I have had a couple recent requests to post a detailed article on sanding and buffing your car.
I'm talking about basecoat/clear coat paint jobs here. You can wet sand and buff a solid color single stage paint but not a mettlaic or a pearl. Usually I just say when you do single stage you simply need to accept that what you get is what you get and just accept it and leave it alone. So if you are useing basecoat/clear coat here is how
1. Wash the car
2. Wipe the car with a mild solvent or commercially available wax and grease remover
3. Buy 3 or 4 sheets of each 2000, 1500,and 1200 grit wet and dry sand paper
4.Were going to walk down a ladder here and then back up again. I can’t see the condition of your paint so I can’t tell you which grit to use. Start with the 2000 grit if that seems to be leveling the surface great. If you determine that it’s just not doing the job go with the 1500 if that isn’t getting the job done go to the 1200. Now let’s say you have to use the 1200 after you have introduced throes scratches your going to have to cut the tops off of the scratch with the 1500 and then again with the 2000 grit. You can see you will be doing the whole job three times with this example so you want to get the job done with the finest scratch that will work.
5.Start with the finest grit, 2000 put a couple of sheets into a bucket of warm water and add a few drops of detergent (I just use what ever I'm using to wash dishes with at the time) and yes I almost always wash the dishes at my house. Let the sand paper soak for at least 15 minutes until it curls up we want the sand paper saturated. The detergent is for lubrication. Wrap the sand paper around a sanding block or a sponge and as you sand keep the surface wet and dunk the sand paper often a single piece of sand paper goes a long way if you keep it wet. When you are done the surface is going to look very dull and to bring back a shine we have to get rid of the sand scratches.
6. This is the point at which you need a piece of equipment; the standard of the industry is a 7” polisher you can rent these or purchase them form $75 -$400 Pads for the buffer are made off wool or foam. I like foam pads they don’t last as long as wool but I’m less likely to scorch the surface and I get better results. You will need two pads (a dense firm pad for compounding and a soft pad for polishing)
7. With old paint a rubbing compound was used to scourer the surface it had an abrasive in it but with modern urethane clear coats we need a rubbing compound that actually reflows the clear. Squirt some on to the surface and “butter it in.” That means spread the compound lightly with the polisher used at low speed and then let it sit on the surface thirty seconds or so to let the chemical action begin. You want to work areas that are four square feet or so before moving along operate the buffer at the lowest speed and don’t press down. Let the buffer do the work you are just there to guide it. Now it should be starting to look good. However you will see swirl marks the darker the color the more you will noticeable the swirl marks will be.
8. Hang in there we’re getting near the end. We are going to use a polymer sealant to fill throes swirl marks fill up the voids in the paint and give a gloss. WE ARE NOT GOING TO USE WAX. Wax is bad for paint it has always been bad for paint it was just the best thing they back in the good old days. Today with the advances in polymer technology we can make the paint stronger, longer lasting shiny 3M, Meaguire’s and Finish Kare all make good polymers sealants I use Finish Kare’s Polywipe. Go down to your local automotive paint store and ask them what they carry. Don’t bother to ask at the local parts supply house they just don’t know about this and will likely sell you wax. As far as how it is applied well that is very much like wax apply it with a soft cloth tee shirt material is good old cloth diapers are even better, work it in then let it have up for five or ten minutes. Next, buff with your clean sot foam pad. Work small areas at a time because you don’t want it to harden up it will get very hard and you will have a hard time removing it. Pay special attention to the hood and drivers side door those are the areas people look at closest.
9. Pay attention to the little areas like the edge of the hood and trunk lid get those spots clean before the polymer hardens
10. Pat your self on the back for a job well done.
