Cutting (Sanding) and Buffing
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From: Gibsonia, PA
Cutting (Sanding) and Buffing
OK boys and girls, I plagiarized some of this beginning text, but it sounded better than what I could write. Can't remember where I got it from. I'm going to chat about cutting and buffing the paint job on your car, this subject is touchy with a lot of people, who think that this step in unnecessary, and this would of course depend on what you want the car to look like when it's completed, a cut and buffed paint job looks completely different from a non cut and buffed paint job, and yes there is a significant risk to your paint job if the person who's doing the cutting and buffing has no experience with the process, it can devastate your new paint job, and you don't need to re-paint your car. If you don't cut and buff your car (or truck) will have a good finish, just like any other factory paint job. If you choose to clear coat, which I didn't yet (again, just a different look) you will have a great, smooth finish with an amazingly deep shine. Without clear coat, you can create a finish that you can stick your arm into up to the elbow and swirl it around. Just for some additional info, the guys at Orange County Choppers don't always clear coat. (At least, this is what I was told by one of the old-timers who was teaching me.) I have painted a number of cars through the years, but until I was taught how to do this, I was never really satisfied and wondered if I shouldn't just pay $3-4k for the paint job. Obviously, if you are looking for an original paint look, you might a well stop here....
I mention Clear Coat a number of times, but the pictures are taken with just color coat (black). I also have assumed that you did the body work well, primed well and block sanded at least with 400 grit if not 800. You can probably get by with just 400 if you put on a heavier wet coat, but you run the risk of runs and orange peel.
Now that we have that out of the way, before you begin the process, you should wash it, and then blow it off with compressed air to remove the excess water, the car can't be clean enough before you do this step, now before I explain the process of cutting and buffing (as taught to me), I'll explain the draw backs of cutting and buffing the car, the reasons why a lot of people don't like to do it.
1. The potential to damage your new paint job.
There are two big reasons why some people shy away from this step, the first reason is that an inexperienced person color sanding the car may go through the clear coat of the paint and in to the color coat,or through the color into the primer, and this means a paint repair on that area where they went through, or a total re-paint of the car "Not Good", the second reason would be that if they don't go through the base coat of the paint there is a chance that the buffer can burn the paint job, when I was learning, I had both of these things happen to me, and neither one of them are fun to fix. P.S. I still have the occasional cut through to the primer
2. Is the extra time ( & $) that it takes to do the cutting and buffing of the car, this can be at least 20-30 hours of added time and more paint.
If your one of those people who is always in a hurry, then it's obvious why you'd hate this process, you absolutely cannot be in a hurry, or those bad things that I talked about earlier will without a doubt happen
Some things to consider if you want to do this -
1. If you don't clear coat, you will want at least 4-7 coats of color paint (or 3-5 clear coat over 2-3 color)
2. You will need a quality buffer (one that is capable of about 600-900 rpm). A dual action wax applicator/buffer just doesn't cut it (that was a pun of some sort).Also a spray bottle (or bucket), soft and hard sanding blocks, sandpaper (see below) and lots of clean soft rags, one or two levels of buffing compound and swirl remover (just a finer grit compound).
Buffer - 250 to ~ 2500 rpm
Spray bottle with slightly soapy water /4x6 block (hard rubber)
The Color Sanding Process
If you care, you should mask areas that you don't want compound to get on. Next you should get a bucket with water and dish soap in it, or if you feel more at home using a spray bottle load it with water and dish soap also (my preference- P.S. the soap adds some surfactants which keep the water from beading and help carry any particles away from your contact area), and then your going to want to have some 400 (not much), 800 or 1000 grit wet sand paper to start with, and you'll be working up to 2000 grit by the time this process is done, first you'll need to spray the working down with water, and it does not matter where you start to color sand the car, it's just where you feel comfortable starting from, this is a long process, so don't get in a hurry, if you do it will be at the expense of you new paint job, OK now you'll want to have a decent selection of sanding blocks, a cut and buff is designed to create a smooth appearance over the entire surface of the car, and if it's done right it does a very good job of that.
This picture shows the raw paint job. It looks OK, nice shine and reflection, but does have a little orange peel in places and some specs of dust. No runs, but that hasn't always been the case.
Check the area you are working with to see if you have any runs, nasty orange peel, big flecks of dirt or other big anomalies (fancy word) in your paint. This is the only time you would use 400 grit. Use it carefully and just take off the top of the imperfection.
Now spray down the immediate area and choose any appropriate sanding block and wet it down as well. Use the 400 if you need to, but sanding the area is reserved for the 800 or 1000 grit. I usually use a 4-6" hard flat block on the large flat surfaces of the car, you never want to sand or buff the crown of any panel on your car, I use a 4-6" round hard rubber block in the curved areas on the panels, at the first it will look as if it's not doing anything (if you clear coated), it will turn whitish with just color. (take my word it is smoothing the clear coat on your car, when you color sand your clear coat you need to pay serious attention to what you are doing, cutting and buffing will remove any dust or runs from you paint job and smooth the surface to a brilliant deep shine.)
This is a close up while I was sanding with the 800 grit. The really black areas are small imperfections and deeper orange peel areas. Keep working the area with the 800 or 1000 grit. This is BLACK Paint!
Note: When you start to sand the car, if your using a spray bottle you'll spray some of the contents from the bottle on to your painted surface, and then you'll begin to sand the coat with 800 or 1000 grit wet paper, make sure that you sand only in one direction, as it will be easier to buff out in the end, do not press hard on the block, let the sand paper do the work, and if you hear a squeaking sound stop now, and run some water over your sanding block and the surface of the car, a squeaking sound means that you have a piece of balled up clear coat or color under the block, or dirt, in either case, you do not want it there so clean the block and surface of the car.
When your sanding your paint with the 800 or 1000 grit paper, your looking for the entire surface of the car to have a smooth and dull appearance, remember that you still have to sand the clear coat with 1500 and 2000 grit sand paper, so it does not need to be perfect at this stage of the game, just make sure that you've sanded the entire surface of the car before you move on to the next stage.
This is of the finished 800 grit cut. Yes, It is actually black!
Now you'll repeat the same process with 1500 grit wet paper, and then 2000 grit wet paper, after you have done this, you done color sanding or cutting the clear coat. If using clear coat, you don't ever want to see the color of your base coat on the sanding block, this means that you have gone through the clear coat, so pay attention to what you are doing.
This is of the finished 2000 grit cut. You should actuall begin to see some reflection in the paint. The 1500 and 2000 grit sandings go much faster than the 800-1000. Be sure to spray and wipe away dust with a clean soft rag frequently! Note: Unwashed
The Buffing Process:
P.S. I Posted the before as a link, but thought I would regurgitate it.
I mention Clear Coat a number of times, but the pictures are taken with just color coat (black). I also have assumed that you did the body work well, primed well and block sanded at least with 400 grit if not 800. You can probably get by with just 400 if you put on a heavier wet coat, but you run the risk of runs and orange peel.
Now that we have that out of the way, before you begin the process, you should wash it, and then blow it off with compressed air to remove the excess water, the car can't be clean enough before you do this step, now before I explain the process of cutting and buffing (as taught to me), I'll explain the draw backs of cutting and buffing the car, the reasons why a lot of people don't like to do it.
1. The potential to damage your new paint job.
There are two big reasons why some people shy away from this step, the first reason is that an inexperienced person color sanding the car may go through the clear coat of the paint and in to the color coat,or through the color into the primer, and this means a paint repair on that area where they went through, or a total re-paint of the car "Not Good", the second reason would be that if they don't go through the base coat of the paint there is a chance that the buffer can burn the paint job, when I was learning, I had both of these things happen to me, and neither one of them are fun to fix. P.S. I still have the occasional cut through to the primer
2. Is the extra time ( & $) that it takes to do the cutting and buffing of the car, this can be at least 20-30 hours of added time and more paint.
If your one of those people who is always in a hurry, then it's obvious why you'd hate this process, you absolutely cannot be in a hurry, or those bad things that I talked about earlier will without a doubt happen
Some things to consider if you want to do this -
1. If you don't clear coat, you will want at least 4-7 coats of color paint (or 3-5 clear coat over 2-3 color)
2. You will need a quality buffer (one that is capable of about 600-900 rpm). A dual action wax applicator/buffer just doesn't cut it (that was a pun of some sort).Also a spray bottle (or bucket), soft and hard sanding blocks, sandpaper (see below) and lots of clean soft rags, one or two levels of buffing compound and swirl remover (just a finer grit compound).
Buffer - 250 to ~ 2500 rpm
Spray bottle with slightly soapy water /4x6 block (hard rubber)
If you care, you should mask areas that you don't want compound to get on. Next you should get a bucket with water and dish soap in it, or if you feel more at home using a spray bottle load it with water and dish soap also (my preference- P.S. the soap adds some surfactants which keep the water from beading and help carry any particles away from your contact area), and then your going to want to have some 400 (not much), 800 or 1000 grit wet sand paper to start with, and you'll be working up to 2000 grit by the time this process is done, first you'll need to spray the working down with water, and it does not matter where you start to color sand the car, it's just where you feel comfortable starting from, this is a long process, so don't get in a hurry, if you do it will be at the expense of you new paint job, OK now you'll want to have a decent selection of sanding blocks, a cut and buff is designed to create a smooth appearance over the entire surface of the car, and if it's done right it does a very good job of that.
This picture shows the raw paint job. It looks OK, nice shine and reflection, but does have a little orange peel in places and some specs of dust. No runs, but that hasn't always been the case.
Check the area you are working with to see if you have any runs, nasty orange peel, big flecks of dirt or other big anomalies (fancy word) in your paint. This is the only time you would use 400 grit. Use it carefully and just take off the top of the imperfection.
Now spray down the immediate area and choose any appropriate sanding block and wet it down as well. Use the 400 if you need to, but sanding the area is reserved for the 800 or 1000 grit. I usually use a 4-6" hard flat block on the large flat surfaces of the car, you never want to sand or buff the crown of any panel on your car, I use a 4-6" round hard rubber block in the curved areas on the panels, at the first it will look as if it's not doing anything (if you clear coated), it will turn whitish with just color. (take my word it is smoothing the clear coat on your car, when you color sand your clear coat you need to pay serious attention to what you are doing, cutting and buffing will remove any dust or runs from you paint job and smooth the surface to a brilliant deep shine.)
This is a close up while I was sanding with the 800 grit. The really black areas are small imperfections and deeper orange peel areas. Keep working the area with the 800 or 1000 grit. This is BLACK Paint!
Note: When you start to sand the car, if your using a spray bottle you'll spray some of the contents from the bottle on to your painted surface, and then you'll begin to sand the coat with 800 or 1000 grit wet paper, make sure that you sand only in one direction, as it will be easier to buff out in the end, do not press hard on the block, let the sand paper do the work, and if you hear a squeaking sound stop now, and run some water over your sanding block and the surface of the car, a squeaking sound means that you have a piece of balled up clear coat or color under the block, or dirt, in either case, you do not want it there so clean the block and surface of the car.
When your sanding your paint with the 800 or 1000 grit paper, your looking for the entire surface of the car to have a smooth and dull appearance, remember that you still have to sand the clear coat with 1500 and 2000 grit sand paper, so it does not need to be perfect at this stage of the game, just make sure that you've sanded the entire surface of the car before you move on to the next stage.
This is of the finished 800 grit cut. Yes, It is actually black!
Now you'll repeat the same process with 1500 grit wet paper, and then 2000 grit wet paper, after you have done this, you done color sanding or cutting the clear coat. If using clear coat, you don't ever want to see the color of your base coat on the sanding block, this means that you have gone through the clear coat, so pay attention to what you are doing.
This is of the finished 2000 grit cut. You should actuall begin to see some reflection in the paint. The 1500 and 2000 grit sandings go much faster than the 800-1000. Be sure to spray and wipe away dust with a clean soft rag frequently! Note: Unwashed
Now that the cutting or color sanding process is complete on your car, you'll want to wash all the wet sanding residue from the car, wet sanding will leave a white powder type residue on the car, and you don't want to put the buffer to this residue, so make sure that you wash the entire car again before you get started with the buffer. Set the speed to about 800 rpm or medium speed on the speed selector, this may seem a bit slow, but you have less of a chance of burning the paint job with it set at a lower speed, and you can use water to help cool the paint as you buff the car if you want to, you'll be starting with a heavy buffing compound and working all the way down to a swirl remover, yet another long process.
Get you courage up and your patience, and get ready to dive in head first, there is no changing your mind now.
Now put a little dab of the heavy cutting compound on the surface of the car where you want to start buffing the paint, and also I almost forgot, this needs to be done inside a garage, the sun will cause big problem with this process, what your going to do is put a lambs wool pad on the buffer, and then pull the buffer trigger and begin to buff the heavy cutting compound off of the car, you'll notice it starting to bring the shine up on the surface of the paint, when you run out of the heavy compound on the surface just keep adding more and moving in slow circular motions until the entire surface is buffed with the heavy compound.
This picture shows the gloss (reflection) after the buffing was completed, but before the swirl remover buffing was performed.
You'll repeat this process with medium-light cutting compound, and last but not least swirl remover. When you change compounds you'll want to have the appropriate pads for each step in the process, and make sure that you clean all the pads as they will get clogged with compound, you can can a pad cleaning tool from your local auto paint retailer.
This picture shows the gloss (reflection) after the swirl buffing was completed. The camera flash caught a little of the compound residue that I didn't fully get off
I take way too many breaks and smoke too many cigarettes, but the entire process on the door and lower front cowl took about 6 hours. Probably 4.5 -5 hrs. if you were a little more dedicated and your hands and arms didn't occasionally need to recover from sanding!
Any tight spaces, sharp edges and curves should be hand buffed. The machine will cut through the paint on these exposed areas.
I'm getting ready to cut and buff my front fenders and hood before I ghost flame them. Probably will clear to hide the flame edges and deepen the shine. The same process will apply. I'm not a paint guy, just someone tired of doing a crappy job.
I'll do some picts as I progress.
Get you courage up and your patience, and get ready to dive in head first, there is no changing your mind now.
Now put a little dab of the heavy cutting compound on the surface of the car where you want to start buffing the paint, and also I almost forgot, this needs to be done inside a garage, the sun will cause big problem with this process, what your going to do is put a lambs wool pad on the buffer, and then pull the buffer trigger and begin to buff the heavy cutting compound off of the car, you'll notice it starting to bring the shine up on the surface of the paint, when you run out of the heavy compound on the surface just keep adding more and moving in slow circular motions until the entire surface is buffed with the heavy compound.
This picture shows the gloss (reflection) after the buffing was completed, but before the swirl remover buffing was performed.
You'll repeat this process with medium-light cutting compound, and last but not least swirl remover. When you change compounds you'll want to have the appropriate pads for each step in the process, and make sure that you clean all the pads as they will get clogged with compound, you can can a pad cleaning tool from your local auto paint retailer.
This picture shows the gloss (reflection) after the swirl buffing was completed. The camera flash caught a little of the compound residue that I didn't fully get off
I take way too many breaks and smoke too many cigarettes, but the entire process on the door and lower front cowl took about 6 hours. Probably 4.5 -5 hrs. if you were a little more dedicated and your hands and arms didn't occasionally need to recover from sanding!
Any tight spaces, sharp edges and curves should be hand buffed. The machine will cut through the paint on these exposed areas.
I'm getting ready to cut and buff my front fenders and hood before I ghost flame them. Probably will clear to hide the flame edges and deepen the shine. The same process will apply. I'm not a paint guy, just someone tired of doing a crappy job.
I'll do some picts as I progress.
P.S. I Posted the before as a link, but thought I would regurgitate it.
Posting Guru
Joined: Jul 2006
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From: Westminster,Md
Thank's for taking the time..and having the patience, to share your experiences.
The pic's really do help,..as I've learned the hardway what to look for when wet-sanding my own 'drive-way' jobs, this should help alot of folks out.Great post!
The pic's really do help,..as I've learned the hardway what to look for when wet-sanding my own 'drive-way' jobs, this should help alot of folks out.Great post!
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