I've put these pages on the site to help others who might not have a lot of experience with body work and/or painting. What I offer here is what I've learned from others; books; and on my own. Remember there is usually more than one way to do something and still have it come out fine. I'm trying to show how a novice might over a course of time repair and paint his specialty car using common inexpensive equipment (relatively inexpensive) in a home garage/shop. The following is what has worked for me, but I'm always looking to improve, so I'm open to suggestions. Sum

- Initial Thoughts -

Where I live you can take a panel down to bare metal and if it is inside you won't get any surface rust on it over a period of time. If you live in an area where you will get surface rust then I would work on one panel at a time. Taking it to bare metal, doing the body work, and then priming it with the first coats of primer. I would do all subsequent coats of primer and block sanding when you have all the panels ready for the top coats (base color coats and clear coats in my case). This method of working on one area of the vehicle at a time is probably best no mater where you live as you then don't feel so overwhelmed. Now if you are doing drastic customizing similar to what I did you might want to do all your major cuts and tack everything together to make sure that you have the look you want. Then final finish one panel of the vehicle at a time. These are just suggestions.

Equipment Tip: If you are going to be painting a whole car you are going to need probably at least the following: 5 hp. single stage compressor (2 stage would be much better, but I got by with this as my HVLP gun doesn't need a lot of air and I painted things apart); Spray gun that doesn't need a lot of air or a large compressor and one that can produce a good job (see my suggestions later); sanding boards (long, medium, and a couple of rubber sanding blocks (hard & soft); M.I.G. welder if you are welding in patch panes and/or customizing; air die grinder, 4 inch electric grinder, air cut-off wheel (all of these to finish your welds up and to install patch panels). The following would be nice, but not absolutely needed: DA sander and a low speed or variable speed buffer/sander. I would stay away from a long board air file and other air sanders even the DA until you gain some experience as they can get you into more trouble than they are worth and you’re not a production shop. If you don't like sanding stop right now and find something else to do with your time, because you are going to be doing a lot of it if you want a good job.

Spray guns: I've had the HVLP gun that I had bought for doing primers for a couple of years. I found out that it will spray the base and clears to my satisfaction also. I would also check with Len at his Internet Auto Body Store for his recommendations. His Sharp Platinum would probably work fine also. These will both work with a small compressor. A top of the line gun like a Sata is great, but it puts out a lot of paint, like a body shop needs for production work and a fine finish but since it puts out so much paint that can get a novice into trouble if his gun technique is not great (read runs -- but runs can be fixed). Due to its air requirements (read large) it also needs a 2 stage compressor. I would love to have one though someday. Remember if you are going to color sand and buff at the end you can live with some orange peel in the finish paint. The gun I'm using produces very little if I use it right and even though I haven't color sanded yet I could to get a truly outstanding final finish.

Your Health: I finally bought a supplied air hood from Len at his Auto Body Store about 2 years ago. I wouldn't paint without it now. Not even the primers. The paints I'm going to talk about are all 2 part paints, except the base, and can be VERY DANGEROUS. Don't let this project kill you now or shorten your life get a supplied air system. I used a charcoal mask for a long time and am still alive, but these just don't get it even with new canisters all the time and I might pay down the road. These paints aren't like the ones that were used even 15 years ago. They are dangerous, period. One of these systems will cost you from about $350 to $450 depending on which you get. If you are broke do like I did and buy a cheap gun and put your money into saving your life. Remember you are not painting in a spray booth that moves tons of air every minute through the booth. At least spray the primer with your shop open and new charcoal canisters and as much air as possible moving through (not easy in the winter) and also not possible when spraying the sealer, base and especially the clear.

Wear a dust mask while sanding and grinding. Wear a face shield while grinding. Wear ear protection while grinding. Get an autodarking hood and you will be a better welder (I got a nice one from Harbor Freight for about $140 that has adjustable shades and more importantly a lens that is big enough for me to see out of with my bifocals).

I wear gloves all the time. The cheap white cotton ones will work great while sanding. They keep your skin oil off the surface and you can actually feel the surface better for highs and lows with them over a bare hand and they protect you from the sandpaper. I wear latex gloves (I buy them by the 100 from Harbor Freight) while using the bondo, the cleaners (oil and wax remover -- PPG 330), and while wet sanding. You will do a better job with the gloves on.

So now let's get going.

- Pre-Bodywork Prep -

All the work I've done on my truck and teardrop trailer has either involved taking the metal down to bare metal or using new metal. I stripped the frame, suspension, small pieces, and most of the body by sandblasting. If you use this method you have to be extremely careful of the body sheet metal so it is not warped. I made a pressure blaster, but for a home shop I would probably now buy Harbor Freight's pressure one that is often on sale for less than $100. I used what is called blow sand (blows around the country here) that is native to southeast Utah. It is extremely fine and not very aggressive so be very careful with commercial sandblasting sand. Now I use a stripping wheel to take body panels to bare metal and that would be my recommendation. Eastwood Company has these disks and they look kind of like scotch pads and you can use them in a drill, air drill or a grinder depending on type. They will leave the surface in about the same shape as worn 80 grit paper which is about right for primer. Others use 80 grit sanding discs and Len has these in a convenient hook and loop configuration on his Auto Body Store. If you strip a panel at a time and work on it you will get by this step as boring as it is.

All bare metal that is to be primed should have some tooth to it and the scotch pad type discs and/or the 80 grit will achieve this. If it is new metal like I used to build my bed and teardrop then you need to at least hit it with 180 grit to give the primer something to get hold of . Now any areas that need bondo I would hit with 36 or 40 grit discs as this will give you a good surface for the bondo to grip. Don't get carried away with these discs as they can remove metal and make the panel thinner.

..............................................................................- Bodywork -

First let me talk about primers and bondo for a minute. I've used PPG primers on my projects and Dupont top coats with no compatibility problems (see following for which ones). I like the PPG products better for a home repair environment, but they are 135 miles from me and Dupont products are 70 miles from me, so they are quicker to get to if I need extra during painting the critical top coats. There are a lot of good brands of paint on the market, but these are what I've used. I will probably use PPG all the way through in the future as I believe some of their products are a little better for a rod and a home painter than some of the other brands. None of this paint is cheap, but you're not buying it every day like a production shop and you probably want your project to get the best.

Next, with some of the new primers (not the high build) you can put the bondo on top of them. For my type of work I don't do this. The main reason is that the PPG DPL40 primer that I like for the foundation coat has to be top coated within one week with either bondo, a high build primer, such as K36, and/or the base and clear. Now if you’re working on your vehicle as a hobby you probably can't meet this time frame. If you don't, you have to scuff or sand the DPL40 and then apply more DPL40 and top coat this within a week. For this reason I like to do it the old fashion way of taking the metal to bare metal; applying the bondo; then start with the primer coats when I can put the DPL40 on and then topcoat it with K36.

Okay, at this point we have a panel that needs to be repaired and it is down to bare metal and the area that needs bondo is roughed up with a 40 grit disc. Also the area is relatively flat after hammer and dolly work if that is needed. I don't like the bondo to be much more than 1/16 inch, but to be honest I have quite a few areas that are 1/8 inch and maybe a couple that are thicker than that. The more bodywork you do the better you'll do so don't be too hard on yourself. I have over 70,000 miles on my truck as of this writing and none of the bondo has fallen off yet. I think some people make too much of finishing with no bondo and that keeps a lot of people feeling they can't do their own projects.

Bondo Mixing Tip: I like to mix my bondo on a piece of flat glass. I use an old side window from my truck. It will not absorb any of the bondo (don't use cardboard) and is easy to clean. I put a ball of bondo on the glass and a proper length of the hardener next to it. I use two of the yellow spreaders about 4 inches long to mix it. Use one and then use the other to wipe it off the first back onto the glass until mixed. After putting the bondo on the car I scrape any left over off of the spreaders and the glass with a 1" wood chisel. Then I take some paint thinner on a paper towel and finish cleaning the glass, spreaders, and chisel. Believe me if you keep all of this clean you will do a better job. If not you will get chunks of old bondo in the new on the car and if your spreaders aren't clean and straight edged you will drag grooves in the new bondo as you spread. (Note: These types of tips are going to make this longer, but I don't see this stuff mentioned in the books and it can really help speed the process up and make it less frustrating, so bear with me or skip over my tips).

I spread the first layer (if it is a large area that is going to need a lot of work) of bondo on relatively thin and IN ONE DIRECTION PRESSING THE BONDO into the scratches on the metal. As soon as this sets I hit it with a long board that has 40 grit paper on it. Get the bondo at least a couple of inches past the repaired area. Don't be afraid to get a large area covered with the bondo. You will be sanding most of it off. If I was doing say a fender from a 30's car that was okay, but still not perfect I would cover the whole fender with a skim coat and proceed.

Cheese Grater Tip: I don't have much luck with the cheese graters to shape bondo that hasn't quite kicked. Work on shaping the bondo with the spreaders and you won't have much trouble just using your sanding boards to shape the bondo.

Sanding Board Tip: I have two long boards (mine are a yellow plastic and have a bottom that you attach a long piece of sand paper to (already cut for this)). I keep one with 40 grit on it and the other with 80 grit on it at this stage. I also have two medium length boards of about 8 inches long (one for 40 and one for 80 -- they take sand paper that I rip to size from a full sheet and clips on the end that hold the paper. I also use a couple of rubber sanding blocks that are about 5/8 inch thick and about 2 X 4 inches. One is hard and the other is black on one side (medium hard) and white on the other side (soft). I also have misc. pieces of rubber hoses of different diameters that I can wrap sand paper around. Don't use your fingers (except in the smallest of areas) as if you do your surface won't be flat and that is what we want.

So with the first layer of bondo on you want to rough cut it into shape with the longest board (covered with 40) that you can use for the area you're repairing. Do all of your sanding in X type movements and change the direction of the X pattern constantly. You are really shaping and cutting with the 40 grit, don't worry about the sand scratches and let the paper do the work. Don't bear down. Work form the good parts of the metal into the repaired area. This will help you achieve the final shape. On a shape like a rounded fender side never sand along the fender line. Start by putting your board horizontal to the ground and grab both ends. Now sand in an X pattern from say the bottom right up to the top left going over the curve of the fender. After a couple strokes this way switch so you start at the bottom left and sand to the top right going over the curve of the fender. Don't stay in one place. As you are going up and down over the curve in the X pattern constantly move the X pattern to the front or back. You can take a long flat sanding board with paper on it and in this procedure work a shape with a curve like a basketball at this stage. Treat all curved surfaces in the same manner regardless of rather you're using the long board or a smaller block to sand. Remember we are shaping at this stage and not sanding. During the final sanding work in the same manner.

You will soon sand through in areas to the bare metal. Now you have a decision to make. Is the bare metal high (a bump) and need to be knocked down or is the surrounding area with bondo on it low (a dent/depression) that needs more bondo. If it is high take your body hammer and dolly and knock it down some (you probably need the dolly behind the bondo area and hit the high area until it is a little low or flat. The dolly will raise the low area as you hit the high area. Be careful of hitting the metal with the dolly directly behind it as this can stretch the metal and cause you problems.). In all of the areas that are sanded out and where the bondo stops the bondo should not have a definite line at the edge, but this should be a very tapered area with the area going from bondo to metal with no apparent edge.

Change your paper when it wears out. Don't force it or you will wallow the area out and have to keep applying more bondo. Don't sand the low spots. Sand the high spots down to the level of the low spots and if you hit metal or start going low stop and add bondo to that area and past it a little.

Now you are going to need for sure to put a second and maybe a third and fourth coat of bondo on the repair if it is a large area and you are doing this for the first time. You will get to where you finally have all the lows in the area filled and the area will have the proper shape. Stop just a little on the high side while doing this (about the thickness of your sand scratches).

Now I would put a very, very thin coat of bondo on the whole area. Just spread the bondo so you are taking it almost all back off with the same stroke. It is just to fill the sanding scratches and any pinholes you might have and you are not trying to build any thickness at this point (use premium bondo and mix it right and you shouldn't have pin holes). Now what I do next and a pro wouldn't do this, but it will help you and me immensely is to spray a guide coat on the area.

Guide Coat Tip: A guide coat is taking a contrasting paint that is a different color than the work area and misting that paint on the area. Spend a couple of bucks and buy a spray can of the type that is made for this. It will go on nice and you will be using it later with the primers. 2 cans should be enough for the whole project. Just mist it on. You'll see that you don't need much.

With this light guide coat on the area switch to your sanding boards with the 80 grit on them. Let the paper and the board do the work and sands the area flat. The guide coat should disappear along with the 40 sanding scratches. If it is still visible you have a low spot or a pin hole or scratch. Take a little 80 with your finger or block and sand the guide coat out of the low spot and apply more bondo and then more guide coat and then sand again. If you do all of this the area should now be ready for primer. Some people will now go over the area with 150 or 180 and some will use even 320. It won't hurt, but I don't do it as in the priming steps I'll end up putting a lot of primer on and sanding it off and it is designed to fill 80 grit sanding scratches. If I was latter just repairing a panel on the car and trying to keep the primer to a minimum then I would go to a 150 or 180 at this stage. You be the judge.

Hint: You can use the guide coat earlier in the bondo shaping steps. With it you can instantly see if an area is high or low. The more normal procedure is to run your hand (flat) over the area to feel them, but this can be tricky to get the hang of at first. Use the guide coat and don't tell anyone ;-).

- Priming -

Paint can be a real personal thing, so bearing that in mind I'll tell you what I use and why and also how I put it on, but these step can be done different ways with different products and still achieve good results.

- PPG DPLF40 Primer -

I coat all of my bare metal and bondo areas with PPG's DPLF40.

Note: The number at the end denotes the color as this comes in a number of different colors. If you are going to be using a light final color you could use a light color here. Not so important at this stage, but the DP can also be mixed as a sealer and you want your sealer to be close to your final color so you don't have to use as much base color to hide the sealer. Also I used DP on my truck and it is now been replace with the DPLF (LF standing for Lead Free). Only time will tell if it is as good as the DP that came before it.

I am not sure of the other paint suppliers having a product quite like the DP and would like to know if they do. It is very corrosion resistant and bonds very well to bare sanded metal and bondo. It is an excellent foundation between the metal and high build primers. It is a non sanding primer though that is not meant to fill and has to be top coated within one week with another primer or other compatible top coats. The reason for this is that paint bonds to a surface through either a mechanical bond (the need for the fine sand scratches) or a chemical bond (epoxy) and this paint does both, but since you don't sand it the paints on top of it have to be applied within a week for the chemical bond to take place since there isn't a mechanical bond between them and the DP. This is the reason I don't put it on and then bondo over it, since working as a hobbyist I might not get the bondo done and the whole works top coated within a week. So I do the bondo work and then shoot the DP followed by the K36 in the appropriate time.

This combination has worked great for me and with over 110,000 miles on my GMC it has not failed in any way and I've been on the salt flats with it for over 35 days and this is an excellent test plus I've put on many miles in the rain and snow. If I lived in the rust belt and had a car I wanted to keep I would for sure use it.

A note here about etch primers. Personally I don't use etch primers. I feel the DP is superior for my projects as it provides an excellent bond and also protects the body from corrosion (read rust). I've noticed that a lot of times the rock chips I get in the paint go down to the K36 primer or the DP primer, but hardly ever to the bare metal. So if I get a chip down to the DP level it still isn't going to rust. Etch primers are cheaper and have their place. That place I believe is in production work. Now you don't want to use both, so decide if it is going to be DP or etch, but I would use one or the other for the first coats on the bare metal unless you are using a system that has something else.

I first blow off the bare metal and the repaired (bondo) areas to be painted with my air nozzle. Next I clean it with PPG's wax and grease remover #330.

Next I spray the panel with 2 coats of the DP (mixed as per instructions). You can use 1, but I prefer the 2 to make sure of my coverage and paint thickness. One other thing is the DP can be kept for a while after it is mixed. I've kept it a few days in the frig and it was still good. Read the instructions and don't forget after it is mixed you have to wait 15 to 30 min. (depending on the activator you use) before you can spray it.

Paint Mixing Tip: Here is something I learned from a painter friend a couple of years ago and now use all the time. You can mix paint in all kinds of ways, but I've found that the most accurate, simplest and easiest for me is the following. I bought the glass Pyrex mixing bowels (the clear glass with handles and graduation marks on the side) in 4 sizes going from their smallest on up.

You mix your paints in ratios, for example 4:1:1, which might be 4 parts primer to 1 part reducer to 1 part hardener (this is only an example). So if I wanted to spray a small part I would fill the small mixing bowel up to the 4 oz mark, and then pour the reducer in to the 5 oz mark and the hardener in to the 6 oz mark. This would give me the 4:1:1 ratio.

Say I'm going to paint something larger like a panel. I would get a larger bowel out and fill it to the 16 oz mark (4 parts) with primer. Then I would add fill to the 20 oz mark (1 part--4 oz) with reducer. Finally I would fill to the 24 oz mark (1 part--4 oz) with the hardener.

It is simple just keep the ratios the same.

It is then easy to pour from these containers through a strainer into your gun. I clean the gun parts in them and they are easy to wipe clean with a paper towel and paint thinner. Keep them and your gun cleaned spotless every time you use them and your gun will keep working for you the same way.

. - PPG K-36 Primer -

Note: the K-36 is a high build primer designed to fill low spots and sand scratches from body work. It will be sanded and then top coated. I used K-200 for the primer on my pickup, but even though it is a 2 part primer it IS NOT WATERPROOF. I didn't have any problems in the years I ran around in primer because the DP40 was under it and provided the moisture barrier. K-36 is a superior product to K-200 and it is waterproof, so it is a better product than the older K-200. It also sands super.

After spraying the DPLF40 I will wait the appropriate time (but not over a week) and then spray on 3 wet coats of K-36 mixed as the normal build. I'll usually do this the same day or the next.

Before spraying the K-36 over the DP I first blow the area to be painted off with my air. Next I clean it with PPG's wax and grease remover #330.

The purpose of the K-36 is to give you some paint thickness so you can sand it down to fix minor imperfections on the surface. Think of it as your tool to fill the low spots that are left at this stage. If you do your body work before this stage good you don't need to mix this in it's high build form (I always mix it in the normal regular build vs. the high build ratios). If you do mix it in the high build form, don't forget your spray gun might need a bigger tip to allow the material to pass through.

Also this stuff hardens fast so don't mix more than you can use in the next 60 minutes (see it's instructions) or it will harden in the gun. Clean the gun immediately after spraying and follow the directions for flash time between coats.

After the K-36 has dried, preferably overnight, you will block sand. Spray on a guide coat first (as mentioned earlier). Next I sand with 180 grit dry or 220 grit. USE YOUR COTTON GLOVES TO KEEP OIL FROM YOUR HANDS OFF THE PAINTED SURFACE. Different people use different grits in the steps I mention here, but there again this works for me.

Use your different sanding boards and blocks for this step. Use the longest board that will work in the area you are doing. This is the most important step to a great paint job, so do it right and don't rush it. I buy the 180 in a roll and then tear it to length for the block or board I'm using it on. In this form it has an adhesive back and works a lot better than sheets of sand paper, but you can do that also. Change you sand paper as soon as it stops cutting. Don't push it or you will start wallowing out spots. Knock your paper often to remove sanding dust from it and wear a mask.

Remember you are sanding, but really you are cutting off the high spots down and removing the 80 grit sand scratches. Sand in your X pattern and constantly move the area of the X around and do the X from different angles on flat areas. Do the curves like before, by sanding over the curve in an X pattern and not along it. You sand until the entire guide coat is gone. If you see an area where you start to sand into the DPL40, but next to it you can still see guide coat then the guide coat area is low.

Now it is decision time. If is so low that you can almost sand it flat then the next coats of primer might fix it. Don't sand into the DP. It is okay at this point if you barely sand into the DP, but don't sand to bare metal.

The exception to this is if you really screwed up earlier and you have a definite high spot that needs to be knocked down. If so take your hammer and dolly and gently knock it down. If you do this and/or you have a definite low spot this area is going to probably need more bondo. I say bondo, but the stuff you used on the bare metal is not the best for this stage. Get a type that is meant for this. Make sure it is 2 part and not the old stuff in the tube. Buy it the same time you get your main bondo. Dupont's name is Final Fil. These products are made to go over primer and they sand extremely well. If you use it at this step (it can also be used in your panel repair steps) be sure to sand it with 180.

Now spray on 3 more coats of K-36 over any of these repaired or low spots. Before spraying again blow the area to be painted off with air and clean it with PPG's wax and grease remover #330.

Next guide coat the area and sand it with the 180.

When everything has been sanded flat (no more guide coat showing) with the 180 then shoot on 3 more wet coats of the K-36. Before spraying again blow the area to be painted off with air and clean it with PPG's wax and grease remover #330.

I sand these coats of paint flat with 400 wet sandpaper (here again some will then go to 500 or 600, but the 400 has worked with the sealer, base and clear I've used). This paper I get in sheets.

Get a bucket of clean water and squirt some dishwashing detergent into it (just one squirt). Get a large sponge. Put about 3-4 sheets of the 400 sandpaper in the water. You want them wet and soft. Put on some latex gloves or you will sand your finger prints away ;-).

Get a good stir stick that is thick and straight. Wrap one of the sheets of the wet sandpaper around the stir stick over and over until it is all wrapped around the stir stick. This will be your sanding block for most areas. For sharp curves use a hard rubber sanding block and for real tight curves use a softer one.

Guide coat the panel next. Now put some water on the panel with the sponge and sand in the same manner as before (moving X patterns). Try to keep the sponge with water on it above the area you are sanding. Keep dipping the sand paper into the water to clean it and keep water on the sanded area to remove the sanding residue you are creating. You can use two hands on the stick, but stop often to rinse the area with water. This actually goes pretty quick. As soon as the paper is not cutting tear off the paper down the length of the stick and the width of the stick. Since the paper is wrapped around the stick you keep having new paper each time you tear it down the stick until it is all gone.

During this step we need to keep the flatness achieved in the preceding step when we sanded with the 180 grit (that is why it was so important to get the final flatness during that step). Our main objective is to sand the primer down until  we get rid of the 180 sand scratches and to provide a very flat smooth finish for the sealer, base and clear. Sand until the guide coat is gone. You will see there is also orange peel created when we spray on the primer. This has to be sanded flat and the guide coat will help you here.

It is also possible to still find low areas. If so this is your last chance to fix them. If they are there then do what you have to fix them now, but be sure once they are fixed they have been sanded down with the 400.

Note: Long flat areas like hoods, doors, and sides are going to really show if they are not flat. Wet the primer and get some lights on them so you can look down them and make sure they look good with no waves or ripples. Curves, such as fenders, are going to be more forgiving and small curved areas, such as jambs, and window moldings are going to be the most forgiving if they are not perfect. I spent too much time on some of the small curved areas and didn't need to, but it is better to error on too much attention to detail. After this stage what will happen is that when you put on the clear it will highlight the bad areas not cover them up. They won't go away. Not to scare you too much, but get it right before you go to the next step. The guide coats won't lie to you. If you sand things flat and don't go into an area and just sand the guide coat away (wallow out the area) you will be fine and you'll have a great paint job. Everyone asks who painted the car, but it is these steps that make a great paint job, not the painting of the base and clear.

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Last modified: 01/09/06