Urethane paint, need the basics.

[Chas SCR]

Dave is right, Also just to add till you get use to working with the stuff "Pick a brand" and stay with it and work with that till you get use to it. Do not mix brands with PPG Clear with Du Pont harder for there clear. Some brands will have a hardner and a reducer for with there paint and clear and some will not.

Also you can put the clear over any kind of paint (enamels and lacquers) and so on.

I can not speak for PPG or HOK paints but the Du Pont paints are very thin paints.. You want to make sure you have your body work done right as when you paint it, It will show every little thing wrong. Also the Clear is the same as it magnify every little problem.

Edited August 25, 2010 by Chas SCR

[ScrappyJ]

I normally sit on the sidelines, but in this case, I have to add my two cents.

I would agree that everyone has their own way of painting (and building). To me, you build how you want to as long as you're satisfied with your results. However, as most of the top-level builders in this post have said, if you want stunning results there is typically a process, skill level and certain level of patience in getting there (again, as long as you're happy with your results, that's what matters).

My painting, although still not nearly where I would like it to be, has come a very long way since being back into the hobby. There are many folks on here that have explained good points and tips on painting, but I have only worked with two of the names mentioned (Bob Downie and Dave Morton). If it weren't for those two, the painting and polishing of the paint on my projects would be less than satisifying to me.

Of late, Dave Morton has been the key person in helping me with my painting and polishing and as for his work, I have not seen (in person) better finishes than what I see in his work. Again, the patience and time factor weighs heavily. For instance, on the green, '50 P-up truck he posted, he spent several hours (may have even been days) at a two-day layover (Dave's a pilot) he had in Orlando, polishing on just one fender of that truck. When I went to visit him and saw it in person, it was ubelievable. I normally spend less than that time on an entire polishing session. Now that is patience!

It doesn't matter whether it is painting or building, IMHO, planning, patience and execution are critical to a well-built project. Again, if you want it to be really nice, I think patience is the most critical. There are some guys that can put out high-quality projects quickly and consistently, but I would say that those folks have honed their skills over time and multiple projects.

I've learned that no matter how much you think you know (and for some people, how good you think you are), there are always things to learn and remove for improvement. I continue to learn so much through so many people (somtimes the most un-suspecting) and am just greatful for the exposure and opportunity to continue building my skills.

Again, one of these people is my good friend Dave Morton. Thanks for the personal coaching, Dave and for continuing to offer your help and advice to so many !

Edited August 26, 2010 by ScrappyJ

[Steve Keck]

I normally sit on the sidelines, but in this case, I have to add my two cents.

I continue to learn so much through so many people (somtimes the most un-suspecting) and am just greatful for the exposure and opportunity to continue building my skills.

Again, one of these people is my good friend Dave Morton. Thanks for the personal coaching, Dave and for continuing to offer your help and advice to so many !

I find it hard to expound at length on mosts subject. In short, I'm a man of few words. And, when someone says it best I don't try to say it another way.

So, what you said, Scrappy!

But, the glowing accolades? I thought the primaries were over. Is David running for office?LOL!

Steve

Edited August 26, 2010 by Steve Keck

[Karmodeler2]

I find it hard to expound at length on mosts subject. In short, I'm a man of few words. And, when someone says it best I don't try to say it another way.

So, what you said, Scrappy!

But, the glowing accolades? I thought the primaries were over. Is David running for office?LOL!

Steve

The primaries are over....I lost.....but support is......well support! I welcome it.....even if I'm a loser!!!!

Thanks Dirk for the nice comments. I appreciate it and you have done the same for me in the machining realm to bring my game up to a better level and I thank you for that.

While I like you as a friend, I don't like competing against you cause you bring it hard and strong and it makes me a better modeler to step up and run with you. THanks for all the motivation!!

David

And Keck,

Don't make me come out there and "re-arrange" things in your home!!!

David

[Steve Keck]

And Keck,

Don't make me come out there and "re-arrange" things in your home!!!

David

Bring it on, Big Boy! Maybe you can shorten my learning curve.

Steve

[slapshot]

David,

I shot my hood with concept DCU2021 @ two to one the hardener @ one & the reducer @ three to one. After the application it looked great.I was pleased to say the least. I then placed it in the dehydrator for six hours @ 105 degrees. When I removed it i noticed three small imperfections that looked like small vertical bubbles.I know that it is not trash due to the great pains that I went through to avoid such matters. Funny thing is that you have to hold the hood up to the light @ angles to see the imperfections.This was my first time using urethane clears & next time I will use the 4-1-& double up on my reducer.Also the air pressure on my airbrush was set @ 35.lbs.Any thoughts on the air type bubbles.Thanks in advance Gary.

[Steve Keck]

Gary,

I've encountered bubbles in a urethane product I no longer use. The bubbles were the result of not allowing the clear to gas out between coats. The bubbles form from the solvents and were trapped between coats. My experience waiting longer(within reason) than the flash times indicated on the product sheet does not affect the results.

From the looks of your results in doesn't appear you are doing anything else wrong.

David is the 2021 expert so I will yield the floor to him.

Steve

[Karmodeler2]

David,

I shot my hood with concept DCU2021 @ two to one the hardener @ one & the reducer @ three to one. After the application it looked great.I was pleased to say the least. I then placed it in the dehydrator for six hours @ 105 degrees. When I removed it i noticed three small imperfections that looked like small vertical bubbles.I know that it is not trash due to the great pains that I went through to avoid such matters. Funny thing is that you have to hold the hood up to the light @ angles to see the imperfections.This was my first time using urethane clears & next time I will use the 4-1-& double up on my reducer.Also the air pressure on my airbrush was set @ 35.lbs.Any thoughts on the air type bubbles.Thanks in advance Gary.

Gary,

I'm not sure of your mix ratio in the first sentence above, but it sounds like you mixed it 2:1:1 or 2:1:3 if I read that correctly. I tend to shoot it 4:1:1 for the 2021 Concept and will sometimes add more reducer to get it to flow on the last coat. One thing with urethanes, and you will notice this on your hood, is that they tend to build up right at the edge of a panel line or the edge of the piece, if it's separate from the model if you spray too many coats. This can be knocked down when you sand it. Or, if you spray light coats, and stop spraying when you have an "orange peel" looking finish, it will level out and as you build coats, it won't do this. It is very hard to take my own advice when I spray because I'm so impatient and want it to look smooth out of the gun, but if you do this, you will see an improvement. There have been occasions where I have followed that advice and the difference is amazing. It's the waiting that kills me!!!

I wait 10 minutes (set a timer, it's easier) for flash before the next coat and I stop at the orange peel look. When I do this, it always seems to work better.

I also don't spray much over 20-25 when using my airbrush for the stuff and my full size guns I spray at about the same at the tip (I have a gauge on them).

As far as your imperfections, are they affecting the silver or just the clear? You can have particles in the Hardener, that are clear in nature, but cause the effect you see. Did you strain the mix after you mixed it and before you shot it? Was your airbrush thoroughly cleaned (read: disassembled) before your clear coat? If you can only see them at the angle, and it did not affect the silver (or base coat, but silver in this case), then it's in the clear and probably a small hair or something to that effect. You will be able to sand this out and polish it as if it were not there.

A good rule of thumb to protect your investment in the PPG stuff or any line, is to store them in either zip lock bags or some air tight container to prolong their life. Also, with the gallon of clear that I have, I put a fresh piece of saran wrap under the lid each time I use it. It seals better that way and I do this for all of my QT containers and bottles too. I thoroughly clean the lip and the lid and then use saran wrap for the final protection. I also store them in a cool dry place and this drives my wife nuts. They are in the bottom of my food closet in the kitchen. But they are in a air tight container.

Hope this helps.

Ask Bob Downie about the dehydrator thing since he has the knowledge on that. I don't think that the dehydrator should have caused it.....it would be all over the model if it was a dehydrator issue.....that's my guess.

David

[Guest old man]

ok guy's i see great paint job's but how do you prep out the body what primer do you use or a primer sealer to keep the paint from atacking the plastic

[Chas SCR]

For prepping the body I think we all have are little ways of doing it also.. I normaly soke my bodys in CSC for 2 weeks and then I sand it down and do the body work on it. After that I was shooting it with Touch one Primer from Auto Zone, The Pontiac and the 57 Chevy was done in Du Pont Water base primer. After doing the primer, for example the 57 I shot it with bright white as a sealer or under coat. I do wet sand between coats of primer (normaly 3 coats) and then also 3 coats of under coats.

Now this is just what I found is easy for me.

[Steve Keck]

how do you prep out the body what primer do you use or a primer sealer to keep the paint from atacking the plastic

BJ,

Check out Mark Taylor's excellent tutorial on body prep here: http://www.modelcarsmag.com/forums/index.php?showtopic=30842

As far as primer goes I use Tamiya's under paints formulated for styrene and Plasti-kote sandable primer under automotive type paints.

Steve

[Karmodeler2]

ok guy's i see great paint job's but how do you prep out the body what primer do you use or a primer sealer to keep the paint from atacking the plastic

I either use Tamiya white primer or the Plasticote white primer (I think it's T-235...I know Car Quest carries it). I am a firm believer in white primer under every color coat when I use primer. Sometimes I choose not to use primer, but only when it's a model paint or something docile that won't attack the plastic. The Audi R8 I'm doing now has no primer, it's just Tamiya base and clear. If you use an automotive primer carefully, and put on light coats to build up the primer, it should prevent the bases and clears from attacking the plastic. Go to McDonald's and get some free spoons and try those first to see if there is a compatibility issue or not. Most automotive primers will protect the plastic. I have had some of the HOK bases attack the plastic, but I did not prime them first (my mistake).

I sand the body entirely first with 600 to remove any blemishes and unevenness in the panels. You would be amazed at how the panels on a model "rise" up at the edges. Go get a new body out of a kit and hold it up to the light and look down the side of the car....it looks like an accordion. That's the first step I do to get the body prepped. I also use a pin vise with a needle chucked up in it to deepen all the panel lines on the car. In fact, I do this first, then the sanding, so I don't sand away any body lines. I go so deep with the pin vise that if you look on the inside of the body, you can see the white line forming on the plastic on the inside of the model. It gives the panels depth.

If I prime, I then will prime it, and after about an hour or so, I will wet sand it with 800 to smooth out any imperfections, then I will wash the body thoroughly with soap and water, rinse thoroughly and then let air dry for an hour or so to make sure the water in the crevices is gone. I am wearing gloves at this point to keep from putting any oils from my skin onto the primer. To ensure you have a body that is dry, you can use your double action airbrush to just blow air in tight spots to make sure you are "water free". I then shoot my base and with in 10 minutes or so, if no taping or two tone is required, I shoot the clear. I try to get a chemical and a mechanical bond by doing this. If your base has dried, and you have not used an adhesion promoter, you are really only getting a good mechanical bond at best. A chemical bond is one where the chemicals, still being in a wet state (meaning, they are not cured and dry) will bond with each other. An adhesion promoter will do just that. It allows the base to be active for several days to accept the clear coat and bond chemically and mechanically to each other.

This is primarily used in the 1:1 world, but I have had the PPG clear not want to stick to some of the Tamiya bases after I have done a two tone or something, and now I add the adhesion promoter to the Tamiya base to keep it active longer. You should not have a problem with model paints when used exclusively.

hope this helps.

David

[Guest old man]

i have a buddy that has a body shop & they buy pint's to see if that is the color that the customer want's so he said i could have the paint's & reducer & clear coat so i will have a lot of color's to choose from i have a passach air brush that i will use for this

THANK'S FOR ALL THE HELP BJ

Edited August 27, 2010 by old man

[ScrappyJ]

But, the glowing accolades? I thought the primaries were over. Is David running for office?LOL!

Steve

LOL, Steve! The primaries are over, but figured I'd get a jump on the mid-term, general elections! See...folks don't know that I'm Dave's campaign manager. And what he doesn't know is that I suck at politics (he and I sit on opposite sides of the aisle: who says there can't be bi-partisan cooperation? ).

[ScrappyJ]

Dave- I may have missed it, but just in case, the one thing that helps tremendously with the preping of the body, particularly on the primer, is adding a little soap into some type of bowl or plastic container (preferably Dawn dish detergent) and also soaking your sandpaper in there for 30+/- minutes prior to wet-sanding. Dave taught me this trick and it does help prevent the build-up on the sandpaper, particularly with the finer grits 600+.

Edited August 28, 2010 by ScrappyJ

[Karmodeler2]

Thanks Dirk for the reminder. I got so focused on talking about primer that I forgot the most import part....sanding. Yes, you want to mix up some water and Dawn, and I even put some directly on the model sometimes. It will keep your paper from gunking up with primer or paint or clear. Thanks Dirk for mentioning this.

David

[slapshot]

Thanks David for your expertise & responding. Yes to all of your suggestions except the straining part. I did not run the final mix through a strainer. I take as many precautions that I can think of. I clean the airbrush with lacquers lay down plastic on the floor ,vacuum the floors, vacuum all areas of my spray booth & sprites water on all surfaces to help eliminate the possibles of dust etc.I will use the 4-1-3 next time as well. Thanks for taking the time to respond ,Gary

[Karmodeler2]

Thanks David for your expertise & responding. Yes to all of your suggestions except the straining part. I did not run the final mix through a strainer. I take as many precautions that I can think of. I clean the airbrush with lacquers lay down plastic on the floor ,vacuum the floors, vacuum all areas of my spray booth & sprites water on all surfaces to help eliminate the possibles of dust etc.I will use the 4-1-3 next time as well. Thanks for taking the time to respond ,Gary

Not a problem Gary.

I was just trying to think of all the "gremlins" that seem to come out of the wood work when you paint. I use the cone shaped filters you get at the paint jobber (the Dupont store or the PPG store or where ever you get your paint). If I really want to strain it and I'm worried about imperfections, I use a mesh that I get from Small Parts. They have them down to 1 micron which is really really small and will filter out every piece of trash known, and unknown, to man!!!

Also, with vacuuming the area, you might want to wait 45 minutes or so after vacuuming, if the motor of your vacuum is in, or near your booth. They tend to kick out a lot of dust, and stir a lot up when you use them. Unless it's one of those Herpa kind, it probably is doing more harm than good. Might want to get a longer hose and put the motor in the next room.

David

http://www.smallparts.com/s/16310161?ref_=sp_sc_1_2_lf&searchSize=20&searchNodeID=16414371&searchKeywords=mesh+screen&refinementHistory=subjectbin%2Cbrandtextbin%2Cenc-merchantbin%2Cavailability%2Creview-rating%2Cdate%2Cis_prime&searchBinNameList=subjectbin%2Cbrandtextbin%2Cenc-merchantbin%2Cavailability%2Creview-rating%2Cdate%2Cis_prime&searchRank=relevancerank

[slapshot]

Thanks for the link. I will order soon. I do have a up wright type vacuum(Dyson)that I vacuum the floor first & take it back into the house before my wife finds out that I have been using one of her prized toys. I then spritz the floor & Lay painter's plastic drop cloth over the floor etc. etc. I'm convinced that the imperfections are in the urethane clear mix,or at least till next time when Murphy raises his head & creates more confusion. I'm so annual I will take a lint tape roller & use it as the last step before I shoot the paint.

Edited August 30, 2010 by slapshot

[Karmodeler2]

Sounds like you are doing everything you could do to cut down on the gremlins. I think straining is the only thing that might take out the last gremlin roaming around. And I'm sure it will sand out of the clear....I do it all the time and it never shows when I'm done...I think you will be okay.

David

and your room looks really nice. Most of us would kill for a place like that!!!!

David

[Steve Keck]

The only thing I can add is that I prepare for gremlins. I have at the ready a new #11, a pair of fine tweezers, a pair of high powered reading glasses and a strong light.

If you see a fiber, or a spec of trash, sitting in the clear while its wet you can pull it out. Be careful not to disturb the color coat underneath. If need be, hit the spot with one more pass with the airbrush and it should level out with the rest of the clear.

[Karmodeler2]

Hey Steve,

you just reminded me. I had a guy give me a very small, delicate tool that looks like a small yellow plastic handle with a tapered piece of metal sticking out of it. It is very small (no longer than the distance between 2 joint lines on the inside of one of your fingers....unless you're Andre the Giant) and the tapered metal, when you look under the magnifier, is actually like a rasp, with little fingers sticking out from it. He says it is used in ceramics to remove small hairs and particles from the piece before firing and that he uses it to grab small hairs and stuff out of the paint when it's wet. Looking at it , it looks smooth, but pull it through two fingers with a light grasp and you can feel the roughness of the metal.

I have not used it yet, but it looks like it would be the cat's meow when it comes to removing hair from wet paint. I always end up hitting the model with tweezers and knocking a dent in the fresh paint and have to start all over. I will use this and let you know how it works. Maybe you could do some research and find out what it is.

David

[Steve Keck]

Hey Steve,

you just reminded me. I had a guy give me a very small, delicate tool that looks like a small yellow plastic handle with a tapered piece of metal sticking out of it. It is very small (no longer than the distance between 2 joint lines on the inside of one of your fingers....unless you're Andre the Giant) and the tapered metal, when you look under the magnifier, is actually like a rasp, with little fingers sticking out from it. He says it is used in ceramics to remove small hairs and particles from the piece before firing and that he uses it to grab small hairs and stuff out of the paint when it's wet. Looking at it , it looks smooth, but pull it through two fingers with a light grasp and you can feel the roughness of the metal.

I have not used it yet, but it looks like it would be the cat's meow when it comes to removing hair from wet paint. I always end up hitting the model with tweezers and knocking a dent in the fresh paint and have to start all over. I will use this and let you know how it works. Maybe you could do some research and find out what it is.

David

Sure, let me google "very small, delicate tool that looks like a small yellow plastic handle with a tapered piece of metal sticking out of it.... it would be the cat's meow" and see what pops up!

[Karmodeler2]

Sure, let me google "very small, delicate tool that looks like a small yellow plastic handle with a tapered piece of metal sticking out of it.... it would be the cat's meow" and see what pops up!

well.......what did it say?

[Karmodeler2]

Okay,

I think I found something similar. While this is bigger than the one I have (sounds personal to me), you can still see the little grooves cut into the surface.

David

http://www.axner.com/kemper-k31-zig-zag-saw.aspx