Hi Steve - thanks for the compliment
All of the panel line and rivet details were done with epoxy finishing resin thickened up with a little bit of microballoons, or thinned out with methyl hydrate (denatured alcohol I believe it is in America). The same easy sanding stuff that you use for glassing. Zap etc.
First I finish the entire plane and get it perfectly flat and glasssy smooth so that I can see the reflection of a dime in it with a handheld light. After that I lay out the panel lines with a sharpie, I study the original plane to see which are lap joints and which are butt joints. If you can't find details of the order that panels were installed at the factory, a good rule of thumb is that you can start at the bottom of the fuselage and work towards the top. (this is assuming that your plane was manufactured in a similar method to the P40) So let's say they put the first panel on the bottom and rivet it down. The next panel will overlap the edge of the first one. Then the third panel is going to overlap the edge of the second etc.. So to create this effect, I lay down tape on the outside of the panel edge (bottom) and brush on some finishing epoxy and microballoons along the edge and extending into the centre of the panel section. After it has setup, but is still a little green and you lift the tape, you will get a nice crisp edge to the panel. Then you blend it in towards the centre of the panel. I like the subtle look of individually finished panels. It's subtle but if I put two models down side by side the one with individually finished panels will make me drool, and the other one will end up in a swap meet lol.
Where you have a butt type joint (usually vertical where panels meet) you do the same thing blending towards the centre, but you butt your tape up to the edge of the last panel to simulate two panels meeting.
Yes, it does take some time. First I finish the entire plane to paint readiness, then I finish each panel separately again.
After the basic panels are on, I move on to fairings etc like around the tail and wing fillets. Here I mix the microballoons a little bit thicker and I apply it in the same fashion but heavier. Once those areas are all sanded to look like metal again, I apply rivets to the areas where they were visible on the original. On this plane this happens on the heavier fairing panels around the wing and tail fillets and some around access panels. I don't put alot of other flush rivet detail on the fuselage because you really can't make them out on the original plane unless you walk up and look for them, and this one is only 1/7th scale.
The rivets are made with the same epoxy and microballoon mix applied with the end of a wire so that you can scale the wire gauge to the rivet size. Just dip it in, and dab it on. Practice somewhere to get the consistency of the epoxy so that it won't sag or run after you apply it. Once they have dried, you just sand the tops down flat.
It's all about the layers I find. By the time you're done, you will have an intimate knowledge of each panel
Rivets aren't so bad - on the fuse anyway.
IMHO chart taped panel lines just don't do it for me anymore. Nothing against it, I just did that for too long.
Sorry for the wordiness.