How to Fix Rust Spots On a Car

How to Fix Rust Spots On a Car
I drive a 1985 VW Golf (diesel), and it's in pretty good condition for being 21 years old. There are three spots on the front left fender that have rust on them. Someone had hit the car and the paint came off, so it became rusty. These spots are not only an eye sore, but they are sure to spread in the salty Nebraska winters.

My goal in fixing these was function, and not so much glamour. The car is kind of a beater, so I wasn't too concerned with making it look perfect. As long as the rust was gone, it would look better, and I wouldn't lose a fender.
 
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Step 1Assess the Situation/ Remove Wheel

Assess the Situation/ Remove Wheel
Having never done this, or any other body work on a car, it took me a little longer to figure out what exactly I was going to do. My original plan was to take the entire fender off, but after inspecting it, that would be too much of a hassle and would require me to disassemble a lot of the front of the car.

Instead, I jacked the car up then I pulled the wheel. I unscrewed the plastic thing protecting the wheel well and set it off to the side. That gave me really good access to see up behind the sheet metal on the car. I was originally going to pound out the dent on the upper part of the fender, but space was tight and I couldn't easily do it. Having the wheel well open will help when I'm grinding and painting.
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86 comments
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Sep 9, 2006. 4:39 PMspinach_dip says:
looks pretty good. I no longer care too much about appearance, because I drive beaters, but whenever I would grind out rust and prime and paint, the rust would return in that same spot within a year. I think the grinding removes all the galvnizing. Although I haven't done any cosmetic bodywork with it, I've had good luck on other things with primer that says it containes zinc. They are also known as cold galvnizing compounds.
Sep 13, 2011. 6:56 PMhmakori says:
Did you try magic oil.
Sep 13, 2011. 6:53 PMhmakori says:
I read on another site mercedessource .com and found out that there is magic paint that can stop the rusting right away. Can you try?
Aug 19, 2011. 1:18 PMEric Sullivan says:
Galvafroid for instance
Jul 2, 2010. 6:51 PMskimmo says:
is there an acids that remove rust, i have a chainmail shirt that i need to de rust and it will that to long to polish every ring
Sep 8, 2011. 9:27 AMLorddrake says:
a non chemical way to remove the rust is to put the chainmail shirt into a sealable large container (5 gallon bucket with a lid is great for this) and add some fine sand (in a pinch you could use sifted playground sand) or other abrasive compound.

put the lid on tight, turn the bucket on it's side, and roll the bucket to aggitate the shirt and the abrasive.

after you get the shirt cleaned remove it from the bucket, clean it off, oil it well.
Apr 29, 2011. 11:07 AMjperez128 says:
Rust-Oleum/8 oz. rust stripper
Jul 25, 2010. 4:05 PMbassbindevil says:
There's also phosphoric acid; you should find some form of it in the auto body supplies section, maybe under a brand name like Ospho or metal prep. Citric acid also eats rust; you can get that in dry form at home brewing supply stores. And, finally, sulphated molasses, from the feed store. Google these things along with rust and you'll find more information.
Jul 7, 2010. 1:19 PMJerryMopar says:
Muratic Acid, get it at a hardware store or farm supply
Jul 6, 2011. 12:23 AMrobbs says:
I need a bit of advice with my rust spots. I have them on the roof and hood. The rust hasn't eaten into the metal yet. So, I need to hurry up before it does. Can someone give me the procedures? I plan on hand painting with roller. Its a '91 Buick Skylark. Not quite a "beater," but its getting there. BTW, I'm a female taking this task on! Thanks for the input!
Jul 22, 2011. 3:54 PMac1D says:
Usually, this work:
Sand the rust using normal sand paper, start with something like 150 and end with 2000 (these are the size of the sand on the sand paper)
Then spray paint it.
May 8, 2011. 12:25 PMBrianJone5 says:
For your first body work, this is excellent. Certainly better than my first attempt.

Aerosols can't deliver the flake, so you'll never get a match. If your mask was outside the paint area (i.e new paint over good paint around the repair) you could soften the line with rubbing compound and a microfiber cloth.

One thing to add to your next repair is a degreaser. This is a solvent that removes all the wax and grease and road grime everywhere you want the paint to stick. They sell it where they sell the paint.

My second suggestion would be to 'feather out' your sanding. Try to sand each layer to an inch-wide stripe. This gives you less of a step to deal with in filler and paint. Change to a less aggressive abrasive and smooth it all out.

Most importantly though, you have stopped the rust in its tracks, and from 20 feet, no-one can see the repair. BTW with older cars, one way of assessing their state is in feet: "Its a 20-footer" explains how close you have to get to see noticeable defects. As you might expect, a 10-footer would be in really good shape.
Jul 13, 2010. 2:28 AMLeviMan_2001 says:
I wouldn't recommend using a grinder, use a wire wheel.
May 8, 2011. 12:07 PMBrianJone5 says:
The sandblaster wheel is fine for this job. Its not a solid grinding disc that I think you suspected it was, its overlapping pie segments of 'sanding' material.
Apr 29, 2011. 11:07 AMjperez128 says:
You could have used Rust-Oleum/8 oz. rust stripper to get some of the rust off also.
http://www.autozone.com/autozone/accessories/Rust-Oleum-8-oz-rust-stripper/_/N-25uj?itemIdentifier=660016&_requestid=550873
Nov 12, 2010. 3:09 AMbraydensucks says:
why rust must be removed?
because rust slowly desolves your metal and destories the pain job along with the back metal now i dont know about you but having square cut outs of replaces metal looks worse then a crap paint job
so do it right
hand sandpaper it
then use hole filller prefeerd for cars and undercoast
then hand sandit again.... and then use a sander
until smooth and roughed
put under coat on usualy white
then get car coulour then clear coat
this will make it very pro,d and not like bad or noticable
Apr 7, 2011. 8:12 PMjcarrier1 says:
Do you know how to speak or write? desolves? Destories? Pain job? Replaces metal? Prefeerd? Undercoast? Usualy? Car coulour? This will make it very pro,d? Go back to kindergarten dude
Apr 17, 2011. 4:41 PMsaintofkillerz says:
Troll! Btw, you didn't put a period at the end of your last sentence. Give useful advice, or go away.
Aug 26, 2010. 7:49 PMTheDirtyBosnian says:
I have a 1986 F150 and to fix the rust spots I just put duct tape over them and then paint over that, because I'm to lazy to actually tend to the rust spots
Aug 31, 2010. 9:20 PMNot_a_Clue says:
so how is the duct tape working cuz i got rust rotted holes in my 1986 chevy s10
Sep 2, 2010. 10:57 AMTheDirtyBosnian says:
the duct tape holds but it is slightly noticeable but if u just glance at it you dont really notice it but also my rust spots are on the bottom of the cars fender and side skirts so its not like people just stare at those parts of the car anyway.
Sep 24, 2006. 2:23 AMkporter says:
I need some advice; I think my girlfriend has been cheating on me. At first her phone would ring and I would go to answer it and she'd grab it from me and say its none of my business. Then I answered it once and this guy said hello and then hung up. And she keeps going out at night and she wont tell me where she goes, and when she gets back she walks from around the block as if someone dropped her off and didnt want to be seen. Anyways, last night, I wanted to see who was dropping her off, so I drove around the corner and parked in a driveway and hid behind my car and waited. There, I noticed a little rust on the inner wheel well of my car, so would you recommend taking it into an autobody shop, or just buying the spray on stuff and doing it myself?
Jul 2, 2010. 8:18 AMrebel48 says:
Well thank her or you would have never found the rust!What does all that have to do with your rust? Get a new girlfriend or pay more attention to her and your car! Go to any auto parts store for canned paint since it want show they will recommend paint repair products. As for the first of your I need advice those are life lessons learn as you go
Aug 27, 2008. 7:22 PMGoat Chaser says:
I have my eye on a 69 GTO. It had a vinyl top and there are some little holses in the roof from the rust. The wind shield and and back window look unstable. The rest of the car is solid and was a CA car. Can anyone give me advise on the cancerous roof? Can it be fixed and stabilized? I can send pictues. any comments are welcome since I am new to this muscle car thing.
Jul 2, 2010. 8:11 AMrebel48 says:
all cars are painted completely at the factory the top must have damage which allowed water under the vinyl top. The water under the top probably collected under the chrome trim around the windows causing rusting. Removing the trim and old top repair the body damage replace the top and trim. A good upholstery person specializing in vinly tops would be your best shot. or repair and repaint leave vinyl top off.
Jul 2, 2010. 1:57 AMbartpeeters says:
Always heartwarming to see someone showing so much care and respect for a small old car and not just taking part of our disposable society.
Mar 28, 2007. 3:35 PMbluebelle says:
i was just wondering what to do if the rust is all the way through. can you use bondo for that? the spot is about 14 cm by 8 cm.
Jun 15, 2009. 1:49 AMone_fake_user says:
By a tube of rust converter. It converts iron oxide back into a quasi metal. It is a good idea to use it on any rusty area that you are not going to physically cut out and weld a new patch back into. If you don't the rust will most likely come back fairly quickly. Rust is like cancer, even the smallest amount of rust can turn into a horrible tumor. For instance before doing this step of the instructable I would still use rust converter to ensure there was absolutely no rust left. It isn't all that expensive either so it is a worth while investment. Hope this helps.
Jun 15, 2009. 1:50 AMone_fake_user says:
correction "Buy a tub of"
Jun 29, 2010. 3:23 PMstinna2 says:
you don't actually need much the rust converter stuff is pretty thin and goes a long way
Jun 28, 2010. 3:38 PMzack247 says:
hey dont forget that pacthing the rust will help keep your car on the road longer.
Jun 25, 2010. 10:43 PMleandrop7 says:
paint the whole fender so there will be differences in painting!
Jan 20, 2010. 7:36 AMduh-man says:
yeah....  its not a sports car...................just a old car..............................
May 20, 2010. 11:41 AMDirtMcGurt says:
 yea.......some people take care of their possessions...............and don't want them rusting into the ground...................

plus VW diesel golf has way more character than some 80s Joe dirt mullet mobile Camero/transam/firebird
Mar 12, 2008. 9:28 AMhellZEN says:
Kudos on your resourcefulness!!! I did AutoBody work back in the day... When things were slow, we did rust/rot work. BTW, they don't galvanize body metal, at least back then - the paint doesn't stick to it. Regarding rerusting .... If you can TOTALLY get to bare metal, you should be ok. If pits remain, you need to treat with a dab of rust treatment. There are two kinds that come to mind 1) a coating that has phosphoric acid and possibly tannic acid like the rustoleum rust reformer stuff or similar product that chemically transforms the rust (iron oxide) into stable Iron phosphate with a coating to seal it (don't sand before priming). 2) products that use oxalic acid and possibly tannic acid, again with some kind of coating left behind. Finally, the old man always told me to "metal prep' the bare metal to remove any residual flakes from grinding and lightly etch the metal, leaving behind a light coating containing zinc. Before priming, we would generally pull the tape back and "feather" the edges on the original paint, so that the new primer comes up level with the old paint. For the color coat, you can lightly scuff the area to allow a fade of the new color into the old. It just takes some 400 or 600 grit paper and a couple of extra minutes.
Apr 1, 2010. 11:17 AMTom83 says:
I've just started work on removing some rust spots on my car...  However, I get these distinct lines when I pull the tape off...  What do you mean by "feather"-ing the edges??  I'm really stumped on how to blend the new paint into the old paint...  Also do you have any suggestions on how to make the new paint "pop" the clear coat doesn't seem to give it the same shine, I've also tried buffing it as well...  Thanks!
Apr 1, 2010. 2:56 PMhellZEN says:
 The paint is not going to be a 100% match in terms of texture or color.  Factory, paint and sprayers are different.  So you have to do some blending.  
 1 BLENDING THE SURFACE - Feathering or "feather edging" means, that you sand it out so that you can see the layers as you move away from the repair.   What you are doing is creating a very gradual ramp in the paint from the bare metal to the original paint surface.  This will be filled with primer and maybe even a light coat of putty.   You will then level off the repair fine paper and a block so that the primer is exactly level with the old paint.  Check with your hand to make sure there are no edges - Your eyes will not be sensitive enough for this.  When you are done , you are ready for your base color coat.  Sometimes I used to put the base color and the final color coat all in one shot.
2 BLENDING THE COLOR AND TEXTURE -   Of course the whole area has to be prepped so that paint will stick when it lands.  If there is a natural divider, like a crease in the body, or a molding, that is a good place to cut the new work from the original. There should be no tape near the repair, unless it is an edge in the body.  After the Primer has been covered, you mist the color to blend with the original .   I used to thin the paint out and go out some distance from the repair.  It may be easier to clearcoat the entire area than to attempt to blend , but that is a judgement call.  The old clearcoat may be more pebbly or have micro scratches that will make it stand out.  This might make some of it easier to see:
www.bukisa.com/videos/185975_how-to-feather-edge-paint


May 20, 2010. 11:36 AMDirtMcGurt says:
 I've found the best thing you can do to make this step easier is GOOD filler.  We used some stuff called All metal which is really good for fine work as it sets up hard as rock so you can feather it better.  Crappier filler/bondo won't feather well and you will end up with lines between the edge of filler and the original surface.
Dec 13, 2009. 10:11 AMHADJISTYLLIS says:
 this is what i need to do on my ride.
THANKS!!!!!!!!!!!
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