Now that you have the case taken apart to the level that you want it is time to prepare the surface for painting. Everyone has different ideas on how to prep the case for this job and some will say that their way is the right way or that you are taking a short cut but some of the processes depends on what you may have available to you. A majority of people out there do not have a professional paint setup with different spray guns, a paint booth and a way to bake the paint on. This is where the old spray can paint becomes a modders best friend. There are ways to have your paint job come out just as good a pro paint job, but you will have to work for it.
The first thing you want to do is make sure that you have done all the drilling, cutting, bending or what you want to be done to the case done before you start your painting. There is nothing worse than having all your painting completed and then find yourself having to drill more holes and chipping, cracking or scratching the paint up. Once you are sure that all the work you want to be done is done then let’s get to painting. One of the first things you will ask yourself is how much of the old paint do I need to removed and tell you the truth you will get a different answer everything you ask someone. Some think that you only need to rough up the surface while others say the only true way to do is is to go down to the bare metal. As I stated before this all depends on what you have available to you to achieve it. If you do not have a bunch of power tools at your disposal you can use the old tried and trued way of using your hand and some sandpaper. It will take a little longer but you got to do what you got to do, but if you want to help speed up this process you can invest in a small palm sander for $20-30 or more. Either way, you go you will need to have the most basic item, sandpaper.
Here is a bit of background on sandpaper, it is rough and scratches away stuff…lol, OK sorry but it is true. There are many different types of sanding paper and depending on what you want to do is what you need to use. The most basic thing that every sandpaper has in common is how rough it is which is known as the “Grit”. Just remember this, the lower the number the rougher the paper is; which in turn means the more you will remove, but at a price of more work later on. By using rougher grit sandpaper you can remove a lot of material in a short amount of time but this means that the surface is also much rougher with grooves that you just created. I am not worried about a little extra work so I like to start off with a 200 grit sandpaper as it takes off a good amount of paint and the scratches that it leaves behind are not to bad. When a good portion of the paint is removed then I like to step up to a finer grit of 400. This will continue to remove any paint that might be left behind plus it will start to smooth out any of the grooves that were made by the 200 grit paper. After all the paint has been removed a once over with some even finer grit paper, 600 grit, really smooths out the metal and this is what you want to help you get that smooth finish. Some will say that you do not need to go all the way down to the metal to paint the case and that is true, but a better primer is needed to help bond the paint. By jumping right to the 400 and 600 grit steps from above you can save some time and still get a good looking outcome.
Now that you have the items sanded and ready to be painted you need to do just a few steps to make sure that you get the best results for your hard work. This part is very important as it the foundation of your hard work so far and to come. A clean surface is a must for the perfect paint job and it can be had pretty darn easy by simply washing them. By using some clean water and a clean rag you can wash the parts down to remove all the dust and tiny partials that have gotten into every crack. Do not use any soap during the washing process as it will leave a film on the surface and it will not allow the primer to adhere to the metal. You must make sure that the items are fully dry before you do any sort of painting. If you are lucky enough and have an air compressor you can use that to blow dry the parts, but if not you can leave them out to air dry for a day or two (I do this even after blow drying them). The thing to do after the parts have completely dried is to wipe them down with a clean lint-free cloth. The best thing to use is something called a Tack Rag which is made from cheesecloth and is slightly sticky to the touch. The tackiness of the rag will pick up any particle left on the item making sure it clean. A tack rag/cloth can be bought a just about any hardware store for just a few dollars.
When possible I would suggest that you suspend the item you are painting. I am pretty sure you have seen it before where someone is painting some car parts on TV and you will see some of the items hanging. The reason behind this is for a few reasons with one being that you have easier access to all sides of the part. Another reason is that you will get a better spray out of the can fit you hold it upright. This will help reduce chances of overspray and the possibility of the paint “spitting” a bunch of paint out. And finally, it is just more comfortable to do it like this. If you are not able to hang the parts then I would next suggest some way to elevate the item to at least a workbench height for the same reasons listed before. Next, you should prep the area in which you are going to paint at. The area should be clean and free of anything that may go airborne and land on your parts. Laying down a drop cloth, which can be bought at any hardware store for a few dollars, before you begin any painting as it will help control overspray damage to anything that might be in the area and it also helps control loose objects from finding their way onto your project.
You now have the painting area all prepped and the pieces all nice and clean you are ready to start applying your primer and paints. If you are not able to suspend the items and have to paint them while they are flat you should consider elevating them on a wooden block or a small cardboard box. Why, well it allows you to move or rotate the item to ensure that all the areas get painted and that no places are missed. Plus if you paint it, say on top of some newspaper, you are running the risk of the paint sticking to the paper and thus damaging your paint job.