Introduction: Taking Out Little Dents

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To fix a single dent (like the one pictured), it is probably not worth the time and paperwork it takes to fill out the insurance claim. Besides doing it your is easy enough --the tools won't cost much, and the instructions won't make your head spin.

You can bang out that dent, fill those nicks, and refinish that paint job with a body hammer and dolly, a sander with a 36-grit disc to remove paint, a putty knife and body filler squeegees to apply filler, a bodyworking file ("cheese grater") to level the filler, a stroke sander to smooth it, an air compressor and spray gun to apply primer/surfacer/paint, and a buffer to shine it all up. Thanks to today's body repair materials-better paints, improved fillers and two-part primer/surfacers-bodywork and painting to a mirrorlike finish has never been easier to do in your own shop.

Step 1: Bang It Out

To remove a dent, first gain access to the back side of the body panel by removing items like headlight buckets, inner fenders, door panels and interior trim. Then, place a dolly on the outside of the dent and then hammer on the inside of the dent, striking the metal against the dolly. The key is to go slowly and work around the circumference of the dent, banging it out until it lies just below the undamaged area. After the dent is out, put the dolly on the inside of the dent, then tap the area surrounding the outside of the dent to knock in any high spots.

Step 2: Prep and Apply Filler

When you're sure all the sheetmetal is just slightly below the surface of the surrounding area, use a disc sander with 36-grit paper to remove all paint and primer from the dent and surrounding area. This will give the body filler a rough surface (called tooth) to hang on to once it has hardened. After thoroughly mixing the filler with hardener, smooth it on the damaged area with a plastic filler applicator. The filler semihardens in 10 to 15 minutes to the consistency of cheddar cheese.

Step 3: Smooth and Sand Down the Filler

At this point it's easy to smooth with a body file. Use the file to knock the filler down so it is slightly higher than the finished repair will be. After about 15 to 30 minutes, the filler becomes hard.At this point you can use a hand or air-powered stroke sander with 80-grit paper to bring the filler down to the level of the body. If you see any bright, shiny metal spots in or around the filler, those areas are high. Use the pointed (pick) end of a body hammer to tap them in slightly, then refill and resand.

Step 4: Prime and Surface

Before the repaired area can be painted, scratches, pits and waves must be completely removed or they'll show up as reflections. A primer/surfacer forms a thick layer of material over the area, which is then sanded down to make the repair smooth and level. Two-part primer/surfacers, consisting of the primer and a hardening agent, allow a thick layer to be applied over the repair in only one or two coats. After a half-hour of drying the primer is ready for sanding.

(Warning! Before applying any primer or paint, be sure to wear a respirator rated for organic solvents.)

Step 5: Contrast Paint the Primer/Surfacer

Before you sand, apply a light mist of black lacquer from a spray can over the repaired area. This contrast coating will reveal imperfections that will disappear as you sand. Make sure there is adequate ventilation, and also make sure that pilot lights and other flame sources in the general area are turned off.

Step 6: Prep for Paint

To sand the primer, use a rubber sanding block and 400-grit waterproof sand paper. The trick is to sand lightly while frequently dipping the paper in a bucket of water to keep it clean. When all of the black contrast coat has disappeared, the repaired area is finished. Then clean and prepare the surface surrounding the repair to accept paint then wipe the entire panel with a solvent-based wax remover. Now, wetsand the area again to be painted with 600-grit waterproof sandpaper. If you're going to blend the paint into the original paint, make sure to sand an area larger than the area where you will be applying the paint. Thoroughly rinse the area, let it dry and then wipe again with wax remover. Mask off adjacent panels, then cover nearby wheels and major portions of the car with painter's plastic sheeting to shield it from overspray.

Step 7: Paint

Mix the basecoat with the appropriate amount and type of solvent according to the maker's instructions. Before spraying, gently wipe the area to be painted with a tack rag, then spray the panel or repaired area. If you are blending, apply only enough basecoat to cover the repaired area, then taper off as you move away from the repair. After the basecoat has dried thoroughly, you'll notice its finish is quite dull. This is so the clearcoat will adhere tightly. Do not sand the basecoat before applying the clearcoat. After mixing the clearcoat with hardener, according to the manufacturer's instructions, apply a medium wet coat and let it flash dry 5 minutes or so before applying a second coat. After letting the clearcoat dry for an hour, remove all masking tape. Then wait one day before polishing.

Step 8: Polish

Chances are the finish already looks pretty good. But to make it flawless, it pays to color-sand and polish the entire repair. Use 1500-grit sandpaper to flatten the finish, followed by rubbing compound to remove the scratches left by the sandpaper. Finish up with polishing compound to make the finish flawless. After polishing, wait one month to apply wax.

Comments

author
bleachworthy (author)2007-12-08

keep in mind that a body shop will charge you hundreds to do this. personally, I hate bondo with a passion, when it ages, it will get deformed, warp, chip, and eventually fall off. if you're going to do a job, do it right, by cutting out the dent, welding in a new patch, and sanding it smooth, then proceed from step 4. it's much more difficult, and risky, but it will last forever.

author
jkl78 (author)bleachworthy2014-07-12

Overkill Much?

author
strangebike (author)2012-07-18

I know this instructable is old and all but did you try just pushing it out with the butt of your hand. Has worked for me in the past. Of course the damage done by the wife taking the gate post to work with her might take a little more. Thanks a lot fella nicely done ible

author
yo man (author)2009-05-13

dude what is lacquer?

author
strangebike (author)yo man2012-07-18

Lacquer is a transparent top coat that seals the paint underneath from the outside world and often uses u.v. inhibitors to make it last longer. It can also be tinted (coloured) with different colours to add to paint effects and is the reason why metal flek paint is so pretty.
I hope this helps

author
strayturk (author)2012-06-21

If the paint is not marred, use a dry ice to remove the dent instead.

http://www.wisebread.com/remove-car-dents-quickly-and-cheaply

author
triumphman (author)2012-05-29

I thought this was about "taking out little chicks" ! You know, for dinner or a drink! Oops!

author
id301 (author)2012-04-21

Good write up, however this was really excessive. If you want to remove a dent like this all you have to do is get a toilet plunger and some water, wet both the plunger and the surface, put the plunger over the dent and quickly pull out. Voila, easy and can be done in 5 minutes, this seems really excessive.

author
chaitanyak (author)id3012012-04-29

Hmm will try that

author
heartlessangel7 (author)2011-02-24

Harbor Freight tools is gawd in the eyes a budget DIYer.

author
macmundi (author)2010-09-09

I used an angle grinder too (just like this illustration) I changed it into a buffing pad, the rev was too fast; burnt the paint.

author
lampajoo (author)2008-07-05

that's way too much work for a little dent

author
adam395 (author)lampajoo2010-08-15

Hey, some folks are loving in the care they give to their cars, others aren't. I sit in the garage for hours every now and then touching up and making repairs to keep it looking new, and I've got an '04 Civic. Nothing fancy, but it's still something you adore. I loved this write-up. Laid it out very nicely and will help me solve that ding I have on my rear right panel.

author
WhirringWheels (author)2009-07-06

A paintless dent repair guy could make that look almost new for about $150. I've become a believer!

author
rouge180 (author)2009-05-16

I found the entire write up informative and made it seem a lot easier that I thought it was going to be. It seems as though it's about 90% prep and 10% paint. Thanks. I'm going to try this.

author
attilam (author)2008-10-11

It's best to use a matt black paint from a can, not a gloss. Gloss will clog your sandpaper when you try to sand it back...

author
Derin (author)attilam2009-01-19

You can sand dome rubber when it gets clogged.Credit to TimAnderson for the idea of sanding rubber.

author
Jalakahops (author)2008-02-20

Yeah, do it yourself as long as you have all of those professional tools.

author

A man w/o tools....is a girl....or a convenience store clerk.

author
WolfVecho (author)2008-10-11

Thank you this will be a big help as my car was peppered by hail the night I went to pick it up and it wasn't insured...

author
SirWalterRich (author)2008-05-13

Yeah. I will be performing this real soon. Somebody hit my car, while I was parked in a parking lot. This process doesn't appear to be too complicated. Now all I need is a body kit instructable.

author
picbuck (author)2008-04-27

I've done this in a shadetree-mechanic way, and it's really not that big a deal. The PopMechanics guys broke it down into many small steps, which is good for learning but makes it look hard. Hands-on, it's really not so tough. ...except for the part about setting up an auto paint shop in your back yard. This can be very tough. But the parts store can probably supply spray cans in your paint color, matching with the VIN. By the way, the Bondo people say filler is good for up to one-eighth inch thickness, and no more. It's for smoothing the surface, which is does very well. But not for filling up large dents, they have to be hammered approximately smoothish.

author

Very nice job, I didn't know putty could be applied.

author
MacUser (author)2007-08-02

Holy Sheet Mon! Very interesting... but a little too involved for my tastes! Got an instructable on engine rebuilding? I bet it's just as easy!

author
static (author)MacUser2007-09-20

The "HP" series of automotive books http://www.hrpworld.com/index.cfm?form_cat_id=356&action=category have to be the best "instructables" on engine rebuilding I have ever seen. They have books an many engines, so you can get one tailored to your job. While rebuilding an engine isn't difficult, it requires attention to details, if the body repair sounds too involved for your tastes, an engine rebuild may be as well.

author
Lord_Hate (author)MacUser2007-08-02

The process isn't all that difficult, I have done it a couple of times. (not on my car) The worst part, or the one that most people would have difficulty doing would be the shaping of the Bondo or cheese grating of it. Rebuilding a engine is quite easy to do in you garage, and the tools aren't that expensive, it isn't easy or cheap if you have to bore a cylinder though. Building an engine from scratch is difficult and time consuming, even before you order any parts. Anyway nice Instructable.

author
junisponds (author)2007-09-13

You can used a can of Compressed Air and a hair dryer. See the video here:
http://www.toologics.com/News/Top_Ten_Lists/10_%27Unusual_Fixes%27_Using_Power_Tools_20070725239.html

author
dentsinger (author)junisponds2007-09-17

That vid was amazing, but does it work on hail damage sized dents?

author
junisponds (author)dentsinger2007-09-17

I'm not sure but it's cheap enough to try.

author
pfred1 (author)2007-08-07

Now I always thought the square side of a body hammer was for edges. That, and are you hammering on, or hammering off of the dolly? How do you deal with panel thinning, stretching, and puckering?

Really, if you don't know what you are doing with hammers and dollys you are probably just better off drilling out the panel and using a slap hammer on it. The holes help the Bondo grip the panel anyways. That, and fenders are like $50 at the junkyard.

You might find one of these useful in your future bodywork endeavours:

http://images.google.com/images?hl=en&q=shrinking+hammer&um=1&sa=N&tab=wi

author
prizepatrol (author)2007-08-02

I read somewhere, maybe here, that you can use dry ice to remove small dings. According to what I read, you repeatedly rub dry ice onto the ding until it virtually disappears. You'll need an insulated glove or towel to hold the ice. I can buy dry ice at my local market, so I may try that on a couple of my dings. But the dent you pictured, I doubt dry ice would work, but it might be worth a try.

author
pfred1 (author)prizepatrol2007-08-07

Well there is a friction disc that works on the heat differential factor to raise metal, like a cookie sheet warping in your oven sort of a deal. There is a specific pattern that must be followed in order to move the metal in the desired direction too. I'd imagine dry ice is just the reverse. Though steel gets funny when you drive its temp down too low personally I'd go with a friction disc with the heat differential method myself. Even a strong enough buffer might be able to heat the metal sufficiently to cause it to raise, and you'd have the added benefit of shiny paint in the area too.

author
kitschykat (author)2007-08-03

What is a "dolly"? (step 1)

author
ggariepy (author)kitschykat2007-08-05

See the image at http://ec1.images-amazon.com/images/I/21gTppXsaiL._AA160_.jpg

The square-shaped objects on the left are "dollies" -- heavy pieces of metal with different curved surfaces that are held against a piece of sheetmetal and used with the hammers to reform it to the desired shape.

Be careful using body dollies. It is relatively easy with the hammer-on dolly technique in this instructable to make the sheetmetal thinner than it started out. This can result in a surface that "oil cans" easily. DAMHIK.

--Geoff

author
ezrdr (author)2007-08-03

Great Instructable!!! I have most of the tools, just never knew the best process. I've got a few dents and dings in my pick-up that I'm going to fix now and save the $1500.00 quoted by a local body shop. Even if I had to buy all the tools, paint and bondo, I could save over $800.00. Thanks for the assistance!

author
momule (author)2007-08-02

Your instructable is well written and it's obvious that you've done this before. My only observation is that the total cost of the tools (air compressor, paint gun, buffer etc) will end up being about as expensive as having the Dent Doctor do the job or maybe even a body shop to do it like you instruct. And cheap tools are a real waste of money. I believe I'll stick to using a professional or just learn to live with the occasional dent or ding.

author
jeff (author)momule2007-08-02

Well momule, there's plenty of makers on this site who have all these tools already (or would like an excuse to buy them), or don't live near a 'Dent Doctor' et al, or can't afford to be without their car for the time it takes a pro to fix it. Or - ahem - just want to DIYD! Personally, I think it's fantastic that PM is posting on this site - the synergism pretty much insures I'll keep my subscription current.

author
numberandom (author)2007-08-02

Awesome instructable! Excellent pictures.

author
Vortex-5 (author)2007-08-02

Very nice very professional.... But I've painted in the past painting and paint matching isn't exactly easy I'd have to leave that one to the professionals. (it's worse if paint fades or if you have to repaint an entire panel.... which can be the size of the car.

author
Josho (author)2007-07-31

Same car as mine, same alloys. Whats yours like? Mines a purple/grey colour 3.3i V6.

author
theRIAA (author)2007-07-30

did you try dry ice... ?

author
saites2001 (author)2007-07-30

About how long does this process take? It seems a bit lengthy, though extremely effective.

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