The story behind this particular project starts at a trip to one of my favorite record collecting spots - the local flea market. Generally, I don't bother with the regular vendors, instead I go straight to the weekend warrior booths, your everyday Joe's selling random crap from their house. This one guy was selling an old Craftsman toolbox, a really nice metal one from who knows when for $2.00. I bought that one for the $2.00 and he threw in this one for an extra $1.00. Three dollars, why not. This particular box was in pretty decent shape apart from the rough looking paint job. This particular tutorial will be specifically for this tool box. I will detail how to remove the old paint, some light rust which coated the bottom of the box, and also the painting procedure. I will give reasoning for why I decided to do what I did as well. Of course, any questions regarding why I did what, or whatever, feel free to ask in the comments. Being my first post of this sort, I may not have pictures for every specific step but I will ultimately try to accompany most of the main steps with some sort of images. Anyway, those wondering about my record finds from that specific trip will be pretty disappointed. I picked up two VHS tapes, Tales from the Darkside Volume 4 and 1981's Ghost Story. Music wise, only two cassettes were to be nabbed that day, Dokken's Back for the Attack and Def Leppard's Hysteria. Anyway...
The first thing that I had to do with this particular tool box was to remove the old paint that looked worn, scratched, and generally deplorable in every way. There are two methods for removing paint like this from metal. The first would be to use a stripping agent such as Jasco's Paint Remover. I personally don't like using a paint remover for something I plan on repainting. Paint removers leave a residue which, if not removed correctly, will affect how the second coat adheres to the metal. You can always use an afterwash solution, but it's just another step and you wind up with a messy clump of liquid and paint. For this box, I decided to use a wire brush drill attachment to remove the paint on the box. First, I own several drills so there was no added cost to me having the necessary hardware. Strippers and an afterwash would add up to roughly $11.00 or more.
The wire brush attachment I bought was $2.50. I actually bought two, a smaller style attachment to reach into the corners inside the box. I got two attachments which I can use over and over again, in many different situations, for half the cost of the liquid solutions. The left brush is a coarser haired wire brush which I used on the flat surfaces of the box and generally everywhere that I could. It not only strips the paint faster than a fine grit brush would, but it also leaves a slightly rougher finish on the metal, giving the paint a better surface to adhere to. I used the finer wire brush (right) to do some small touch up on the metal hardware without removing too much of the patina. It ultimately resulted in a more consistent finish on the parts of the box that I knew I wasn't going to paint. For instance, the name plate on the top of the box, I wanted to leave with the oldish patina but there was some slight rust in the corners near where the handle is located. I used the fine brush to remove the rust, while leaving the patina.
I started removing the paint on the outside of the box. Of course, I wore a general purpose mask to prevent me from breathing in the small particles of paint which are never a good thing to breath in for many reasons, mostly Lead. It's also a good idea to wear some sort of eye protection. In my case, I also wore a pair of work gloves so should the wire brush come in contact with my hands, which did happen on several occasions, I would still have some sort of epidermis left. If you are really clumsy, you may want to also wear some sort of arm protection. I happened to briefly nick my arm with the brush and it left about seventeen thousand hairline scratches.
If you're a big strong tough guy like me, feel free to do this whole process in the nude, wearing no shoes, no face mask and while consuming your favorite cold beverage. Ultimately for my particular project the two most important liquids to have on hand were my 1/2 pint of paint and my 12oz bottle of Stone Pale ale. Of course, the other liquid which is necessary unless you want to keep buying paint brushes over and over again for eternity is a can of Mineral Spirits.
The finished exterior of my box. The exterior of my box took me approximately forty minutes to strip the paint from. If you really like the stainless steel look, you could actually just leave the box like this. It would be more susceptible to further rust without a protective coat however. For a real professional look, you would ideally want to use some sort of polishing powder or tool to give it a real smooth finish. Unfortunately, I did not take more pictures of this in progress. 
On the larger tool box, I will be sure to take more pictures, but then again, that is an entirely different project, quite a bit more difficult than this box. Anyway, with the outside of the box completely stripped I turned my attention to the inside of the box. Generally speaking the inside of something is always harder to work on than the outside. It is more difficult to get into the tighter spaces with tools specifically. I used an extension tool for my wire brush so that I had more room to maneuver within the box itself. 
There really is no right or wrong way to go about it. You can do the inside, then the outside, you can start on the lid or the bottom... whatever floats your canoe. I happened to start on the bottom first. The previous painter had painted the hardware so I made sure to get at that with the fine wire brush. To get in the corners, I actually couldn't fit the coarse brush so I just jammed the fine brush in the corners and removed the paint with that. There was a tiny small area of paint left there which I scraped off manually with some 60 grit sandpaper I had lying around.
Voila, the finished stripped box. All paint removed. The total time to remove all the paint on this box took about an hour and forty five minutes. I also think I took a minute of that to get a second beer. After finishing removing the old paint I took a damp rag and just removed any of the remaining dust from the metal so that I would have a completely clean surface to paint.
Before going ahead with painting the box, here are some more close up images of the box totally stripped. First, is the plate on the box showing the handle - very easily - disassembled.
I found it much easier to strip the stop of the box by removing the metal handle from it's holders just by using a little extra force to get it out. If you can remove hardware with ease, do it. Breaking down something into separate parts will make everything move along smoother and you don't have to worry about accidentally ruining a part of whatever you're working on.
Another picture of the plate on the box, showing the patina I wanted to leave as is. I felt it gave the box a bit of an antique-y feel and added a bit of detail to the box.
So we are ready to paint the box. I used a Purdy one inch brush for this project and for some of the really small details, I used hobby brushes - a #2 and #4. For this specific project, I saw no reason to prime the metal surface before applying my paint. The surface was already rough, due to the stripping of the older paint and I don't plan on having this box outside, in a situation that would endorse rust appreciation and the material was uniform across the whole project. If I planned on keeping this box in a place with high humidity, or outside or in an environment which would be more harsh than normal, using a clean metal primer would increase the already excellent protection from rust that your standard oil based enamel would provide. I would not use a latex based paint on a project such as this. For a small box like this, you only need a small amount of paint. I chose a gloss (shiny) finish and tinted the paint towards an industrial-gray-green color. Oil based paints are practically impossible to remove from clothing should you get some on a shirt or pants. Trust me, wear something you don't mind getting dirty.
I painted the inside of my box first. No reason to start there, I just thought it a good place to start. I specifically decided to leave the hardware with the metal showing. The rivets holding the company plate on the top of the box, the hinges and the front latch I left completely unpainted. I applied my first coat on the inside of the box and allowed for twenty-four hours to dry as directed on the can. 
I then proceeded to do a second coat to get a consistent finish across the whole surface. Be wary of applying too much paint at once to vertical surfaces. Over application will cause dripping marks. It's better to apply a thinner coat of paint, and do several thin coats and get a clean finish than to apply one massive thick coat and just get it done. On flat surfaces, this is not a problem and I often apply a thicker coat to surfaces such as the bottom of the box so I have less to touch up on the second coat. Be careful around detail spots such as hardware. If you are uncomfortable "cutting in" around tight spots with a larger brush, use a fine detail brush to get in the small areas. Remember, it's better to be careful than have to try and remove paint from a surface. Oil enamels are incredibly durable and a pain to remove from places where you don't want paint.
The most important part of doing a job like this, is making sure you clean your brushes properly after each coat. Paint brushes can be expensive, especially high quality brushes. Do not use a chip brush, or a cheap brush on a project like this. Chip brushes are generally one-time use brushes and have coarse hairs which leave unsightly hair marks on your finish. Cheap brushes work for a few coats but wear down when using chemicals to clean them - a required part of cleaning paints, particularly specialty paints such as oil based primers and enamels. For latex paints, economy brushes are acceptable at times but, if you use a premium quality brush, you will not have to buy brushes after each project and you can reuse them, over and over again.
For cleaning oil paints, mineral spirits an ideal 
solution to clean brushes. Pour a little amount into a cup, shake your brush around and you should be able to remove all the oils from the brush. After wards, rinse the brush in warm water with soap. Don't let the brush sit in the mineral spirits and rinse the brush immediately after painting. Oils are impossible to remove after they have dried and will ultimately cause you more trouble than is worth. You'll be forced to just buy another brush. After washing the brush, just let it hang on a peg hook or wherever to allow it to air dry.
I let the inside of the box dry completely before working on the outside. I did the outside part of the box in two steps. I applied paint to the upper three-quarters of the box first and did my recoat and then I finished the bottom of the box in the same manner. I then waited another twenty-four hours before reattaching the handle or handling the box. I cleaned my brushes after each coat, the same way as I described above and completed the box. The total project took me about four and a half hours excluding drying time. With drying time, I spent about 3 days, letting the painted parts dry for a full day between coats Here are some completed images of the tool box:
Finished Box without handle
Finished face plate without handle
Finished box with handle
Open Finished Box
