The Steps To Body Work and Paint Prep

Well, I figured I would post this for the benefit of all who wish to do their own body work but don't know where to begin. I will start by saying this is not a weekend task, and is far more involved than major mechanical work due to the sheer amount of time it takes to get it right. Expect it to take 2-6 months of spare time to do it properly. Doing it wrong takes less time, but may give acceptable results if the car is very straight or if you are not picky. Follow all safety procedures stated on the products and tools you use. You can buy another car, but can't buy back your health or eyesight if you ruin them. That being said, here goes.

1. Assessment
You will need to determine what the car needs before you begin. If the car has rust holes, you will need to note them and how much disassembly you will need to do in order to fix them properly. If the car is lacquer checked, there is paint stripping in order. If you need to replace any panels, or buy new parts, do your hunt and acquisition before you touch the car. This minimizes down time. You also want to be sure to have enough money to see the job through to completion. Many cars end up ruined because the owner did not have enough time or cash to get the job done in a timely manner. Body work that goes unpainted has a fairly short expiration date, so be prepared to either garage the car and not drive it, or spend every spare moment finishing it. I have even started buying paint before I start so that I know I have the materials to see it through. Just know that a decent paint job with materials, paint, sand paper, etc. will easily run you $1200-2000.

2. Fabrication And Rust Repair
The first thing you should do is cut out and repair any rust the car may have. Do this before you strip any panels so as to minimize the formation of surface rust. Do one spot at a time, and do any roof repairs last. This way, if the glass needs to come out, it will be prolonged and keep the car mobile as long as possible. If the roof needs to be stripped, do this first so that the windows will keep the material out of the interior. Seal any repairs using etching primer, which is available in spray cans. Avoid lacquer primers as they will not stop moisture from attacking the metal.

3. Paint Stripping
You will want to do any stripping next. Stripping is not always required on every car, and only needs to be done in cases of lacquer checking, peeling paint, or excessive buildup of prior paint jobs ( say more than 2). Stripping can be done mechanically with a grinder ( chews stuff up if you're not careful),Mechanically with sanding, mechanically with abrasive media blasting ( sand, baking soda, etc), or chemically with caustic stripper. Once again, after you are done you will want to use the etching primer to cover the bare metal in order to protect it. Stripping also requires disassembly to prevent damage to glass, trim, and plastic or rubber parts that are in the area to be stripped. Most methods will also require you to rough sand the now wavy remains of old paint smooth with some 60 or 80 grit paper before applying the etch primer.

4. Body Filler
Now is the time to get out the Bondo, All metal, or Dura-Glass ( depending on application). You will need to go to bare metal with any of these, but if you use Polyester Glazing Putty on minor flaws, you can put it over 80 grit sanded old paint instead. This can save time on dings and minor scrapes, but at $20 a quart, it is 4x as expensive as regular Bondo. Rough it into shape using 36-80 grit paper, then refine it with 220 grit wet or dry used with a guide coat and a hand sanding block. I like to use a jitterbug sander or Air File to rough shape my filler as they offer the best control, and can make straight lines. For the blocking, I have an 18in long Dura-Block, a medium soft block, and a paint mixing stick wrapped in sand paper. Cover the regular Bondo areas and any bare metal spots with the etching primer to avoid rust. Regular Bondo is like a sponge, and will hold moisture against the metal unless it is sealed. Remember too that you do not want to put filler on top of unsanded paint, or any kind of rust. This is also the time to remove any trim you want removed.

5. First Primer-Surfacer Application
Sand the whole car by hand with 220 grit paper, using a guide coat and blocking techniques to cut down minor flaws if desired. Then, apply 3-4 coats of Primer-Surfacer to give sufficient build. Next, dust the whole car in a contrasting color of paint from a spray can. This should only be a light dusting of paint, and you should still see the color of the primer over most of the car. Let it stand for a few days to reduce the sand scratch bleed through after blocking. Now, you are ready for the first blocking. Take care to protect the bare metal spots left over with the etch primer when done. It may take several days to block the car using the 220 grit paper on a variety of blocks. Always use the longest block you physically can to even out the longest flat surface possible. As much as is possible, move the block at 45 degree angles, making a crosshatch pattern on the car. This gives the best amount of contact area, and blends a wider area than straight up and down or side to side. Try not to sand in one area for too long, and move the block down the panel with a 50% overlap of prior sanded areas when blending. This way, you minimize waves in the finish. If you have a low spot that remains, you can use the Polyester Glazing Putty to fill it on top of sanded primer. Just be sure you clean the sanding dust off first, or the filler may not stick.

6. Second Primer-Surfacer Application and Blocking
Now that the whole car is blocked the first time, you are ready to do it all over again! This time, let the car stand for at least a week before final blocking. This allows the solvents to evaporate so that most of the shrinkage will take place an minimize sand scratch bleed through. Blocking in this instance will be done in 400 grit paper as that is the grit you want for best paint adhesion. Once you have blocked it, wash the car off and hit the whole car with red Scotchbrite pads to give tooth to anything you could not hit with the paper, and to even out the surface. This is the best way to do door and trunk jambs too as the irregular surfaces are hard to hit with paper. It is important to leave no glossy surfaces in the jambs if you are going to paint them. Anywhere you do not sand will likely peel within a year once the paint fully hardens.

7. Masking and Final Pre-Spray Prep
You are now ready for the paint booth. Before you get there, take the car to the coin operated car wash and give it a very good once over. You want to blow out all of the little nooks and crannies, and be sure to clean off any sanding dust residue. If it blows off some of your primer, or old paint, count yourself as lucky. It could have been the new paint that blew off.

I like to buy 3 or 4 plastic sheet drop cloths at Wal Mart for masking. I run 2 in tape around the flanges of the jambs and the trunk lip, then stick the plastic to it and cut off the excess. DO NOT BUY CHEAP TAPE!!! I also run a single sheet of plastic from the top of the windshield to the radiator, and tuck it down in there to keep paint off the radiator support and engine. I cut the sheets with razor blades that I buy in bulk for body work. As for windows, I run a piece of 2 in tape around the edges, then I tape the plastic to the tape on the window with another piece of tape. This makes a good line, and is easier to do than trying to do it all with one pass of tape. I also bring a jack and stands with me, then jack the front up on the stands and put the axle center on the jack pad. This way, I can remove the tires and wheels and don't have to cover them. It has been my experience that the tires will always get a little overspray behind the covers and wind up looking dusty. Just be sure you do not set the car too low as the gun will blow dust off the ground and onto the fresh paint.

Once you have masked the car, and set up any parts to be sanded separately, Take out your blow gun and blow out all the nooks and crannies to eliminate dirt that may contaminate the final result. Next, you will need to wipe it down with a wax and silicone remover to eliminate any oils that may be on the car from your skin. These can cause fisheyes and ruin the finish. Finally, use a tack rag to wipe off the surface and remove any dust that may remain. This is the last chance you will have to minimize finish flaws before spraying.

I am not finished with it yet, as I have another post with tips on how to do these things planned, as well as some short cuts, and a whole other section on how to paint a car as well. For example: Razor blades can be used as mini Bondo spreaders, as well as rough in tools on small sections. Also, how to plan your painting pattern. Because you need to know the order in which to paint the different parts of the car. Then there will be another section on the trials and tribulations of wet sanding and buffing the final paint, followed by vehicle assembly techniques. I do have plenty of pictures to document it as long as Myspace lets me host them there for free ( Most are already online on my Myspace page). I will however stress that while I pretty much know what I am doing, I am not, nor have I ever been, a professional body man. I have never been trained to do this, but picked it up from reading, trail and error, and valuable advice from professionals I have encountered along the way. I'm just a pizza delivery driver. So please, no one sue me if you mess up! Better yet, if you are a pro, post some feedback.

I will be painting in about 2 weeks provided I can find a helper to follow me in my truck to the booth, and help me set up. I will bring the digital camera and laptop with me, along with a change of clothes, so I can sit in Starbucks while the clear dries and post up some pics. The car will be painted in 2 stages, with the disassembled parts done first, and the shell, doors and trunk lid done assembled. This is how GM did it in 1985, so this is how I will do it in 2008. Not all G bodies were done like this, but Cutlass 2 doors were. I expect the whole process to take a marathon 24 hours from start to finish including drying time and reassembly to get it home.

I am renting a place in North Clearwater Florida. I have not confirmed that it is still available as I have not used it in 3 years, but I have been going there for the past 15 years or so.

Well, to do my color in base/clear in a cheap system, it is $500. In a top end system, it is $730. For my money, it is not worth going with cheap paint, especially in Florida. I went with Omni last time, and it was dead in 3 years. At $500, I was not happy! This time, I went with BASF's Diamont system. I previously had used PPG's Deltron, but PPG's Omni pissed me off enough to make me try something else. Omni is a hard paint to spray because it is very watery and has poor hiding. It runs too easily compared with Deltron ( if they haven't messed with it to comply with EPA regs), and takes too much paint to get good coverage. I put down a gallon of Omni base on a Mustang, and still did not get good hiding! Plus, I put down several coats of Omni on my Olds last time, and could see primer in several spots. So, avoid it. If you wanted good hiding with it, you would need more paint, and spend the same as a better paint. If you want a cheap paint, go with Nason single-stage in a slightly off white color. Bright white looks cheap on an 80's car, and may not have good hiding. White also hides less than perfect body work-which is important on your first job. Nason, however, does not come in an exact match for most factory colors, so it is best to use it for a full job. It was originally formulated for volume shops that do cheap jobs, and that is why you can't get a perfect color match.

Some blocking tools


In this pic are: 18in Dura Block used for long, straight sections; Paint stirring stick wrapped in paper, soft sanding block, Red Scotchbrite pad, and a small piece of CPVC pipe wrapped in adhesive 220 grit paper. Also pictured is the can of Etching Primer from Wal Mart. It comes out in a gray-green color and is transparent when applied properly. it needs to be sanded with 220-400grit paper before top coating with primer-surfacer.

Sanding and grinding tools



The Red sander is an Air File with a 12 in foot, the yellow one is a Jitterbug, there are 2 die grinders ( straight and 90), a small blue blow gun, a blue 3 in cutoff tool, and a 4.5 in angle grinder. The Red sander is the cheapest Air File I can find, and while it is slower than pro models, it is the only one I have found that my small compressor can keep up with.
Most of these items can be found inexpensively at your local Harbor Freight Tools store. I paid $0.99 for the blow gun, $15-20 for each of the die grinders ( they can be had for under $10 on sale), and the Air File is as cheap as $35 on sale. The Jitterbug is around $20, and the cutoff is about the same. I have seen angle grinders for under $20 and consider it an essential tool when working on cars. Some items are borrowed, and some I own. I do not have the welder pictured because I borrowed it from a neighbor and gave it back.

Chemicals and Paint Guns



The big gun is a 1 quart Devilbliss siphon feed that I use for top coats, and the small one is a $10 touch up gun I use for jambs and small primer jobs.
The big red can is the primer/surfacer, but with a $1.57 pour top lid from Wal Mart to make it easier to pour without spills, the small blue can is $0.97 Wal Mart black paint for a guide coat, the big blue can is paint stripper, then there is enamel reducer to cut the primer with ( it does not say to do it on the can, but it will not spray otherwise!), and the lacquer thinner is to clean the guns. The fillers are normal cheap Bondo, US Chemical All Metal for seam filling, and Evercoat Polyester Glazing putty for final touch ups.

Compressor



This is my undersized compressor. It works, but it runs out of air mid way through a job, and then you need to give it a few minutes to catch up. This only becomes an issue when you are using it to do a large area of filler. It is a 25 gallon Craftsman from about 15 years ago with a single stage compressor, and runs on 110 house current. Many larger ones run on 220. Two stage compressors are better, but are rare in smaller models. In this pic, it is outside my laundry room since this is the only outlet in the house with a big enough circuit to power it without tripping the breaker. However, I did burn out an outlet and a circuit breaker earlier this year.

Here is my car near the beginning of my paint and body project. In this pic it has been wet sanded in 220 grit paper, and still has some of the white guide coat on it from this first step.



Here is the car after the first priming and blocking with 220 grit paper. Note that the primer has been sanded through in this stage, and that some polyester glazing putty has been added to fix a few low spots. Also, the front fender has spots of Etching Primer on it where I sanded through.



Here is a fender after the first few pases with 220 grit paper. Note the black dots. Those are low spots left by a grinder I used while stripping the panel, and need to be filled. The fender came out pretty good, and all of these marks were eliminated in the first coat. It still needed a little work on a few low spots with the polyester filler to get it perfect though, as the primer can't fill really deep flaws.



This is the car with gray primer/surfacer on it. The black stripes are the guide coat. It will be sanded with the paint stirring stick and soft block wrapped in 400 grit paper as it is the final blocking before paint.

Bumper Covers

(Incomplete)
This is easily one of the worst parts of prep work. If you have the money and can get new covers, do so if your old ones are crappy. You see, the problem is that the plastic beneath the paint cracks over time, and this will transfer to the new paint above. Now, if you can't get new ones, you will have to make do as best you can with the old ones. If you need a used one, search for one with original paint as it will require much less work than one that has a few paint jobs on it. That being said, I will give a few tips for how to deal with problems and prep.

Peeling Paint
If your cover has peeling paint on it, you will need to remove the peeling section and then feather it in to the rest of the paint. If it is really bad, you may have to strip the paint with a special bumper cover paint stripper. Normal stripper will turn the cover to goo, so don't use it!

Fake Chrome Trim

If you can get new stuff, do so. Otherwise, you will need to do your best to salvage the old stuff. If you can't get a new set, and the old ones are glued in place, don't remove them! Instead, sand them well and paint them silver. Be sure to make them as smooth as possible, and remove any plastic that is peeling. This is not a perfect way to do it, but it can be made to look reasonably good.

Cuts and Breaks

If it is cut badly, get another cover. It is not easy to repair this with the repair epoxy and have it look good or last long. If it is just a small cut, you can use the rubber bumper repair epoxy in the crack, and use it on the back side with some fiberglass tape used for drywall to add strength.

Sanding

I like to sand the whole cover in 400 grit right from the start. There are too many little nooks and crannies to be certain that you will get everything the next time you sand it. Be sure to completely de-gloss everything before you proceed as any place you miss will peel in time. To get in to tight areas, you can take a Bondo spreader and wrap in in sand paper to use it as a block. I use this method by the silver trim pieces between them and the bumper cover.

Filling Minor Flaws

I use my Polyester glazing putty for minor nicks and scratches instead of the flexible bumper putty because it sands better. In a small section less than 1/4 in wide, it should not be flexed enough to crack unless the bumper would be damaged anyhow. Again, this is a make-do solution and should be used only for very minor surface flaws and not for anything structural.

Priming

When priming, I use SEM Flexible Bumper Primer instead of the normal stuff. I will use it with a guide goat for the final sanding, but again, I will only use 400 grit paper. Unless you have a lot of work done to it, one blocking should be sufficient. Just remember that the goal is not perfection, but good blending. These parts will never be perfect, but if you can make a good transition between areas, no one will know that they have been fixed.