specified time to allow the paint to dry before taping. Likewise, clear coats must be added within a specified time or the base coat will need to be scuffed again using 800-grit wet and dry paper and additional base coats added. 16. Full Vehicle Re-SprayingQuestion: I would like to take this opportunity to know your personal preference on how to go about re-spraying a whole car. To be more specific:
Answer: The professional method of repainting a whole car is to remove the doors, hood, and trunk lid from the vehicle. Once you reach the paint application stage, the color would be applied to all areas. The doors are then re-hung back onto the vehicle and so is the hood and the trunk lid. Once everything is back on the vehicle, you would then re-paint them again in-situ. Effectively, you are painting the parts twice. This makes absolutely sure that all areas are covered, but more importantly you don't need to mask anywhere afterwards. So to confirm: paint the whole of the door (front and back), same with the hood and trunk lid, hang them back on, open all these parts, re-paint them, apply lacquer. Then shut them, paint the outside of the car, apply lacquer. 17. Graphics - ApplicationQuestion: I am painting my truck. The base color is speedway blue and I would like to put sun yellow graphics down the side. How do I go about putting graphics on without messing up the base color? Answer: This can be quite a difficult process to get it right. Unless you are a skilled graphic designer, painting graphics will be tough to achieve. The easiest, cheapest and most effective way is to have somebody cut them out of vinyl and apply them to your vehicle, i.e. stick them on. If you are feeling artistic enough, you could always try using stencils to achieve what you want, but unless you are able to get the edges of the graphics absolutely crystal sharp, it could turn out to be a bad idea. Stencils are often used when painting flames onto a car. However, the actual application stage is carried out using an airbrush. The purpose of this is so that the paint application is very thin and you don't end up with a thick layer of paint all around the edges. You could try visiting your nearest reputable graphic designer and ask them to design and make you whatever you require. 18. Auto Scratch RepairQuestion: What grade of sandpaper grit can I use on a deep scratch? Answer: Use 240-grit sandpaper first, going down to 320-grit in order to fine off the surface before applying primer. Question: My wife and I just bought a Honda Odyssey and it has a scratch in the door. We do not want to paint the entire door for one scratch. After getting the touch-up paint from the local dealership what is the best prep and paint method on getting the scratch to blend in to the original paint job? Would you use a little airbrush gun to do the job and if so what are some good ones to use? Answer: Touch up paint bought from a local dealership isn't the perfect solution to get rid of a scratch, this is dependent of course on the severity of the scratch. The method that we would recommend would be to flat down the scratch, i.e. sand the scratch out of the panel, apply up to 3 coats of color over the freshly primed area and then finish by adding a new coat of clear. By carrying out a local repair on the scratch using touch up paint, you will find it extremely difficult to blend in the repair properly with the surrounding paint finish. Afterwards, it would be highly visible where the scratch had been. Always bare in mind that touch up painting is only to be used for touching up minor chips, scratches and nicks and is not meant to be used on noticeable surface damage i.e. obvious scratches seen at a distance for example. 19. Paint Job AccessoriesQuestion: Could you recommend any ideal heat lamps or sanders etc. and where to buy them? Answer: Generally, 2-pack paint products should use medium wave or short wave infra-red portable stand-up heating lamps, that can be simply plugged into a mains electricity supply. Most who work in the automotive repair industry use medium wave infra-red. Any decent quality automotive equipment supply store or auto paint supply store would stock such items. For sanders, again all you would have to do is inquire down at your local auto paint supply store or automotive distribution center. Chicago Pneumatic would be an ideal choice of manufacturer to use for any home auto painter, they offer dual action air sanders for example for approximately $45+. 20. Repairing/Painting Plastic PartsQuestion: I’m trying to paint plastic parts in my truck such as the dashboard. After I painted it, some areas started to crack or as some call it ‘spider web’ out. How do I prevent this? Answer: First the dashboard needs to be cleaned thoroughly. Use a water based solution containing a mild detergent (i.e. dish washing liquid or similar). Next, clean again using a solvent based cleaner (i.e. pre-clean panel wipe). Next, using a fine scotch pad or high grade sandpaper, lightly rub down the whole dashboard (only gently to avoid deep scratches). Then apply 2 coats of single pack adhesion promoter (plastic primer clear). When dry, after 10 mins at 20 degrees C, apply 2 to 3 coats of vinyl coat paint (this can be bought from most paint supply shops). Allow 5 to 10 minutes between coats and allow to cure for 24 hours before handling. Question: I damaged the Flares around the right front fender on my 2006 Toyota Tundra. I bought new flares from Toyota, they came unpainted. How do I prep them for painting? Answer: First, clean the flares with a solvent based cleaner (i.e. pre-clean panel wipe). Then flat with 800-grit wet and dry before applying 2 coats of primer. When dry, flat the primer with 800-grit then apply 2 to 3 coats of color. Question: I have ordered replacement bumpers/plastic rear corner covers (e.g. Chevy S-10 Blazer, right/left corners) in the past and when they’re shipped they arrive damaged sometimes with a deep scratches that needs fixing. What is the best way to fix this damage? Answer: For the time being, we can tell you that repairing plastic is no different from repairing metal. The only thing that you do need to be careful of with plastic in particular is that you use flexible fillers. When you visit your local auto paint supply store to buy your products, explain to them what you wish to achieve and what type of material you are working with i.e. not repairing rigid metal panels but flexible bumpers, etc. and they will give you the recommended product in which to use. Question: I back-taped around the areas I painted but some of the spray primer (not much) got under the tape, how do I prevent this? Answer: Apply 2 lines of masking tape to prevent this. Question: I didn't blend my paint well and two of the areas I painted are lighter than the color of my car, should I repaint these spots? Answer: Increase the paint flow slightly to ensure the paint is going on wet and not dry. Question: When I try blending in silver paint i.e.
onto a bumper wing or bonnet, I can't figure out how to stop
that dull grey line showing around the area just sprayed? I
just end-up re-spraying the whole wing/bonnet! Answer: When painting silver it's important to
remember that due to the high metallic content of the paint,
the silver won't lie down on the panel that's being
painted. Question: After sanding my primer with 1500-grit paper it was smooth, I then applied 3 coats of paint which once dried had a rough feel. I applied my lacquer over this and was left with a rough not smooth appearance. Should I have sanded my paint or used a rubbing compound or should this be done to the lacquer only? Answer: Once the vehicle was flatted (sanded) with 1,500-grit paper and the base coat color was applied, if it dries with a rough feel, that is a fair indication that the paint (base color) mixture was either too thick or the paint was too cold, i.e.. the environment in which you were painting in was below 22 degrees C. If the paint is too cold and applied onto cold surface panels, due to cold environment temperatures, it comes out lumpy (to emphasize the point.) It doesn't flow properly. So make sure that you: a) Are
painting in an environment where the ambient temperature is at
least 22 degrees C. You shouldn't have to flat (sand) down base coat (color coat) in-between applications. We suggest that it was an environmental issue you were having; it was perhaps too cold on the day you were painting and the paint wasn't mixed correctly. It won't be a product related issue. Question 1: Clear coat is coming off of the aluminum rims? What can I do about this? Answer: Lacquer doesn't adhere to bare metal very well. The manufacturer would use a clear powder coating and not 2k lacquer. Strip all the old clear coat off of the rims (usingStarchem Paint Stripperor Nitromors paint stripper). Then flat the rims using 800-grit wet and dry flatting/sand paper (using luke warm water with a touch of mild detergent – NOT WASH AND WAX detergent), then polish the rims using metal polish (Autosol).
Question 2: Is it possible to get the rims coated with powder again? Or is the metal polish going to protect the rims just as well? The powder lasted about 12 years - I'm not sure how long metal polish will last? Maybe I'd have to polish the rims once a year or so?
Answer: I would polish them a couple of times a year, they look much better than powder coating. 24. Sanding Question 1: Can I wet sand the base paint before I put clear on it for a smoother finish? Answer: There should be no need to wet flat base coat before applying the clear coat. If there is an issue with the base coat, wet flat with 1200-grit wet and dry flatting paper, then re-apply a further 2 coats of base. Try to ensure a smooth and even application before applying |
