I definitely agree with your points about contests, my friends @pikofix, @gblair and @johnb!
And, yes, modeling is an activity carried out for pleasure.
Csaba, your progress is very solid, really amazing!

George, @gblair most of the time works fine for me as well, especially on the instrument panels. I used to spray a thin layer of matt varnish to dampen the shine, but that´s all. I used to wor kin 1:72 scale, and actually these pre-painted parts look great. Sometimes tricky to match the color of other parts, that´s all. I think in this larger scale the parts will look better if I repaint them.

Not that much progress on this week, life happens, and suddenly it was Friday. I managed to cleanup a few leftover parts (undercarriage and wing struts), and adjust my building jig to fit the Po-2. I have quite a few things to take care of in the coming days, but I will reserve a quite morning to do the priming.

I also took a look in my paint stash. There are no records of the exact colors of the plane, so I have to make an educated guess. I have Vallejo´s 71.002 Medium Yellow (basically RAL1023 / FS33655 ). It is a pretty good match to the yellow used on the planes on that period. Maybe it needs a drop or two red to pull it into a bit more orange, "trainer yellow" color.
The red is more tricky, I don´t have too many red paints at home. I have a lovely Xtracolor SAS airline red/orange, never used. If you have ever seen a passenger plane from SAS, you know this color. It was used on the engines on the previous livery. I love that color, and I think it would fit quite well to the "trainer yellow" base. However, it is enamel, and I am not used to these paints anymore. I can´t remember the last model I painted with enamels. Must be 20+ years. or something like this.
I have Vallejo´s 71.084 Fire red (FS31350) and 71.003 Scarlet red (the new reference chart lists this as RLM23, but I have a very old bottle). The Fire red is dark, the Scarlet red is too light, it should be somewhere between the two. Maybe I will buy a new red, it is missing from my stash anyway.
I also have to take a look on the national colors, those are also well defined (the current standard colors of the Hungarian flag are Pantone "18-1660 TCX Tomato" for the red and "18-6320 TCX Fairway" for the green. The white between the two other colors is.. well, white. Of course real life does not follow the standard, and there are variations on the planes in real life. Most of the time the colors are a mid/deep red, and a mid/dark green, divided by the white.

I plan to do a quite standard yellow paint job, grey Mr. Surfacer as primer, patchy white layer as a base layer, and yellow on top. The patchy white layer will add some variation to the top layer. I plan to add more variation with the oil dot technique, but for that I have to buy a few more colors. My current, very limited oil paint range is for imitating oil leakages and making basic panel line washes.

1 attached image. Click to enlarge.

Good color preperation, Csaba @pikofix
How about the Vallejo 71.085 (Ferrari Red), this might get closer.

Spiros, @fiveten, I am not really obsessed with matching colors either. If the overall result looks fine, I am happy. Anyway we modelers apply all kind of pre/post shading, washes and other weird techniques. Those will change the color anyway.
John, @johnb good point with the Ferrari red, I think I will give it a try. Just preparing an order with a few other things as well.
George @gblair it is indeed a challenge to find proper colors, especially with less documented subjects. Luckily, I am also interested in drawing and watercolor painting (very-very-amateur's level), and I learned a lot from painting a few pictures and mixing colors.

The interior colors are easier - I will go for a steel gray. I have no idea whether the original interior color was changed when the plane was overhauled. The original color was most probably grey - but I am really not sure.

The next question, should I assembly the whole model before painting, or should I prepare and paint the upper wings separately? I am afraid that gluing painted parts will cause problems.

@pikofix

While constructing the Walrus, I was facing the same problem.

Usually I build single wing planes and that makes painting easier.

For the bi-plane I did painting first and glueing secondly, like mentioned by Spiros @fiveten.

Because of the applied camouflage I had no other option.

You do indeed have to take care of the paint while assambling the part.

A sad side-note - I will need a new compressor, probably soon. I have a 15 years old unit, and I noticed that it started to overheat. It also became noisy, and has problems with starting the compressor after loading the tank a few times. It is a shame, because the unit came with all kind of goodies, a 5 litres tank, water separator, pressure regulator, a massive compressor. Any recommendations out there? I would prefer something with a tank, but as I wrote earlier, I have limited space, so maybe it is time to switch to a more compact unit.

All parts look great under Mr Surfacer, my friend @pikofix!

@johnb, thanks, I will take a look on those as well. As I see those are all maintenance-free compressors, running without need of refilling or changing the lubricant. It is a great thing, just turn it on, and will run for many years. The popular Sparmax compressors are the same, and I am not sure whether the price tag really reflects better quality. They offer a similar unit to your Fengda for twice as much.
The drawback is that these maintenance-free compressors are loud. I live now in an apartment building, and I have time for airbrushing in the late evenings. I am not sure how my neighbors and family would react to a loud compressor. We plan to take a look on the market and move to a house in the near future, but that´s a very different story. 🙂

I have a low cost, but factory made silent compressor, similar to the Werther silent air compressors. Mine is in the storage room now, but found a photo online - the difference is the color, mine is fancy red. 🙂 It was very silent at the beginning, but became more and more loud. I think the problem is that I did not really spent time on maintenance, since the manufacturing company is now defunct, and the unit is not designed to be user serviceable. I can try to order a bottle of compressor oil, refill it by feel, and see if it helps. That would be a relatively cheap thing to try, and maybe it would keep it alive for a while.
A new silent compressor would be an expensive addition to the hobby budget... :/