If I use putty, I apply it using a wooden Q-tip that I've sanded down flat on one side. I just grab some putty out of the tube with this tool and go to town. (I've made several of these little jobs, all shaped differently.)
I don't worry too much about surrounding detail because 1) I usually build kits that have engraved lines which are much easier to restore than raised lines, and 2) I generally don't use much putty. It's a matter of controlling the application of the stuff onto the model. With practice and experience, you'll find that you use less and less with each successive project.
Anyhoo, nowadays I mostly use Mr.Surfacer made by Gunze Sangyo. This stuff is great for most seams and it's a liquid that can be applied much more precisely than putty. There's 500 (thick) and 1000 (thin). I use 500 almost exclusively and apply it with a brush in thin coats, building it up as needed.
When sanding nowadays, I use sanding sticks almost exclusively. Too bad, too, 'cuz I have more sandpaper than has been made!! I love sanding sticks, you can get 'em at drug stores, supermarkets, dollar stores, beauty shops; you name it! And they're CHEAP! (Depending where you get them, of course...) You can also get them through hobby retailers, but they'll be much more expensive.
Here's a tip for the sanding sticks. Even though it's co$tly, get yourself one of Squadron's tri-grit sticks. These are the ones with one side divided into two sanding/finishing grits and the other side being a smooth polisher/buffer.
Now, find some of the tri-grits at various stores that have grits which exactly match those of the Squadron stick. Some of the sticks you find in drug stores and such are a bit more coarse than the Squadron deal. These are useful as well, but you want the same grit as on the Squadron stick for finishing before painting. That's what I use exclusively and I get stellar results. Sandpaper is almost a thing of the past for me. However, experiment with different types of sanding materials, what works for me may not work for you.
Going back to Mr.Surfacer, some folks have used the 1000 as an overall primer, but I prefer to use actual paint. I dunno who carries it online, I get mine locally or at shows.
Speaking of primers, I use whatever flat black I have laying around the bench. I paint everything black before I apply color; but then, I'm weird. And speaking of paint...
Testors still makes enamels, and they also make acrylics. The health issue is a bunch of BS because neither of them are good for you, matter of fact acrylics are just as bad for you as enamels. (Especially if mixed with ginger ale!
)
It's just that the smell of acrylic fumes seem to be a bit less noxious to some. I use enamels because they've never let me down of their own accord in any way. I just find acrylics to be a pain in the you know what. (Water clean up my...)
My absolute fave line of paint is the Floquil/Aeromaster enamel line, but I probably shouldn't even mention those, (Too late!) they're out of production. If you're inclined to use enamels and see these paints anywhere, grab 'em! Great stuff!! Speaking of Floquil, I also use their Railroad lacquers now and again.
Okay, backtracking again. Going back to sanding and losing detail. If you do build a kit with raised lines, you can replace them with stretched sprue, as I believe was mentioned already. It ain't the easiest thing to do. My Dad once built a TBD Devastator which has the ribbed wings. He lost a buncha detail sanding the leading edges and replaced it all with sprue. Just goes to prove that he was a helluvalot more nutzo than I am!!!
If you build a kit with engraved lines and need to restore detail, there are many scribers available out there for purchase. You can also use certain dental picks and a real simple device; a sharp pin held in a pin-vise. I'm lucky in that my Dad brought home alotta "out of spec" stuff from work, including carbide scribers!!! (YAY!) When I use an actual scriber, invariably, that's what I use. But my absolute fave tool for engraving lines is a triangular jeweler's file or needle file. Take a look at
my pathetically meager website for an article on scribing lines with these little jobs.
Try as much as you can, be it different paints, techniques or whatever. Decide what's right for you. Take it one step at a time, as well. Whatever you're putting out now, you WILL get better. But it takes time, practice and alotta really bad screw-ups!!!
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