My Next Questions On Airbrushing Acrylics On IHC Steam Loco

Model Railroader General Discussion (Model Railroader)
1

Rather than add to a prior thread, to minimize reading, I’ll add my newest questions and welcome any help. The loco is a 4-6-2 that I stripped, primed with Modelflex gray primer, and base coated (2 weeks ago) with Model Master 2/3 grimy black, 1/3 engine black. Up until then, no issue.

Yesterday I airbrushed a Model Master gloss coat in prep for adding decals. Not so good.

a) The loco appears a bit non-glossy, almost like dusty, but not like the underlying paint had rippled. Perhaps hitting the loco too dry? I was trying to avoid getting it too wet or thick to avoid drips. Realize I am still learning to use my Paasche VL. I added about 10% Paint Easy thinner. Sprayed at about 27 psi.

b) I sprayed another coat after only about 20 minutes, and ended up with the effect described. It’s not awful, so I wonder if I can either add another wetter, smoother coat or just add the decals and then add another (properly done) gloss coat. I plan to finish with a coat of semi-gloss.

c) The tender, also getting two coats with minimal drying time, looked worse. It appeared some paint had crinkled just slightly on the sides and rear. I could not tell if the base coat crinkled or if the 1st gloss coat crinkled. Since I have the speaker already installed and the tender is not satisfactory, I hand stripped the sides and ends today with denatured alcohol for re-priming, etc.

I think the relevant questions are obvious; i.e., appropriate psi, how to add a coat (how wet), time between coats, etc. Another obvious issue is that I need to practice on a couple of old cabooses in the queue, but I wanted to know how to approach this before practicing on those. I’ve looked at many an old thread but not found quite the insight I need to move forward.

2

It almost does sound like a couple of different issues, one possible being that it was hitting too dry.

Also, was it thoroughly mixed, including thinner? It could also be that it wasn’t mixed quite enough…

My main question -

How did the clear coat appear when being sprayed on? Was it hitting “ruff”, or was it smooth going on?

27psi is a high pressure, especially for gloss clear.

I will do that high when weathering with flat colors, but only because of the effect it gives, of a ruff texture.

For gloss, I normally spray closer to 21-22psi, and have less issues that way.

Your paint was only thinned by 10%? That’s too thick still.

I thin my clear gloss between 25-33% (between 1/4-1/3) compared to standard paint. (Of course, I have Modelflex for clear gloss, which is thinner already than ModelMaster paint, so maybe thin by as much as half?)

Yes, I do a couple (2-3, depending) of coats, but it lays nice and smooth that way.

For clear coats, you want to aim for between 1% and 2% milk consistency. (My clear gloss goes closer to 1% side. Flat closer to 2% side. Color consistently 2% side.)

3

Thanks, Rick!

I think it was hitting too dry. Did not seem to want to make a wet looking coat at all. It looks a bit like dusty or like super fine sandpaper in places.

I will address that. The Model Master is not that thick, but I just put Paint Easy that would fit in the new bottle as a 1st try.

So, I can do a coat on the loco, then the tender, then (less than 5 minutes later each) another coat. Or simply wait an minute or so and add the 2nd coat becuse the paint starts drying so fast. The first coat does not need to be “dry” to much of an extent? Said another way, the 2nd coat can go on pretty soon, as long as the slightly wet (little dried) 1st coat and the added 2nd coat don’t create enough wet layer to start a run? How long to wait?

I think there is even more to my list of interrelated errors. Per above, too thick paint, too high air pressure. Perhaps add to that pulling the trigger back fully, rather than moderately. So with the high pressure and full trigger, I was spraying pretty far away due to fear of runs, so it was probably hitting pretty dry.

I will strip those old trial cabooses today and prime them and the tender. Then paint, then gloss the cabooses. If I get those done better, I will repaint and gloss (for decals) the tender.

Thanks very much.

4

Hi Paul,

Excellent responses from Ricky W. [Y][8D] I own 2 Paasche’ VL’s and have been very happy with them. Keep them clean and they’ll give you YEARS of good service!

Before you prime those cabooses…i would like to respectfully add that, in reading your opening post, it sounds like you’re not testing your mixes.

When I started airbrushing way back in the 80’s, I tended to be impatient and excited to start “painting away”. After a couple of rough jobs, I disciplined myself to slow down, test my mixes and enjoy the process.

It’s ALWAYS a good step to test your mixes first on scrap materials. You will instantly see if you need to adjust your air pressure, work distance, stroke speed, or paint mixing. It seems like a hassle, but for a smooth slick job, imho, it pays off.

I’ve suggested the following before. If scrap rolling stock shells are in short supply or too expensive, look at two potential “free” sources:

1. Build up a collection of of peanut can, coffee can, or tea can plastic lids. Your friends, coworkers, and relatives likely already have them. Just request that they save them for you.

2. Compact Discs (and CD cases). Public schools are a great “free source” as teachers keep them for years and forget to toss them. You’d be surprised at how many “Windows 95” formatted CD’s are still floating around out there! If you have kids, nieces, nephews, etc, in school they can ask their teachers for them. If not, just call your local public school and ask to speak with the media specialst (Librarian). A few years back, a teacher thanked me for cleaning out her cabinet drawer of 20+ year old obsolete CD’s.

I keep them in a bag near my work table. Here are some on display, including a test sample that I applied gray and clear coat on to.

Cost o

5

Thanks for all the good advice.

I have made the important decision to proceed sensibly, at least in this case.

I will first do some practice to learn how to airbrush these items. I am currently stripping the caboose bodies. I will do some practice runs (primer, paint, gloss coat, decal, final clear coat) to develop some reasonable technique. The cabooses will be (ModelFlex) UP armour yellow, which I think needs white primer, which I just ordered. I don’t want to use spray can primer as I think it will go on too thick. My practice will include engine/grimy black (Model Master) and yellow paint coats, with semi-gloss and flat clear final coats, respectively.

Oh, I need to get some cashew cans tomorrow for the lids to practice on! Not sure how many I need.[;)]

With a little confidence built, I will try the cabooses. Just old Roundhouse & BB cabooses to repaint in UP scheme. With any success there, I will address finishing the IHC Pacific.