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Painting.
Beginning steps - deciding what you want to build.
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About ten years ago, I sprayed an old bike with acrylic lacquer, bought in the form of automotive touch-up spray packs. The frame looked really nice immediately after I'd painted it, but I found the finish to be rather less than durable. With this frame, given that I'd put so much work into it, I wanted the very best paint finish I could buy. People on the framebuilders mailing list recommended Dupont Imron as a really durable, high quality finish. This paint is used by many of the top US builders and painters, such as Joe Bell The problems with using Imron is that it's highly toxic to use, very expensive, and difficult to get (at least here in Australia). Imron is a polyester epoxy paint. This means it uses two parts; the colour and an activator, that are mixed just prior to spraying. The activator is the nasty bit, containing isocyanates. In order to paint a bike you need a reasonable collection of bits:
Once I was satisfied that the frame was clean, I then washed it with "Wax and grease remover", a solvent that I'd bought from the local automotive shop. This stuff is similar to lacquer thinners, and dissolves any grease and gunge that may be on the frame. I then taped up the bits that I didn't want painted (the fork-end faces, and the inside of the head tube, seat tube, and bottom bracket). I then set up an area to paint in. I used my garage, and hung a huge canvas drop sheet on the wall, to catch the majority of overspray. I also set up an old fan in the garage, to move the air around as much as possible, and so hopefully remove some of the toxic fumes. I spent an hour cleaning up and vacuuming everything I could, to minimise contributors to dust. Once I was satisfied that the garage was ready, I brought my frame in, and mounted it on a simple stand I'd created, by clamping a broom handle in my workmate. The frame then sat upside down with the broomhandle up the seat post. After a final wipe down with more wax and grease remover (with a fresh cloth), I was ready to go. I donned my respirator, put on safety goggles, and mixed some primer with it's activator, as recommended. I started the compressor and, after a couple of experimental sprays on a tube to get the spray pattern right, primed the frame. I treated each tube as a four sided thing, in order to get an even coat, and layed down a good solid coat.
 I waited again for it to dry, then applied my decals. This was fairly simple to do. I simply cut the decals out of the sheet one at a time, soaked them in water for about thirty seconds, and then held them in position on the frame, and drew the backing off, while pressing them into the frame. On the larger ones, a thin clear coat over the top helped immensely, as the decals themselves are very fragile. Next, I sprayed some clear coat over the decals, then rubbed them back a little, so as to blend the decals into the frame. In a couple of spots, I went straight through the decals, caused by my not being thorough enough in removing air bubbles when applying the decals. This was fixed by removing the decal entirely, and rubbing the area back to the white colour coat with 400 grit paper, then putting on a fresh decal. Once I was satisfied with the decals, I rubbed the entire frame back with 800 grit, used wet, and then washed it very thoroughly, first with water with washing detergent, then rinsed with water, and finally with the wax and grease remover. I took a deep breath and did a final clear coat. This time I warmed the paint up by standing the gun in hot water before adding the activator, increased the air pressure to 60psi, and sprayed a nice thin coat over the whole frame. I achieved a pretty good gloss, except for a patch on the top of the top tube, and on the top of the down tube, which was facing downward when I sprayed, and didn't get quite enough paint to gloss. So finally, some pictures of the finished article:
 
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