AirBrush Paint Chip Repair?

A

anaxagoras

New member
Has anyone other than Brad B. used airbrushing to repair paint chips? I saw his write up and I really want to try it.



I've got some nasty chips on my fender, the previous owner of my car rolled the fenders and the paint is all chipped where they were rolled. Since these are such large chips I would think i'd have better luck using an air brush to cover such a large area and not make it look like ***.



My hood and bumper are also peppered with paint chips. Of course since it's a black car with a light color primer should i say "Salted" with paint chips? For these small chips I think i'd be better just using the tooth pick method for touch up paint.



But back to my topic. Has anyone done this? Brad B. reccomends using a paasche single action, but it seems that a double action would be better and give you more control. Does anyone have any thoughts/opinions on this?



I'll try and get some pics of the paint chips for you guys.







**EDIT** I changed David B. to Brad B.
 
Here's a picture of a spot on one of the fenders that I want to airbrush. Both fenders have spots similar to this, but this is the worst spot.



As you can see there is some surface rust. I already sanded a little bit off, it doesn't go down deep at all. If nothing else i want to hurry up and do this to keep it from seriously rusting and turning into a bigger headache.
 

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This is one of the few good paintbrush paint repair threads I have read. There just aren't that many people patient and skilled enough. It does provide some hope though.



http://autopia.org/forum/car-detailing/43937-chip-repair-three-simple-weeks.html



Good luck with your repair. He gives pretty good details on how he went through it. There are also some good hints on how to avoid the hard edge further down the thread (rounded over edges for taping down).



Edit: Sorry, you said David B. posted the repair info, and I thought you were talking about a different article (Brad B. wrote this one), but based on the reference to the type of airbrush that you cited, you must have read the same writeup.
 
That was the thread I was reffering to. Brad B. not David B. That's where I got my inspiration to want to try this.



Thanks though.
 
Alright, I did a little researching on airbrushes, and while I haven't done it, I think I know why he is recommending a single action airbrush.



airbrushes



The difference being a single action you can control how much air is being applied. The amount of paint is set by a screw knob, and only varies based on the air flow



With the dual action you can control how much air AND how much paint are being applied on the fly, from an art point of view, this is ideal, because it is tedious and honestly impractical to vary the amount of paint by stopping your stroke and turning a screw knob.



This sounds like for paint repair it would likewise give more control, but do you want to be able to adjust amount of paint on the fly? I really don't believe you would because it gives you more room for error. Also this is not an artistic endeavor. Ideally you want to be able to apply the CORRECT amount of paint, and you want to set it beforehand so you can't accidentally apply too much or too little (or at least make it easier on yourself to get it right). You will want to change it based on results (I imagine doing adjustments and testing it on a surface other than the car prior to using it), but you won't want to do it on the fly, because you are trying to do something repeatable, as opposed to artistic. As I see it you want smooth even coats of paint. The masking/holes are to take care of the edges, not controling paint flow seperately.



If you are quite talented at airbrushing I'm sure either will work, but the dual action has to be more difficult to learn, and less consistent in paint aplication, especially for someone with little experience. So based on learning curve, cost of equipment, and the fact that you really want consistent amounts of paint, it really does seem to lend itself to the single action airbrush that he recommended.
 
Well written clear and concise. LOL.



I now see exactly why single action is reccomended for this application.



Thanks!



I went to a hobby shop the other day and they tried to sell me a dual action stating that it would be better for this application. I'm going to order on ebay anyways since it's cheaper.



If I do a halfway decent job at this I'll be sure to take pictures and provide a writeup.
 
Brad B's thread is about the only one I've seen on using an airbrush, and elsdragon314 explained the advantage of a single stage airbrush very well. I revisited Brad's thread a couple of weeks ago and decided to give it a try sometime this winter. Since I'm not in a rush I'll probably just put the airbrush on my Christmas list, plus there are some other uses I think I can find for one.



As far as your chips/scratches go I'd at least try to get the rust cleaned off and some primer put on them until you get around to actually touching them up. Griots has a small spot sanding tool that works pretty well for small jobs like this. Here is a link:



Griot's Garage 1-800-345-5789 - Misc Car Care



The picture isn't very good, and I've seen almost the same thing here locally at an auto paint supply store. This link will give you a little better idea of what they look like:



Prep Pen Spot Sanding Pen



Good luck and keep us posted!
 
Thanks, I ordered the sanding spot tool from griots, along with some other toys. I had to use a lot of restraint though... high limit credit cards are way too tempting, lol.
 
A few sorta-random thoughts:



Thesanding pens go through their fiberglass "erasers" pretty fast. Google "MicroMark", their catalog has refills (and lots of other cool stuff including airbrushes, artist's brushes, etc.).



My dble action Paasche can be used single action, but I've never tried it. Heh heh, gotta admit I've never even used it *at all* but I keep planning to :o



I did use single action Paasche airbrushes a *LOT* back in the day (scale modeling at a fairly serious level) and I can assure you that you really *DO* want a quality airbrush; cheap ones are junk.



But getting autopaint repairs to blendsmoothly is tricky; I tried it a few times a long way back and it never worked out very well for me.



Give it a try; I suspect you'll have even *more* appreciation for how well Brad's repairs turned out after you've tried it yourself.



Shoot test patterns on a piece of something, you'll get the air/paint/etc. settings sorted out quicker than you might think.



Remember that you'll need thinner to get the paint/primer right for the airbrush.



I'd sand *way* back from the current area of operation, go at least 1/4"-3/8" beyond what looks OK. Even after you use the sanding pen, you'd better treat/rust-convert the area, don't just trust a primer to work.
 
Figures right after I order an airbrush I read another post (Accumulator)... not that I'm complaining, I like posts.



I ended up going with a paasche single action kit from ebay. 1 of the things i read is for thicker (read automotive paints) you want an airbrush that mixes the paint externally vs internally, as internal mixing is more likely to clog the brush. So i probably still would have gotten the single action even after reading the above post.



I went to paintscratch.com and ordered a 2oz paint kit, I would think its sufficent? I have about 4 gashes like the one pictured in my initial post (though that is definitely the worst one). Hopefully I don't waste too much on test pieces before i figure things out.



2oz clear, 2 oz base, 2 oz primer, and 2 oz of thinner. I also got somer cleaner shtuff to prep the area.



Now, why should i use a rust converter. What exactly does a rust converter do on a more technical level? and do i primer over the rust converter or use it in place of?



And i couldn't find refills for the sanding eraser on that site.



Thx.
 
Two ounces should be a good start, especially since you'll be thinning it down to spray.



If you do a keyword search for refills on the "MicroMark" site you'll find them (thanks for that tip Accumulator, it's a pretty cool site):



Micro-Mark: The Small Tool Specialists | Tools and Supplies for Building Scale Models



A rust converter like POR 15 or the Eastwood Rust Encapsulator converts (or encapsulates) rust and seals the surface. Useful if any traces of rust might remain. I've only used them for larger (mostly unseen) areas but I don't think either product requires a primer before top coating.



Don't be too discouraged if the airbrush doesn't lend itself well to all of your touch-ups. You can always fall back on the artist brush, wet-sand, and polish method or something like the Langka system if needed. I wasn't too impressed with the results I got from the Langka kit last year, but I may give it another shot on some very small spots.



I usually have better luck doing a traditional touch-up, wet-sand, and polish, but I'll be trying an airbrush for a couple of places so I'm curious to see how well it works out for you.
 
I think this may be too big an area for the Langka system to be effective? Also, I am going to second either a rust converter, or an etching primer, and taking off some of the good paint to make sure you got it, rust is an insidious thing.



The problem with the touch-up wet sanding and polishing is that it would be nearly impossible to get a metallic flake to look right in the repair. From your picture I can't tell if there is a flake in it though. The airbrush will take work, but we know it can give good results.



Also, very good point on the single action mixing externally, that is probably very important for good results in this case, as automotive paint sprayers have larger openings and can tolerate paints that use larger particles, and we are talking the color pigments alone, not even considering what a large flake would do. In an internally mixing airbrush, clogging could be an issue.



Also, reading the airbrush websites, it looks like you will need to thin the paint much more than you would for a regular sprayer, testing will be your friend. It looks like Brian B. did 50/50 paint and thinner, but he was also spraying at a rather high 65 PSI. If you thinned it further you could probably run at a lower PSI, it might help atomize the paint better.



Document what you do, take a couple pictures and let us know how it goes! There are a lot of people out there who could benefit from this.
 
anaxagoras said:
...I ended up going with a paasche single action kit ....
Click to expand...
Excellent choice. You can’t go wrong with a Paasche. I’ve had my H1 for over thirty years and love it. I have a Binks too. It’s also an excellent brush but I prefer the Paasche.





anaxagoras said:
... 1 of the things i read is for thicker (read automotive paints) you want an airbrush that mixes the paint externally vs internally, as internal mixing is more likely to clog the brush. So i probably still would have gotten the single action even after reading the above post.....
Click to expand...
Any brush will clog if you don’t keep it clean or if you attempt to shoot paints that are too thick.



There are tips and needles available for a wide range of paint viscosities. Auto paints, even at the normal consistency for shooting from a big gun, are about in the middle. As long as you have an appropriate tip and needle they’ll shoot fine. (I’ve shot primer through mine.) Yeah, you’ll tend to thin them a little more for the brush, but not all that much more.



Some people clean their brushes the quick and dirty way, by simply shooting thinner though them. Of course, some people clog their guns to hell too. I clean my gun thoroughly every time I use it. The fluid handling bits of a Paasche strip down very easily and quickly. It’s easy to keep your gun operating perfectly.







Eliot Ness said:
...A rust converter like POR 15 or the Eastwood Rust Encapsulator converts (or encapsulates) rust and seals the surface. Useful if any traces of rust might remain. ....
Click to expand...
I partially disagree.



Eastwood Rust Encapsulator and POR 15 are coatings, or perhaps they should be called converter/coating because they include conversion ingredients in addition to their coating components.



Rust converters that are only rust converters and not coatings are also commonly available. They chemically change the rust from its normal form to a stable form that won’t continue to grow. They also stabilize the base metal so new rust won’t form. But they don’t leave a coating like paint or primer behind. They prepare the surface for a coating.





PC.
 
the other pc- Heh heh, I'd forgotten the "H1" designation until you mentioned it! I got mine around '73, lost track of it in the 1980s. Those things are great as long as you don't abuse the needle part. Not sure which tip/needle/whatever you'd need to shoot automotive paint though :think:



anaxagoras said:
I ended up going with a paasche single action kit from ebay..



I went to paintscratch.com and ordered a 2oz paint kit, I would think its sufficent? ..
Click to expand...



The S/A Paasche is *VERY* good and very easy to use. Be sure to use the right tip for the paint in question.



That should be enough paint. The airbrush doesn't use much, just be careful about how much you thin/mix for the airbrush so you're not being wasteful.



Now, why should i use a rust converter. What exactly does a rust converter do on a more technical level? and do i primer over the rust converter or use it in place of?
Click to expand...



It's *very* hard to get every microscopic bit of rust removed,even with a metal prep/acid wash product. A converter is a good bit of added insurance. Some hold up incredibly well even if not topcoated (I had some stay rust-free for over a decade!) but most do not. Some converters need primer over top, others don't. Sorry, I've only used the discontinued 3M Rust Avenger (absolutely *GREAT* stuff) and the Eastwood converter (not so impressive IME) so I dunno about all the different ones on the market. I guess I'd say to prime over the converter.



The Rust Encapsulator is soluable with regard to lacquer solvents, and that can make for issues when you apply touchup paint over top of it. You gotta "fog" the paint on very thin until you build up a layer of paint that seals the Encapsulator.



Oh, and Langka can work over a pretty large area, but I think I'd lean towards wetsanding instead.
 
Accumulator said:
It's *very* hard to get every microscopic bit of rust removed,even with a metal prep/acid wash product. A converter is a good bit of added insurance. Some hold up incredibly well even if not topcoated (I had some stay rust-free for over a decade!) but most do not. Some converters need primer over top, others don't. Sorry, I've only used the discontinued 3M Rust Avenger (absolutely *GREAT* stuff) and the Eastwood converter (not so impressive IME) so I dunno about all the different ones on the market. I guess I'd say to prime over the converter.



The Rust Encapsulator is soluable with regard to lacquer solvents, and that can make for issues when you apply touchup paint over top of it. You gotta "fog" the paint on very thin until you build up a layer of paint that seals the Encapsulator.
Click to expand...





I called up PaintScratch and had them add a 2 oz bottle of rust converter in with my order, so hopefully they use something decent.



for the paasche, I got the complete set. It comes with all 3 tips (1,3,5), but I intend on using the medium #3 tip as Brad B. used. I also ordered 3 x 1oz glass bottles, some extra hose and a moisture filter. I intent on trying to recreate what Brad did as best my abilities allow, since obviously he was on to something. I'll keep clear in one bottle, basecoat in the other, and finally some thinner in another bottle to clean the gun out between bottles.



Interesting point about "fog"ing the paint on very thin when using a converter. I'll be sure to do that. Hopefully everything i order will arrive by the weekend, although I'm sure I'll be waiting on a package from one vendor or another. Otherwise I have to wait for next week's 3 day weekend to do this.



The products I will be using are all recommended to be used above 50 F, I intend on shining my halogen work lights right on the repair to add a little extra heat into the situation. I will also start with the smallest chips first and work my way up to the big one. Hopefully by the time I get to it I'll have picked up a few things.
 
Accumulator said:
the other pc- Heh heh, I'd forgotten the "H1" designation until you mentioned it! I got mine around '73, lost track of it in the 1980s. Those things are great as long as you don't abuse the needle part. ...
Click to expand...
An excellent point.



Probably the easiest part to abuse is the tip. That’s the cone shaped nozzle that screws down onto the needle to regulate paint flow. It’s a fine, precision orifice and it’s made of fairly thin metal.



There’s absolutely no reason to ever tighten the tip down onto the needle but that’s what people tend to do and it causes the tip to flair out, messing up the spray pattern. You only need to gently screw it down until it just barely touches the needle to stop paint flow.



That’s not even something you ever really need to do anyway if you think about. What’s the point of a spray gun that doesn’t flow paint? All you really need to do is screw it down until it’s barely flowing. That’s the minimum you’d ever use and you’ll just open it up from there. If it clogs, clear it by running a little thinner through it, not screwing down the tip to push the clog off.



The needles themselves are also very precise and can get banged up if you’re careless. You just need to handle it carefully while it’s disassembled and then don’t bash the base of the tip into it when re-assembling them together.



.pdf of parts breakdown for Paashe H & HS brushes





PC.
 
the other PC- Good point about the cones...Yeah, as a young, impatient guy I messed up my share of H1 cones; don't clear them by poking carelessly with steel needles, and don't drop them on concrete floors :o



anaxagoras said:
Interesting point about "fog"ing the paint on very thin when using a converter. I'll be sure to do that..
Click to expand...



Note that you *only* need to do that if the underlying stuff is likely to be affected by whatever you're spraying. This is a big issue with Eastwood's Rust Encapsulator (unless you top it with enamel) but I don't expect it'll be a issue at all with what you're using. I bet you don't have to worry about it at all. Go for a good fairly wet spray pattern.



Watch that the halogen light doesn't flash the paint too fast as in while it's still atomized in the air.
 
A guy here in my area has made a business out of it. He goes around to all the car dealers in the area repairing paint chips with an air brush on used cars. On my last car I got a large chip on my door. It was really noticable and that is why I had it repaired. He charged me $100.00 to repair it and after he did you couldn't tell where the chip had been. The small dings that aren't noticable I don't think its worth it to goto all that trouble.
 
muscleknight said:
A guy here in my area has made a business out of it.. He charged me $100.00..[for a repair] and after he did you couldn't tell where the chip had been..
Click to expand...



I've heard of people offering that service but I've never met anybody who does it (other than my regular painter). Lucky you, finding somebody good! Glad to hear it turned out so nice.
 
muscleknight said:
A guy here in my area has made a business out of it. He goes around to all the car dealers in the area repairing paint chips with an air brush on used cars. On my last car I got a large chip on my door. It was really noticable and that is why I had it repaired. He charged me $100.00 to repair it and after he did you couldn't tell where the chip had been. The small dings that aren't noticable I don't think its worth it to goto all that trouble.
Click to expand...



This gives me some more hope, even though i'm a total novice. I've been obsessively reading up as much as I can on car painting and air brushing.



I don't think I'm going to get everything i ordered by tomorrow, so looks like I'm going to be busy on turkey day, of course having 4 days to do this might no be so bad.
 
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