You don't need much to do it, a faucet, preferably a toilet, and some sort of baggy that will contain a liquid (Zip lock are best, even fold top baggies will work.) If you don't have some, you will need to buy some Isopropyl alcohol. It's cheap ($1.50-$2.50) and effective. Alchohol absorbs THC. The higher the alcohol percentage, the better.
The last thing you will need, is salt. The purpose of the salt is that it will act as an abrasive, to help "scrape" the resin off the piece, when poured in to the liquid. You're going to want a shaker with a removable cap, or the container you fill your shakers with.
If your pipe is more than just dirty, it's straight up clogged, or has a large amount of resin buildup; You may need to find some sort of additional scraping tool. Pipe cleaners are an obvious choice, bent paper clips can work, and won't hurt your pipe.
How to clean pipes (metal, glass, ceramic) downstems, bowls, ash catchers, one hitters, bubblers, etc;
Fill your plastic baggy with your Iso alcohol enough to approximately cover your piece.
Add some salt (just enough so that you can see some salt which hasn't dissolved in the alcohol, AKA reached it's peak saturation. You may not need or want to use quite this much though, which is alright) in with the alcohol.
Place your piece in the mixture, and shake. As it works, the mixture will start turning to a brownish, rather bad smelling liquid. If progress is slow, let it sit for some time, then resume shaking.
Drain the liquid in to your toilet and flush, then rinse your pipe with warm water. If it's not clean enough, repeat the baggy procedure. Make sure to rinse thuroughly.
Optional; If you would like to take one more step, you can do the same baggy procedure, but with hot water (not boiling, as hot as your faucet can get or near abouts will do) instead of Iso alcohol. This is preferably done before the alcohol. Afterwords, do it with the alcochol.
How to clean bongs;
The premise is the same as with pipes and everything else.
In this case, you want to be over a toilet, sink, bathtub, something to catch any accidetnally spilled water. You'll regret it if it happens on a carpet, trust me.
Fill your bong with hot water (not boiling) because some if not most bongs will need this extra step to get a good cleaning, to a few inches below where your stem meets the bong. Add in salt. Cover your bowl/stem, and the bongs mouth opening, and shake. Rotate and flip the bong upside down while shaking. As most buildup will be near the stem, let sit for awhile if nescessary.
Drain the water in to a toilet, and then repeat using Iso alcohol. Again, make sure to thuroughly rinse the bong, inside and out. If you want to, you can finish it off with some scented dish soap or all purpose cleaner, to help cover any remaining bad taste in the bong.
Why you should never boil pipes;
Glass is brittle. Heating it up and allowing it to cool, in such an extreme manner, can form cracks, or help to mature any potential weak spots. Also, if the water is boiling at a high temperature, the bubbles can knock your piece around, and if it's glass, that's not a very good scenario.
Metal you'd probably get away with, but avoid it with essentially any other material.
Edited by trikky, 13 August 2008 - 08:29 PM.
Went ahead and deleted acrylic from this list of what can be cleaned with Isopropyl Alcohol.