This is a long process boys and girls so get ready to dig in and do it the right way. We’re not talking about pulling major dents, fixing rust or any other type of major body work. This comes after all of that is already finished.
There is quite a bit to this process if you want to get it right. I’m sure that you have seen a car that you look down the side of them it looks perfect. You try as hard as you can to find a flaw, but it’s just not there. The car is smooth as glass, that is what I will show you how to do in this article.
This is what I call finish body work, it happens after all of the major body work is done. The car should be finished to the roughed in stage. By roughed in I mean all of the body work is finished to 40 grit sand paper. This is where the auto body finish work will begin.
At this point you need to walk around the car and feel the body work looking for high, or low spots in it. If you find some it’s no reason to worry; all you need to do is spread a little bit more filler on it and sand with the 40 grit paper again. Make sure to leave the body work just a little high.
After you have done this you can load the sanding block with 80 grit sand paper. Make sure that you block is about three inches longer then the biggest spot of body work on your car. Once you have the block loaded with 80 grit paper, your ready to begin the finish body work process.
What your looking to do here is remove the 40 grit sand scratches from your body work. You do this by stepping down the grit of the sand paper that you use as you move through the process. Now you should finish all of the rough stage body work to 80 grit sand paper.
Just like the rough stage body work, you should do walk around of the car and feel all of the body work for high, or low spots. If you find them this time, you’ll need to use metal glaze to fill them. Rather then plastic body filler; metal glaze is a whole different type of product, it’s designed for a different use.
Metal glaze is a thinner polyester body filler designed to remove small dents and scratches. It does a great job filling pin dents, or very small low spots in your body work, but don’t try to use it as a general body filler, it won’t fill large dents.
After you have fixed any areas that you need to with the metal glaze. We will move on to the next step of the process: which is quite simply changing to 180 grit sand paper on your sanding block. Now all you have to do is to sand all of the body work with 180 grit sand paper.
This is the final body work stage, you should do another walk around to make 100% sure that everything is flat and smooth. If not you will need to spread a bit more metal glaze om it. After it’s all smooth we’ll move to the next step of the process, cleaning and priming the body work.
I know that cleaning doesn’t sound fun, but it’s a very important part of the process. I always make sure that it’s all the way clean before I move to the next step of the process. Get out your tack cloth and go over the car; then use your air to blow out all of the cracks and crannies.
After you blow it off you can tack cloth it one more time. Then you need to get your metal prep cleaner, or wax and grease remover and go over the entire car thoroughly. After that your ready to prime your car; I prime the body work first on my projects.
I use either urethane or epoxy primer on my projects. When you use primer make sure that your always follow the manufactures mixing instructions. Or ask the auto body supply shop where you buy your supplies how to mix it if you don’t know how.
Make sure that you get mixing cups from the supply house. If you don’t know how to use the mixing cups all you need to do is ask them. Most supply shops will be glad to show you the mixing process. It is very important to get this exactly right; if you don’t it will cause big problems.
Once you have the mixing process down perfectly; you can mix the primer and spray it on the car. Make sure that your car is masked first. I usually spray three coats of primer on the body work areas first, waiting 15-20 minutes between coats for flash time.
The flashing process is a very important step, you should always give the primer time to flash between coats. If you don’t the primer will run, if the primer runs while your spraying it, this will only make the process take longer. Don’t get in a hurry with this step, take your time and make it right.
After you have your body work primed, you’ll need to give the car 24 hours to dry. You don’t want to sand the primer to quickly, this can cause other problems that you don’t want. After you have given the primer ample time to dry you can move to the next step of the process.
You’ll be sanding the primer in an “X” pattern with 180 grit sand paper on a sanding block or board. Once you have finished this step, you can clean the car again with a tack cloth, and the wax and grease remover.
Make sure that you check your masking, you don’t want any loose masking on the car. The primer is very hard to get off of any areas that you didn’t mask right. Make sure that you check your masking, or just re-mask the entire car before you do the final prime on the car.
Now that you have checked you masking, and made 100% sure that your car is clean, you can shoot the primers to it. You will need at least three coats of high build primer over the entire car, giving it 15-20 minutes of flash time between coats of primer.
Let the car dry for 24 hours, after you’ve let it dry you can shoot some guide coat to the primer. Guide coat is a special black paint that gathers in the low areas of your body work, so you can see your high spots, and your low spots in the body work.
After you have sprayed the guide coat on the car, you can load your sanding block or board with the 180 grit paper again. You will be sanding the entire car this time; if you want it right you should do this by hand. Machines aren’t as accurate as the old hand and eyeball technique.
Make sure that you always use a “X” pattern as you sand the primer. Your looking for perfection here. Because the next time you spray primer it will be the final prime before you paint the car, and this needs to be perfect, OK now your done with show car finish body work.