MS paint all the way. just zoom in x8 grab your line tool and go at it. you can actually make things look quite good with some patience.

For example, to make a metallic looking rod, you would draw a pale gray line, you would then draw a darker line the same length either side of the central line. You then draw 3 or 4 ever darker lines either side, and when you zoom out it looks like a metal rod.

Remember to always try and work in odd numbers. If you want to make circles that have an exact center you will need to work in odd numbers.