Ok I've been busy working on models and have built a few and am doing good. I can now paint with paintbrushes and see no brush marks in paint. So now I'm wondering is it better to paint every part on the tree before assembly or after everything is together. another question is, while I've got thick mud down, how do I simulate dust with a paint brush, drybrushing was a thought but hate to try it and mess a nice paint job up. Also I've been looking into battle damage, how do you simulate banged up fenders without breaking parts and how do you simulate damage from an ap round. I know it's alot but these are the questions I have after a few builds i completed

In most cases,it's better to assemble then paint.But there are exceptions.Some parts such as small add ons,acessaries or tools can be painted on the tree.

Whatever works for you.

Dust can be simulated by mixing up an enamel or oil buff paint wth thinner 90-10 ratio then it could be applied over an acrylic clearcoat and adjusted to taste.
you can get premixed stuff.I use AK Interactive Dust Effects.

AP hits can be drilled or melted in.Just check real pictures to see what they supposed to look like and go from there.

Fenders can be heated up and bent or twisted into shape after they are thinned by a dremel tool.Again real pictures are helpful.Some buy after-market Metal fenders and work them into shape.

Hi, Jared! I'm going to try to help you with your dry-brushing- As you gain experience, you may find yourself wanting to invest in an airbrush and an air compressor- something to think about in the future. Investing in an airbrush and a compressor will expand your horizons like you've never thought before... Once you've mastered your airbrush, you'll be able to recreate dust-effects that are a lot more life-like in appearance.

IMO, dry-brushing is meant more to bring out the finer details that are molded on, or added to your vehicle. With dry-brushing, in trying to replicate dust, you'll find that your brush won't be getting into those "hard to reach" places, where dust seems to collect most, and defeating your purpose in dry-brushing altogether.

Don't get me wrong- I'm NOT trying to discourage you in your efforts. Many years ago, I started out just like you did. Try dry-brushing VERY LIGHTLY at first, on the raised details of your model, developing your "hand" at it. The "KEY" here is restraint.

DON'T start out with a very light color first; try blending or mixing your base color with a lighter color on an old paint palette or an old model kit box, first. Make sure your brush isn't loaded up heavily- I use an old rag to wipe excess paint of my brush by rapidly stroking the brush back and forth on the rag first, leaving THE BAREST MINIMUM of paint on the brush. When you dry-brush, your hand pressure should be VERY LIGHT, as if you were tickling your model instead of painting it.

The whole point of dry-brushing is to "fool the eye" into thinking that "simulated light" is actually bringing out the details and highlights of your subject.

You'll want to mix successively lighter colors of your base color, and dry-brush the lighter shades more gently as you go lighter. This is so that your lightest shade will capture only the VERY HIGHEST points of your details. You shouldn't need more than 3 separate applications of your successively lighter shades, making sure that each application is thoroughly dry before you go on to your next... SEAL the whole business with a good FLAT SPRAY, such as TESTORS 1960 "LUSTERLESS FLAT", available from any reputable Hobby Shop or on ebay..

Once you graduate to using "Weathering Chalk Powders", you'll find that your dry-brushing experience will also come into play, here. Hope this helps...