I love the look of well polished brass, but the work can be daunting especially when the level of tarnish is bad. In this instructable I will tell you how I deal with the issue; it is fairly quick and quite effective. I should also note that not all brass is created equal, my method is mildly brutal so I would not use it on really expensive items without a bit of thought. Also for just a bit of tarnish less drastic methods should do. Take a look at the pictures here to see if you think it work well for you then read the next section. Also note that it can be a deeply ( but perhaps not spiritually ) satisfying experience to put a nice polish on a piece of brass ( or gold or silver if you can afford them ).

Step 1:

The Big Picture

There is more to polishing brass than just the polishing. Just what you are polishing can make a big difference. Many brass items are coated with a protective material to stop them from tarnishing. This coating often fails ( sometimes over many years ) and the tarnish gets under the coating. In order to polish the item you need to remove the coating. I have one lamp where I still have not figured out how to get the coating off, so it is still unpolished. Sometimes the coating deteriorates and is gone by the time you are ready to polish and sometimes you can use a solvent or paint remover to get it off. But this instructable is not about removing the coating, use it if:

You have determined there is no coating.
You have gotten the coating off.
Many softer coating will polish off, try to test before you go big time.

Also note that some brass object have deliberately non polished or colored areas, this technique is probably too brutal to be used on these objects.

When you have finished polishing you can either add a coating or not. If you do not add a coating plan to polish again ( on a boat perhaps next week, in a house perhaps next year ), this is what I often do. Even if you do coat the surface it will not be permanent. Again this is not an instructable about coating, but about polishing. I will give a few tips later in the instructable on coating.

A couple of other things to look out for:

Baldwin has a brass that never tarnishes, just leave it alone. ( by the way it is nice stuff if you can afford it )
All that looks like brass may not be, if plated you may detect with a magnet, polishing plate may remove the brass down to the base metal ( which may not be magnetic ).
Some objects are not meant to be bright.

Step 2: Tools and Materials

Several brands of polish … see the steps that follow.
Very fine steel wool Grade 00 or finer.
Soft cloths
Something to polish

Step 3: The First Level

This is the step is dirty, hardest part, in this you get the gross stuff of and get down to the metal. For an example I will uses an andiron that has seen many a fire over about 5 years since the last cleaning. It does not have any sort of protective coating. I will also not go for the ultimate polish, this guy is going back in the fireplace.

Brush or wipe off the item so it is reasonable to work on and then set it up at a convenient work height on a disposable surface ( perhaps newspaper )

For the first polish I use either Twinkle Brass and Copper Cream Cleaner or Kleen King. ( this instructable done with Kleen King, but I find them very similar in results ) I apply this with the fine steel wool ( see Tools and Materials ). On un-coated brass this gets down to the metal almost immediately.

When I take the first cut at the job I then decide whether or not to take the item apart. In the case of the andiron it is a fairly simple job and lets me get into spots that otherwise would be hard to reach. In a similar way it is often good to take hardware off any mounting.

Aside from the steel wool you can also use a tooth brush, string coated with polish ( use like dental floss ) or a cloth. I would not use a wire brush, sandpaper, or coarser steel wool. You may find that even the steel wool is not necessary, be a gentle as possible while still staying effective.

I polished the parts until they look pretty good then wash them off. I do not like to leave this polish ( or most polishes ) on the piece at the end of the polishing. Use you judgment about washing, I did not wash my marine barometer, I just used damp paper towels to clean it up. After washing I look for missed spots, touch them up and wash again.

Step 4: The Second Level

The first level polishing has a raw metal look without much sheen, this and the next step should correct that. We are done with the harsh stuff and the steel wool. I use Noxon Seven Metal Polish here. Apply with soft cloth and buff off. Continue while you have good results.

Do not try to get off stuff missed in the first level, if you have this be more careful earlier. Go back to the first level if it is critical for you to get off this sort of blemish. Minor stains and spots will come off.

For my andirons this was about another 10 minutes. You may re-assemble or not, I did not. You should should see a much more mellow polish with a nice sheen and a deeper surface look. I hope you can see the difference in the pictures but I can assure you it is apparent to the eye.

Step 5: The Third Level

Just like the second level, but now I move to that old favorite Brasso. Use fresh cloths and this time let the polish dry. In my case I did this with the andiron still in parts, reassembled it and did a quick repeat.

Again about 10 minutes for the step. Once more there is an improvement in the luster of the object that may or may not be apparent to you in the pictures.

Step 6: Coating?

The andirons are going in the fireplace so I elected for no coating. Also this is not an instructable about coating after polishing. I will, however, give you some quick notes:

Paste, or butchers wax ( one brand http://www.amazon.com/Johnson-Fine-Wood-Paste-00203/dp/B0000DIWIM/ ) : easy to apply, easy to remove, will stand up a bit to water. I have tried this and it seems to delay the need for re-polishing for awhile. Does not mess up the appearance of the polish job.
Future Floor Wax : is a clear acrylic that can be dissolved in water, so may protect items that do not get wet. Easy to remove. I have this on my list of things to try.
Shellac : easy on and off, dissolves in alcohol. Does not stand up well to water. Come in clear and colored. I think this will be more durable than the above, on my list of things to try.
Lacquer: hard on and off, usually sprayed. I do not think I will mess with this. Probably the most durable of the items here.

Step 7: Final Notes and More Pictures

The pictures show how some other objects turned out. I sometimes like the look best about a month after polishing when there is a very fine layer of tarnish which somehow can add even more character.

My theory of how this works is that working through the steps we are going from rougher abrasives and chemical action to finer ones so at each step the surface becomes more finely polished, perhaps a microscope could lend a hand here, in any case it seems to work. This is like using finer and finer sandpaper in finishing wood.

I have used a buffing wheel with a mild buffing compound, this can be fairly tedious and for my stuff have only occasionally used it. The wrong compound can ruin the peice.

If you try this let me know with feedback via the comments, if you have another way comment and/or do another instructable.

Happy polishing.