Step 1.
Remove any loose resin/ash from the pipe.
Hold the pipe upside down, and gently tap the piece to remove any remaining particles. Use a pipe cleaner, cotton swab, needle, or other thin object to remove any large, stuck bits of resin that you can reach.
Step 2.
Fill a glass bowl with isopropyl (rubbing) alcohol.
Purchase 90% isopropyl, as it will clean the pipe quicker. Place the pipe inside the bowl, making sure it is fully submerged in the fluid and no air bubbles are trapped inside the pipe. Allow the pipe to sit in alcohol anywhere from 60 minutes to two hours. Rubbing alcohol will break down the tar and resin, making it easier to remove from inside the pipe. Over time, this can also clean off stains.
Step 3.
Add 1 tablespoon of salt to the alcohol in the bowl.
Salt will act like an abrasive scrubber on your pipe, lifting away the resin in places you can’t reach with a cleaning tool. Use the biggest grains of salt you can find. Coarse or kosher salt is the preferred choice.
Step 4.
Agitate the pipe in the bowl, making sure to work the salt into the inside of the pipe.
You can also pour salt directly into the pipe and after using your fingers to close off the openings, shake vigorously. Be aware of your surroundings so you don’t accidentally hit your glass on something! Keep shaking to get rid of as much resin as possible. Until the desired results are achieved, continue to soak
your pipe in the alcohol and shake.
Step 5.
Remove the salt and alcohol.
Remove the salt and alcohol from the pipe with hot water and dispose of it someplace safe, as the odor can be potent.
Step 6.
Clean any remaining spots with a pipe cleaner or cotton swab.
Wipe off any tough remaining spots by dipping a cotton swab in alcohol and scrubbing them. To remove any watermarks, soak the pipe for 10-15 minutes in a mixture of warm water and lemon juice. This will leave your glass shining beautifully.