another orange peel question

[dlh]

This is my first model, trying to replicate a 320i I owned.  I primed with Testors white primer and sanded.  The paint is from Express Paints and is an automotive urethane with a clear coat from the same company. I saw the orange peel after the second color coat, but the directions said not to sand before clear coat.  The roof has more primer after I tried (and failed) to fill the sunroof.  The orange peel seems to be all on the color coat and not in the clear coat. The side view has less primer and less orange peel. I didn't sand the engine compartment at all that that seems to have no orange peel.  I shot it with a Paasche H @‌ 35 lb.  The paint was decanted from a spray can and was not thinned.  From what I've read, orange peel forms when the paint dries before it has had time to level out. The spoon wasn't primed at all, just lightly sanded before painting, and clear coating and has no orange peel.

This body is a "throw away" after I screwed up the panel lines and the hood.  I have three more.

Is it possible that multiple coats of primer are drying the color coat too fast?  I'm going to spray more spoons with different coats of primer and possibly lowering the pressure.  Any thoughts?

What would happen if I sprayed the body without primer?

Thanks

Dave

Edited March 14, 2017 by dlh
Added question

[Impalow]

My guess is.. and only my guess...    looks like the base coat lightly attacked the primer or the plastic... or you put it on a tad too dry...     For what its worth, you usually can sand a metallic basecoat to save this sort of issue...   you will just have to put on another color coat before you clear.....  

Edited March 14, 2017 by Impalow

[Impalow]

another thought.... Ive had basecoat and nail polish spray like that when its too thick...   goes on dry and pebbly...  thinking that could be the issue.    With base you only want to put enough on to get an even color, so if the first coat went on a bit pebbly..and then you loaded up the second coat to try and hide it... its possible it got a bit thick, and the solvents attacked the primer?   Its hard for me not being there... and not having used that particular paint... but those are 2 scenarios I've ran into before.

[Ace-Garageguy]

You have two issues besides the possibility that Eric mentioned, and I'll expand on his thoughts.

One, if you look CLOSELY at the metallic, you'll see it's grainy and not smoothly distributed like what's on your spoon. This appearance is the result of excessive film build as well as dry spray not self-leveling. As Eric rightly points out you CAN sand this flat prior to clear, as long as you shoot an additional coat of metallic to even out the metallic effect (which will be disturbed unevenly by sanding).

Two, you also have definite orange peel in the clear itself. This is evident in the broken reflections of the light source. Again, not a wet enough application to allow self-leveling of the material.

The problems with shooting spoons, as I've tried to explain multiple times, are also twofold. The plastic that spoons are made of is not necessarily the same as the plastic that models are made of, and shooting spoons DOES NOT help you to develop a good spray technique for much larger model car bodies.

Practicing your spray technique on old junk bodies is ideal, if you strip them in between practice sessions...but priming and practicing your spray technique on small plastic soda bottles is much simpler. They're about the same size as a model body, allow you to get the feel for getting good overlapped coverage (without too much buildup) as you turn the things, and are entirely disposable.

One more thought...automotive urethane clears are designed to provide much greater film thickness than is required for model work. This can be compensated for to some degree by over-thinning after the hardener is thoroughly mixed in. The film thickness of these products tends to fill details, and if shot wet enough to flow out well, as mixed (without additional reducer) often produces a finish that, though very slick and glossy, also has the appearance that the model has been dipped in syrup due the to rounding of panel edges and filling of panel lines.

Edited March 14, 2017 by Ace-Garageguy

[dlh]

You have two issues besides the possibility that Eric mentioned, and I'll expand on his thoughts.

One, if you look CLOSELY at the metallic, you'll see it's grainy and not smoothly distributed like what's on your spoon. This appearance is the result of excessive film build as well as dry spray not self-leveling. As Eric rightly points out you CAN sand this flat prior to clear, as long as you shoot an additional coat of metallic to even out the metallic effect (which will be disturbed unevenly by sanding).

Two, you also have definite orange peel in the clear itself. This is evident in the broken reflections of the light source. Again, not a wet enough application to allow self-leveling of the material.

The problems with shooting spoons, as I've tried to explain multiple times, are also twofold. The plastic that spoons are made of is not necessarily the same as the plastic that models are made of, and shooting spoons DOES NOT help you to develop a good spray technique for much larger model car bodies.

Practicing your spray technique on old junk bodies is ideal, if you strip them in between practice sessions...but priming and practicing your spray technique on small plastic soda bottles is much simpler. They're about the same size as a model body, allow you to get the feel for getting good overlapped coverage (without too much buildup) as you turn the things, and are entirely disposable.

One more thought...automotive urethane clears are designed to provide much greater film thickness than is required for model work. This can be compensated for to some degree by over-thinning after the hardener is thoroughly mixed in. The film thickness of these products tends to fill details, and if shot wet enough to flow out well, as mixed (without additional reducer) often produces a finish that, though very slick and glossy, also has the appearance that the model has been dipped in syrup due the to rounding of panel edges and filling of panel lines.

Well, much to think about.  Thanks for the detailed response. I'll practice on some soda bottles before shooting another body.

Would shooting at lower pressure be a good place to start?  Maybe this exact color matching requiring urethane is beyond my beginner's technique.

Thanks again for the explanation.

Dave

[MrObsessive]

Looking at your first pic, I see a bit of ghosting on the roof from where you filled it in. I'm a BIG fan of putting some kind of barrier coat on plastic especially where bodywork is involved. Paints can react differently to variations in putty and plastic, and it never hurts to give it that bit of protection on the plastic, particularly when you're using a rather hot paint such as a urethane.

As Bill mentioned, plastic spoons are made of a different type of plastic than what's in a plastic kit. They're styrene, but a much more durable styrene than what kits are molded in today. After all, we gotta try and eat with the things so they gotta be kinda tough no??

As far as a barrier, I'm a believer in this..................

I've been using this for awhile, and haven't had an issue with it. You'll need an airbrush (an old one preferably), and alcohol will thin it and clean out the airbrush when you're through. 

Hope this helps!

Edited March 14, 2017 by MrObsessive

[Miatatom]

Would shooting at lower pressure be a good place to start?

Dave

The only comment I would add is that 35 psi sounds too high. I use the #5 tip with my Paasche H and shoot at 22 psi. What tip are you using?

[dlh]

The only comment I would add is that 35 psi sounds too high. I use the #5 tip with my Paasche H and shoot at 22 psi. What tip are you using?

#3 tip

[crowe-t]

I recently attempted to use Urethane 2K clear on a model body.  I sprayed it over a synthetic lacquer color.  I found that the urethane 2K clear seems to need to be sprayed on thick to get it to level out and it can attack decals if applying it over them.  I wasn't happy with the results at all.  It flowed too easily and filled in details and still had some orange peel unless I sprayed it on thick.  

I also have another project that I'll be using PPG Omni Acrylic Urethane for the base color coat.  This particular paint is NOT activator(hardner) based and only requires thinner(reducer).  I wanted a specific factory metallic color so I had some mixed at a local automotive paint supplier.  I tested spraying some and it sprays beautifully and can be reduced down as thin as I need it.  I sprayed Testors MM Ultra Gloss Clearcoat on top and it's compatible.  I like that the Testors MM Ultra Gloss Clearcoat reduces down and goes on thinner than the urethane 2K clear.

For a model I feel that urethane 2K is a bit over kill.  It tends to look thick like syrup.  This is just my opinion.  I think the hobby clear lacquers are more in scale than urethane clears for model cars.    

Tamiya Fine Surface Primer is a nice thin primer that goes on very smooth.  This might help.

 

 

Edited March 15, 2017 by crowe-t

[Impalow]

 

For a model I feel that urethane 2K is a bit over kill.  It tends to look thick like syrup.  This is just my opinion.  I think the hobby clear lacquers are more in scale than urethane clears for model cars.   

I agree and disagree with this.... Not all of the 2k products are equal.    I have noticed the premium clears are thicker and have a higher build than most, but the value line clears are thinner and seem to work better for model purposes.  

The clear I use is a USC product that is 35.00 for a quart "kit", it sprays great and doesn't have that syrup look.    My paint guy always tries to up-sell me to the premium clears touting "higher build, and better UV protection"   neither are really positives for what we are doing with them.  

Personally I prefer the basecoat/clear coat process for painting models...   It allows me to separate my stress into two compartments, color and shiny.   Get the color on even and smooth,   then get the shiny on even and smooth...   Two chances to succeed (or goof up) but more control throughout.   Plus the drying/curing time, buff-ability and predictability of the urethane clears are huge advantage in my eyes.

I have had the issue with the decals on my recent project.... and it was a major bummer...   I tend to think I can spray urethane clear over everything without any issues... and I have for the most part... its pretty mild... but decals have caused me all sorts of headaches.  I had some spots where it actually ate/dissolved the decals, other spots where air bubbles trapped under the decals released... it was a pain.

#3 tip

 

Back to this.... when i had this problem in the past... My paint was too thick and I was using too small of a airbrush... I'm guessing that's probably your issue.     Not sure what type of air source you are using... but....  I spray all of my overall color paint jobs and my clear with this gun:

http://www.harborfreight.com/adjustable-detail-spray-gun-92126.html

It lays down most paint nice, has a nice fine spray pattern... and with a coupon you can usually get it for 12.00ish    We tend to use them for a year and throw them away, and get another.  If you do get one, make sure you tighten all of the packing before the first use, I have had them loose from the factory and my paint just runs all over my hand... haha. 

Edited March 15, 2017 by Impalow

[crowe-t]

 

Back to this.... when i had this problem in the past... My paint was too thick and I was using too small of a airbrush... I'm guessing that's probably your issue.     Not sure what type of air source you are using... but....  I spray all of my overall color paint jobs and my clear with this gun:

http://www.harborfreight.com/adjustable-detail-spray-gun-92126.html

It lays down most paint nice, has a nice fine spray pattern... and with a coupon you can usually get it for 12.00ish    We tend to use them for a year and throw them away, and get another.  If you do get one, make sure you tighten all of the packing before the first use, I have had them loose from the factory and my paint just runs all over my hand... haha. 

I'd like to get one of those spray guns but my compressor is a hobby compressor and only puts out 1.2 CFM@open flow.  I have a good compressor, Iwata Power Jet Pro, but it's most likely not enough for this spray gun in the link.

Edited March 15, 2017 by crowe-t

[dlh]

You have two issues besides the possibility that Eric mentioned, and I'll expand on his thoughts.

One, if you look CLOSELY at the metallic, you'll see it's grainy and not smoothly distributed like what's on your spoon. This appearance is the result of excessive film build as well as dry spray not self-leveling. As Eric rightly points out you CAN sand this flat prior to clear, as long as you shoot an additional coat of metallic to even out the metallic effect (which will be disturbed unevenly by sanding).

Two, you also have definite orange peel in the clear itself. This is evident in the broken reflections of the light source. Again, not a wet enough application to allow self-leveling of the material.

The problems with shooting spoons, as I've tried to explain multiple times, are also twofold. The plastic that spoons are made of is not necessarily the same as the plastic that models are made of, and shooting spoons DOES NOT help you to develop a good spray technique for much larger model car bodies.

Practicing your spray technique on old junk bodies is ideal, if you strip them in between practice sessions...but priming and practicing your spray technique on small plastic soda bottles is much simpler. They're about the same size as a model body, allow you to get the feel for getting good overlapped coverage (without too much buildup) as you turn the things, and are entirely disposable.

One more thought...automotive urethane clears are designed to provide much greater film thickness than is required for model work. This can be compensated for to some degree by over-thinning after the hardener is thoroughly mixed in. The film thickness of these products tends to fill details, and if shot wet enough to flow out well, as mixed (without additional reducer) often produces a finish that, though very slick and glossy, also has the appearance that the model has been dipped in syrup due the to rounding of panel edges and filling of panel lines.

So much help here. Great forum.

I tried yesterday spraying soda bottles and it's starting to look better.  I used an Iwata Eclipse and lowered the pressure. I think, as you said, that the base color was attacking the primer.  I tried samples with and without primer.  The samples without primer looked better.  The paint I'm using is not a 2K.  The more I look at the first body, the less I like it.  The panel lines are too deep. The build up is too high.  Like you said, looks like it's dipped in syrup.  I'm going to try one more body without primer and if it doesn't work out, I'll switch to regular enamel and not worry about exact color match.  The primer I used was Testors enamel.  Maybe if I had bought the primer from Express Paint, I'd see better results, but the paint and clear was expensive enough.

Still, this is my first model in 40 years, so I'm a beginner with lots to learn.

Thanks again,

Dave

[MrObsessive]

If at all possible, stay away from the Testors Enamels!

To me they're only compatible just with their paints and certainly not with the type of paints you're using. A lot of folks here use Duplicolor, and I personally like Plastikote Sandable Primer. Some may swear by Testors Enamels, but in past years I've had trouble with them as IMO, they're just not as compatible with other paints as I'd like. 

[High octane]

I've been using Tamiya primers these last few years and like it a lot. One way to avoid "orange peel" is to spray closer to the body and move the can/brush faster across the body, therefore not giving the paint a chance to dry before reaching the body.

[dlh]

If at all possible, stay away from the Testors Enamels!

To me they're only compatible just with their paints and certainly not with the type of paints you're using. A lot of folks here use Duplicolor, and I personally like Plastikote Sandable Primer. Some may swear by Testors Enamels, but in past years I've had trouble with them as IMO, they're just not as compatible with other paints as I'd like. 

Always appreciate advice while I'm learning.  I was a little suspicious of the Testers Primer as soon as I started spraying the urethane color coat. I'll go with Tamiya paint on my next model.  I've used Tamiya paints on the inside of lexan RC car bodies with great results.  That's a different animal though.

I have two rattle cans of Tamiya fine surface primer.  Plan to decant some of that.  Do you think Duplicolor and Plastikote are better than Tamiya primer?

Thanks

[MrObsessive]

 Do you think Duplicolor and Plastikote are better than Tamiya primer?

Thanks

That's a loaded question as everyone has their preferences. To me, Tamiya primer is OK, but for the cost IMO it's too expensive considering you may be able to do only two or three cars tops. The other brands come in much bigger quantities for the price, and since I've had no trouble with Plastikote particularly, I like to stick with what works.

Plastikote in my experience has been more user friendly, but it can be hard to find locally. Duplicolor I've seen tends to be a bit too much on the "hot" side, thus as I mentioned in another post---------putting a barrier on the plastic first can ward off any surprises no matter which primer one wants to use........ESPECIALLY when there's bodywork involved.

I don't know if you've seen it........but here's my '59 Chevy that I painted using the method I described. LOTS of bodywork went into this as there was a total roof swap involved as well as opening doors and trunk. The build pics can be seen here.......

As you'll see in the pics leading up to painting, a barrier coat was put on the body before primer, then I used several coats of Plastikote Sandable gray as the undercoat. The color coat is automotive Dupont Roman Red which a local paint jobber mixed for me. I let the body thoroughly dry for about a week or so, then the paint was rubbed out with Detail Master polishing cloths, and then polished with Meguiar's Car Cleaner Wax with a chamois cloth.

[Impalow]

That's a loaded question as everyone has their preferences. To me, Tamiya primer is OK, but for the cost IMO it's too expensive considering you may be able to do only two or three cars tops. The other brands come in much bigger quantities for the price, and since I've had no trouble with Plastikote particularly, I like to stick with what works.

Plastikote in my experience has been more user friendly, but it can be hard to find locally. Duplicolor I've seen tends to be a bit too much on the "hot" side, thus as I mentioned in another post---------putting a barrier on the plastic first can ward off any surprises no matter which primer one wants to use........ESPECIALLY when there's bodywork involved.

I don't know if you've seen it........but here's my '59 Chevy that I painted using the method I described. LOTS of bodywork went into this as there was a total roof swap involved as well as opening doors and trunk. The build pics can be seen here.....As you'll see in the pics leading up to painting, a barrier coat was put on the body before primer, then I used several coats of Plastikote Sandable gray as the undercoat. The color coat is automotive Dupont Roman Red which a local paint jobber mixed for me. I let the body thoroughly dry for about a week or so, then the paint was rubbed out with Detail Master polishing cloths, and then polished with Meguiar's Car Cleaner Wax with a chamois cloth.

Had the pleasure of seeing that in person last year in new jersey... amazing work!  and great advice!

I have two rattle cans of Tamiya fine surface primer.  Plan to decant some of that.  Do you think Duplicolor and Plastikote are better than Tamiya primer?

Thanks

personally, and others may disagree...  I just spray the tamiya primer (or duplicolor/ plasticoat) straight out of the can...  no real need to decant it, unless you are priming really finite detail work.   You are going to sand before paint anyway, so a little texture from the can spray doesn't hurt.   Plus the tamiya primer fine primer is super fine and sprays pretty decent.   

Edited March 16, 2017 by Impalow

[Brett Barrow]

Always appreciate advice while I'm learning.  I was a little suspicious of the Testers Primer as soon as I started spraying the urethane color coat. I'll go with Tamiya paint on my next model.  I've used Tamiya paints on the inside of lexan RC car bodies with great results.  That's a different animal though.

I have two rattle cans of Tamiya fine surface primer.  Plan to decant some of that.  Do you think Duplicolor and Plastikote are better than Tamiya primer?

Thanks

Different animals, if you ask me.  Tamiya's nice and thin, works great for preserving sharp detail on box-stock builds. It's made for models.   Duplicolor & Plastikote are high-build filler/primers made for real cars and work great if you do lots of bodywork like on a custom and have a lot of putty and sanding scratches and blemishes to fill in.  Both have their place.   I agree with Impalow, don't bother decanting Tamiya primer, the difference (if there even is one) isn't worth the hassle.  

[High octane]

Had the please of seeing that in person last year in new jersey... amazing work!  and great advice!

personally, and others may disagree...  I just spray the tamiya primer (or duplicolor/ plasticoat) straight out of the can...  no real need to decant it, unless you are priming really finite detail work.   You are going to sand before paint anyway, so a little texture from the can spray doesn't hurt.   Plus the tamiya primer fine primer is super fine and sprays pretty decent.   

I hafta agree with you Eric as I decant Tamiya primers and paint right from the can to the body, and it seems to work out very well.