Well, it has been decades since you have bought your trusty car, and its body certainly shows it. We understand that your car is in tip-top shape. But don’t you feel like giving it a new look now and then?
To give you car a new outlook, what’s more accessible than to paint it in a new color? And no matter how daunting this might sound, if you can do an excellent job of scrapping the old painting with patience, the rest of the task will become as easy as pie.
If you are worried that you will do a poor job removing the old paint and rust, do not. In this article, we are here to help you learn how to sand a car to bare metal with easy guidance.
You might wonder, ‘what great travesty will happen if I repaint my car without sanding anyway? It’s not like people will be able to look underneath the new coating.
Then we will say that you have some lacking in understanding the real purpose behind the paint-stripping of the car.
People shave off the old paint and rust of the car and downgrade it to bare metal, not to make the painting preparation look tiring, but to ensure that the paint will stick for a long time.
Without proper prior sanding, the new painting will lack a solid foothold to establish itself. As a result, it will peel off the old paint’s glossy surface in a short time.
What’s more, you never know whether your car’s body has begun to rust underneath the old paint full of tiny cracks. Better to be sure than to be sorry!
As we all heard in at least once in our life, prior preparation is essential for success. So, you better not skip sanding your car to bare metal out of laziness unless you want to get a poor result.
Therefore, for better understanding, let’s have a look at some of the grits you can use:
Which Sandpaper Grit You Should Use For Bare Metal Sanding?
You know the most sensible way to have a perfect sanding is to use sandpaper. But here you need to choose the preferable grit according to your work.
The grit you need wholly depends on the surface you are sanding; also the result you are after. Another considering thing is the types of abrasive material this paper comes from.
For sanding metal and finishing, silicon carbide paper (wet/dry paper) is the most suitable option. This sandpaper wears the best and resists the heat produced during bulk sanding.
However, come to grit’s point. Sandpapers come along with a vast range of grit number as from 12 to 2500. The larger the grit, the more delicate it is. So, which one do you exactly need; finer or coarser?
Let’s see the ranges of sandpaper grit at a glance.
a) 12 to 80 Grit (Coarse Grit)
This range of grit number is considered as the coarse sandpaper, which is usually best for stripping, bulk sanding and shaping. Whether you’re sanding wood, you need an one of this range.
But, you can’t use these sandpaper grits while sanding a bare metal as coarser sandpapers are likely to leave large scratches on the surface.
b) 100 to 280 Grit (Intermediate Grit)
Medium grit sandpapers are used to remove and smooth the marks or scratch that the coarse grit sandpapers leave. Larger grits are better for sanding bare metal for the first time.
For removing any layer of paint from metal choosing these grits can be a better option.
c) 280 to 600 Grit ( Fine Grain)
This range of sandpaper is preferable for most of the finishing work of sanding metal. Before painting, you should use the larger grit to give it a final finish.
If there is any rough area spotted along the surface that is being sanded, the grit more than 300 will smooth this In a better way than the lower’s.
d) Above 800 Grit (Extra Fine)
For eliminating scratch or marks, these grit aren’t acceptable. When you need an extra finishing after the painting is done, you should apply these grits at that time.
Some times, you experience significant setbacks if minor challenges occur, such as any dirt and hair, can be stuck under the painted surface. Applying these extra fine-grit sandpaper will let you to won’t face those problems anymore.
Well, Now The Question Is, Which Grit Exactly Should You Apply While Sanding The Car?
We will suggest you use 220 to 400 grit sandpaper when you are sanding by hand. You should use at least two grits for a different purpose.
The first thing is to remove the layers of paint and lacquer. Then, to smooth finally it for painting.
While removing the paint from bare metal, 220 grit will be a wise choice. But, it will leave scratches in your car surface.
For putting off that marks and giving it a final smooth skin before painting, you can apply 400 grit sandpaper as well.
However, You can use more than 800 grit sandpaper after all the painting has done, if you need.
7 Best Ways to Sand a Car to Bare Metal [with cleaning & finishing tips]:
Now that you have understood, we better move on to more critical parts of the article.
Now, before we begin talking on how to sand a car to bare metal, let us take some moments to familiarize ourselves with the popular methods of removing car paint down to the bare metal. Here are the 7 Best Ways to Remove Car Paint to Bare Metal:
1) Using a Dual Action Sander
If you are not going to scrape away the paint out of the entire car surface or dislike the idea of using chemicals, you can try using a power sander. It is noisier and requires more work, but very useful.
A power sander is a machine used for sanding. Just attach a suitable sanding paper, a cloth for collecting the removed paint, and rub it over the surface area for cleaning the paint. Easy enough.
We suggest you use Dual Action Sander as it’s essential to use in an auto body sanding. This sander will prepare your car surface before and after painting with an ultra-smooth sanding.
Also, smoothly sanding the corners and tight space seemingly tricky in the auto body sanding process without a DA sander.
So, how to sand with a DA sander? Please wait. It’s coming later.
2) Using Hand sanding block with sandpaper [grit 220-400]
The oldest method for sanding is using sandpapers. Hand sanding is entirely manual, unlike the previous two procedures and the most labour and time-consuming method.
But it is ideal for cleaning up small areas or removing single-layered painting. https://amzn.to/2VYqyFn
Here, you need sandpaper grits 220-400 along with a sanding block. The sanding block will provide a rigid and flat surface behind your sandpaper.
You shouldn’t go for sanding a flat surface without a sanding block as it would leave a chance to make a wave under the sandpaper without having no block. Need the best hand sanding tool? Check here: Top 8 Best Sanding Block for Auto Body sanding [Reviews & Buying Guide]
All you need is to keep the block horizontally and move it to X shaped pattern while you are sanding. And, make sure that you are leading each stroke only with the larger edge of the block.
3) Sanding Nooks and Crannies, or a Curved Surface:
How to apply this sanding block to sand car body’s nooks and crannies, curved surface – you are wondering?
Well, Simply, you need to warp the sandpaper around the block. But for sanding a curved surface, you should select the appropriate block that must be a comfortable and flexible one.
Also, you can shape and cut the block size according to your need. Or, if possible, you can make your sanding block by cutting a rigid foam that can be applied to sanding nooks and curved surfaces with appreciate sandpaper grits.
4) Sanding Steps for Painting a Car:
As we have mentioned, sanding by hand is the traditional method for removing car paint. Despite being laborious and time-consuming, this car painting method is the cheapest.
Just be careful in your hand movements and be patient, and it should work wonderfully.
But before you begin, remember to put on these safety features.
A dust mask
Protective gloves, and
Remember, your safety is most important. Well, here the tools you need to complete the sanding steps.
Dual Action (DA) Sander
Car body filler
Now that you are ready, let’s begin.
Step 1 > Start sanding with 220 grit sandpaper:
Take a piece of sandpaper designed for removing paint from cars. It is best to start with a slightly coarser paper, like 220-sandpaper at the beginning.
Step 2: Sand with a sponge or sand block
Please attach the sandpaper to a sponge. With slight pressure, apply it in circular motions in the painted area and remove the paint.
Step 3: Clean it up.
After this stage is over, clean up the surface with a towel or a microfiber cloth if available. Remember to check out for any leftover residue with bare hands.
Need some more to do!
Step 4: Try 400-grit sandpaper.
Don’t relax now. You are not finished yet. Another step of sanding is still undone. For this second-stage sanding, use a slightly less coarse paper, like 400-grit sandpaper.
Step 5: Use car body filler if needed
Even after sanding is done, you may notice some small imperfections in the car body that need repair with body filler. Use a body filler to sparingly and to smooth imperfections.
You can also use glazing putties for filling small pinholes, or if the need is minor, that would be more effective than a normal body filler.
Step 6: Clean again:
Again, it is time for cleaning. Use soap and water for this stage. The time for using only a cloth is over.
Done? Just a little more left- the easiest part. Hose down the entire area for final cleaning, and you are done with the sanding. Congratulations!
5) Strip Car Paint with Liquid Deglosser/Paint Stripper:
The easiest method requiring the least amount of labour for stripping away paint from the metal surface is using a paint deglosser. It is one kind of chemical solution, otherwise known as liquid sandpaper.
Just clean the surface, apply the solution with a cloth as per instruction, and wait for it to take effect. This method is perfect if you are to remove paint from the entire body of the car.
But before you apply it, take necessary measures to protect the glasses and joints so that they don’t come into contact with the chemical to avoid possible complications.
Frankly, using this method would cut your time. Even then, we won’t recommend you to go for this. Why?
Because it’s not such an effective method to find the best output, you need to apply a lot of security while using this liquid chemical. As examples
You can’t work with it in a close environment as it produces fumes.
Paint stripper can damage the rubber and glasses of your car; need to maintain extra security.
After the first application, some layers of paint might come off.
A little sanding is required after applying the deglosser.
6) Guide on How to Clean Bare Metal before Painting:
As we have said before, the prior preparations are the most challenging part of repainting a vehicle. Now that you are done removing the paint and dirt from the car’s body let us move on to the next part.
Before you start on your little victory, dance, stop! We are not done yet. Just look at the stubborn grease and grime sticking onto the metal, however, to get lost!
Clean up with Alcohol or Vinegar or Soap & water:
You have managed to remove the outer paint shell from the car’s body and expose the bare metal underneath. Now it is time for you to clean up the car surface properly.
To clean up the sanding car surface of the metal, you can follow multiple methods. Using rubbing alcohol is the easiest ways to remove the grease and stains.
But be careful! To ensure that the alcohol completely evaporates before you start with applying a coat of a different solution. Otherwise, it will just be a disaster in the making.
If you don’t have any alcohol to clean up the car, you can also use vinegar. It will work just like alcohol, and the aftercare is just the same as well. But if you like to work simple, you can stick to the old school soap and water cleaning.
After you are done, clean it up again with water. It needs more time and effort, but the procedure is cost-effective and straightforward.
7) Guide on How to Sand a Car for Primer
Now that you have removed the old paint from the metal body and cleaned it well, your new paint will surely get a more comfortable hold over the metal.
But that does not mean that you should apply the paint directly over the sanded bare metal. NEVER do that!
a) Apply a Primer:
Before you apply a fresh coat of paint, you should apply primer over the metal first. First, you should lightly sand over the metal carefully to let the primer get the best possible hold over the metal surface.
b. No Need to Finish Too Smoothly
Use a less coarse sanding paper for the sanding. Don’t try to make the finishing too smooth, though. A slightly rough finish will help your primer to get the best hold over the metal possible.
c. Sand The Primer Coat After Making It Dry.
Now it is time to add a suitable primer. After you carefully add a coat of appropriate metal primer, give it time to dry out. Then lightly sand over the primer coating again.
This step is significant. Why? Because this exact sanding will let your paint coats to get some stable holding over the metal body. So, now your car is in tip-top shape for some serious painting.
d.Don’t Use Epoxy
By the way, no matter what you do, don’t use epoxy as a primer. Epoxy is a sealing primer to protect the car’s metal body when it remains unpainted for a more extended period. It is not something to be sanded immediately after its application.
So, what do you think? Do you think our article has helped you to learn how to sand a car to bare metal well? If you think it had, then what are you waiting for? The procedure may seem complicated, but the key lies in thorough cleaning. Trust in yourself. We believe you will be able to sand and paint the car properly, wishing a beautiful finish!
Hi, I am Rogers Weber, the man behind Solvesonic. I am a mechanical engineer. I use many kinds of tools almost every day at my workplace. I love to write about tools, home improvement, and DIYs. I enjoy helping people to solve their problems through my website.