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linen beige

Too thick paint jobs

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linen beige

I'm sure everyone has noticed that the original paint jobs on these tractors, or for that matter just about anything factory produced, is WAY thinner than what we end up with when we repaint them. Factory paint films are usually in the 1.5 to 2.5 mil. range, and repaints are seldom less than 4 to 6 mils. One reason for this is that the factories used very high pressure guns with the paint thinned down a lot more than what we use. And they were equipped to force dry them which lessened the number of runs. That made for a thinner coat that still leveled out and looked good, and it saved on paint. For years I have used an airbrush for anything other than hugh jobs such as a whole automobile. The paint needs to be thinned a bit more. It gives a LOT more control for where the paint goes (gets into tight spots great), and the film levels out much better than one from a full sized gun. In fact most films look like wet glass. And because the film is thinner, I use less paint, and it dries much faster, and cures much faster and more completely. It also doesn't weigh near as much and can be used all day with little fatigue. Airbrushes and the small compressors needed for them also cost a lot less than conventional set ups. About the only drawback is that since it uses much less paint and I don't have to mix as much, it can be hard to get accurately downsized mixtures of hardener, etc. I use a Pasche "H" airbrush that is over 20 years old. It is single stage, but has three different tip sizes that will handle patterns (only round patterns but is not a problem) from pencil thin at barely 5 psi to 3 to 4 inches at over 90 psi. I have noticed that the newer versions of this airbrush come with plastic pickup tubes that may not stand up to laquer, but these tubes can be replaced with brass tubing if need be.

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Horse'n Around

I have a question,I see what your saying about using a airbrush and it makes a lot of sense. My question is, could a similar result be obtained by using a detail gun or is a detail gun just a scaled down regular gun? I was a bodyman in auto dealerships for over 20 years but I rarely did the paint work, Im no painter so I honestly dont know any better where painting is concerned. I have a old DeVilbis JGA 502 that Ive always used on my own projects like restoring vintage motocross bikes etc.I have always wondered if using a detail gun would be an option. Ive never owned or used a airbrush. I have noticed that using the DeVilbis on small projects not only results in a heavier application of paint for the most part, but there is a lot of waste as a lot of the paint just gets airborn with the added air pressure.

Would I be better off getting a Airbrush or would a detail gun be ok?I would appreciate your input a lot.Like I said I didnt get to do much painting, so any help you can offer would be greatly appreciated.

Sincerely,

John

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Rideawaysenior

John,

I would think that a detail gun would work just fine as long as the paint is thinned out properly. I've got a regular HVLP gun that I use. I thin the paint a bit more then the recs on the back of the can advise and it comes out just right. Not as good as factory but not too shabby at all..

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KyBlue

Hmmm.. Well I know where your coming from, but I really fail to see the need to paint a whole tractor w/ a Airbrush?

When we do a Resto, even if its just a repaint, usually everything gets painted, and new decals are applied... (least I do it that way). Now I could see worrying about the Mil thickness IF You are trying to keep the OE Decals. Otherwise, there isnt really much point in thinning the paint (which you risk thin spots, runs, etc) or using a airbrush (Again Runs, thin Spots, and Jim your 20 year old air brush might be 'cheap' my last Iwata was just shy of 500.00)

So mix your paint per the can, shoot at the PSI recommended on the Can...and get GOOD EVEN coverage with a slow enough reducer to get good flow out..

and jim if you wanna play with one of these, lemme know I'll bring it by

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Electro12WH

One thing I've noticed about factory paint. I used a propane torch to help remove the pin holding the hitch on my trans. The factory paint did not burn off!

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linen beige

Most detail guns are really more or less the same as the full sized guns with smaller handles and fluid cups. The films they spray are usually no thinner than the full sized versions.

Scott. You imply that I run the risk of thin spots and runs by using an airbrush. Thin spots come from not paying attention. To get a run from an airbrush it almost HAS to be done on purpose. Pashce airbrushes are relatively inexspensive, but they are among the finest quality on the market at any price. I think maybe you envissioned long hours slaving over wide hood panels a quarter inch at a time but you may have missed the part about me being able to use mine for patterns nearly as wide as those from a full sized gun. Using this type airbrush gives a much more uniform finish than even the very best painters can expect from a full sized gun simply because of the finer atomization of the paint droplets and how they level out and build up into the finish film.

Even an average painter can get knockout results from a full sized gun and a little color sanding/rubbing/buffing/glazing/etc., But that same painter can get the same or better results from just spraying with an airbrush and watching it dry.

When things calm down a bit around home we'll have to get together. Maybe we can show each other some spraying tricks.

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KyBlue

Scott. You imply that I run the risk of thin spots and runs by using an airbrush. Thin spots come from not paying attention. To get a run from an airbrush it almost HAS to be done on purpose.

When things calm down a bit around home we'll have to get together. Maybe we can show each other some spraying tricks.

Jim, Yes/No. With a color like red, a thin spot only takes a little missed spot, a variation in your pattern...

Its like Tiger Striping ... while its not hard to prevent, its also super easy to end up with...too little/too much air pressure.. not getting the 50% overlap...etc etc

I'll shoot ya a PM about the home front...

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Operator

As long as the topic is painting, I have a question I'm sure you guys can answer. Powder coating, I'm not really into that type of painting but is it possible to powder coat the hood, fenders, and "tin" pieces then gun paint the rest and get it all to come out matching?

Randy

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linen beige

I don't know much about powder coating shops, but I understand there is a somewhat limited choice of colors. I would suggest having the powder coating done and then have your paint mixed to match that shade.

You may have a bit of trouble matching finish texture, which can affect the eyes perception of shade, but with a little careful gun practice it shouldn't be too hard.

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Horse'n Around

Hmmm.. Well I know where your coming from, but I really fail to see the need to paint a whole tractor w/ a Airbrush?

When we do a Resto, even if its just a repaint, usually everything gets painted, and new decals are applied... (least I do it that way). Now I could see worrying about the Mil thickness IF You are trying to keep the OE Decals. Otherwise, there isnt really much point in thinning the paint (which you risk thin spots, runs, etc) or using a airbrush (Again Runs, thin Spots, and Jim your 20 year old air brush might be 'cheap' my last Iwata was just shy of 500.00)

So mix your paint per the can, shoot at the PSI recommended on the Can...and get GOOD EVEN coverage with a slow enough reducer to get good flow out..

and jim if you wanna play with one of these, lemme know I'll bring it by

One thing I have noticed is that vehicles that I worked on that had thick paint and or primer tended to have much worse chips than those with paint that was applied thinner.Especially on edjes of panels such as doors etc. I dont mean thin as in being skimpy and cheap but I dont know if you have noticed but factory applied paint is pretty chip resistant. I might be way off here but it seems to me that if a surface is properly prepared for paint and the paint is applied correctly, all things being equal paint that is applied thicker will chip easier than paint that is not applied thinner. Like I said in my earlier post I was a bodyman not a painter, but I defineately noticed that vehicles I worked on that had thick layers or applications of paint and or primer usually had far worse chips than those that had the recommended amount of paint applied to the surface. Lets face it, tractors and things like that are subject to and prone to conditions that can cause chips and scratches,so the more you can do to reduce the chance of the paint to be damaged is worth the time and effort. This is my main concern about thick paint. I could very well be totally wrong in my observations here and I am very open to correction and differing opinions.

I am honestly thinking very seriously about buying an airbrush and learning to use for smaller projects like this rather than using a regular gun

John

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Suburban 550

John, your absolutely correct saying the thicker the paint the easier it will chip. I've been a bodyman for over 35 years, not a painter though, but do pick up the HVLP gun from time to time. I redo my tractors using Basecoat/Clearcoat which does increase the thickness even after all of the original paint was stripped. It does increase the millage to the point where some of of the parts are hard to fit back on the tractor such as pedals, footrests, etc. The nice part about the BC/CC it's a pretty durable finish and doesn't chip too easy. As far as a airbrush Jim, I'll have to give it a try. Whatever works out the best for all of you, that's the way to go. I know alot of you do not have the luxury of having the access of a body shop at your disposal but you do it the best way you can. :thumbs:

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linen beige

Whatever works out the best for all of you, that's the way to go.

:thumbs:

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sorekiwi

Hey Jim! Will the airbrush handle primers too? Just wondering if they'll flow something that thick...

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linen beige

Hey Jim! Will the airbrush handle primers too? Just wondering if they'll flow something that thick...

Ahh! This may be where personal preferences are most important. I've used mine to lay down a lot of Dupont primer surfacer (131S and 181S). It does have to be thinned a little more and sprays a thinner coat. On something like round shafts or very small parts the airbrush is good for priming since it limits the pattern to the size of the part and doesn't waste primer on your work surface. But if you're spraying all your larger parts with a sandable primer you may want to use a detail gun or full sized gun with the pattern tightened down. These will lay down the needed thicknesses in fewer coats and surface texture is not a big concern on primer coats that are going to be sanded anyway.

It will spray the heavier viscosity primers but the material cups are so small that when laying down build up coats you'd spend more time refilling the cup than spraying primer.

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PetesPonies

As a painter and automotive restorer . . painting parts with an air brush is crazy. A detail gun is the piece to use. They have much smaller air tips and volume compared to a full size gun. We are talking fluid tips in the .9 range compared to 1.4-1.7 on a full size. Use the proper equipment.

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linen beige

Pete, You completely missed the point and a CRUCIAL detail of my first post. Yes, using a cheap, very fine tip, "t-shirt art" air brush is crazy/stupid/dumb/etc. They just won't handle the viscosity. But using one, such as the Pasche model H with the larger tips give even more fluid/air control than a detail gun and can get into tighter spots than a detail gun can. This model, when equipped with the larger tip, is more of a super detail gun than what most folks think of as a typical airbrush. This is from someone who has done quiet a bit of painting since my first model airplane in '66, with many sizes of gun, on items ranging from body trim on "N" scale (1/160) model autos to full size airplanes.

Just as all carpenters don't use the same size and shape hammers for framing, not all painters can get the same results from a one size fits all gun. I think Ray hit it dead on when he said Whatever works out the best for you is the way to go.

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PetesPonies

So give me something to judge by then. What is the fluid tip size? What size fan can you achieve? What is the pressure at the tip?

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rallysman

I don't know if this stuff is still available, but martin senour nitram paint eliminated the need for base/clear for me. This stuff is tough as nails. It did have a high VOC rate, so I don't know if you can still get it, but over half of the mix was clear and you could smack it with a hammer (when applied on sheet metal) and you could buff it so it was just a dent, not scratched.

It was insane.... I've only used it once, but if I had to paint something again I'd be looking for it.

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Brian1045

I used this one on my 1045. For the money I'll never use anything else. I shot my primer, paint , and clear with it.

http://www.northerntool.com/webapp/wcs/sto...20615_200320615

With these results, even if the primer ruins my tip eventually..I'll just buy another.

100_1195.jpg

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HorseFixer

Interesting :omg: I expect when the stock market opens up on monday Binks, Devilbiss, Sata, and others stock will drop out of sight! :drool:

Really, I would like to try this! If it works It would solve alot of my problems on over spray and mucking up my garage. Jim how is the overspray factor? :drool:

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linen beige

So give me something to judge by then. What is the fluid tip size? What size fan can you achieve? What is the pressure at the tip?

Those questions are answered in my first post, but I'll address those points again.

I don't know how Pasche's tip sizes compare to your gun's tip sizes since pasche doesn't give a decimal size. The medium #3 tip will handle most metallic colors, and thinned primer/surfacer, but the #5 tip works better. The finest #1 WILL clog with metal flake from auto grade metallics.

There is no fan control, only round patterns (unless you distort a tip with pliers.) Because of the ability to spray such fine amounts of fluid I have not run into anything I needed a fan shaped pattern for yet.

I have sprayed details at less than 5 psi with the tip less than 1/16 inch from the surface while barely moving side to side, up to 4 inch and larger round patterns of Centari at over 90 psi. more than a foot away from the surface for highly thinned fog/mist coats or as little as four inches for color coats. Most of the heavier viscosity painting I've done with it has been in the 25-35 psi range, 4-6 inches out at medium pace. I think you'll have a hard time finding a full size gun with such a range of working pressure.

I'll also reiterate a point from my first post. I am not advocating that everyone throw out their favorite paint spraying equipment. I am simply pointing out that most painters lay down a much heavier finish than original when they use larger guns. I'm sure you know of the problems that can come from a finish coat that is just plain too thick. I'm also sure you are aware of the problems that can come from trying to lay down a very thin coat with a gun that just can't atomize the paint finely enough. I have had excellent results by using an airbrush and was only offering information of my success to anyone else who may wish to try it.

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linen beige

Duke, you posted while I was typing. Binks and Devilbiss make airbrushes too. I don't know about Sata. These things are old school high pressure low volume which does spell overspray for full sized equipment. But since the paint volumes are much lower, the atomization much better, etc., if you have your paint mixed right and your pressure/speed/distance right overspray is reduced a lot compared to full sized guns. The smaller patterns are great for smaller parts. One word of caution is in order. With the atomization being so much better the fumes can be a problem. The droplets that do end up as overspray are much finer and can travel a LOT further before settling. As with larger hplv guns if you mix too thin and spray at too high a pressure you WILL paint everything in the shop except the intended part. If you do decide to try using an airbrush don't go out and buy one that is intended strictly for very fine detail work with water based paints. Look for one that can use the larger tips and that has metal (preferably chromed or stainless) fluid pickups and passages. Some of the plastic ones can spray lacquers without harming the airbrush, but they can be easily damaged when you try to clean them. One scratch inside a pickup tube can hold red paint that will ultimately end up in some white paint down the road.

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Suburban 550

Jim, there is no doubt in my mind that you are a very knowledeable man when it comes to painting. After reading alot of your posts everthing you say about tips on body work are things I do in my everyday job. Although I never tried using the airbrush you are talking about, I believe it would work well otherwise you wouldn't be telling us it does. Keep up with your great posting. :omg:

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linen beige

Thanks Ray. But don't make my head swell too much. I've certainly made my fair share of boo-boos.

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PetesPonies

Brian, that Northern gun you link to is a SATA copy. I have a SATA copy that I use for my primers. I'm sure you get a decent top coat from it too. The copies are not all alike. I have used some that were just plain crap. What is not up to snuff if the quality of most of these copies. But only using it once iin a while means it should show you good service. Make sure you clean it well as that is the down fall of most paint guns. If anyone is looking for a decent medium quality gun, get a Devilbiss Finishline. These offer professional atomization in my opinion, for a price is that impossible to beat. I have one I use once in a while. I bought it just because . . . . I have expensive guns I use most of te time, but the Finishline is pulled out on occasion and does damn good.

As for the air brush . . well do as you like guys. A detail gun is the proper tool to use. You can control the flow to the point where over spray is nil. The guns you want to use a HVLP as they offer the least amount of overspray and save a tremendous amount of material over a conventional gun. When spraying clears especially, you need to get enough material down to allow it to flow. You can cut and buff clears afterwards and most are done that way . . but the surface you end with is critical. therefore a drp or uneven surface is practically impossibly to fix. Therefore, I feel the detail is the way to go. You can get a top notch detail gun for about $200 . .make up your own minds.

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