How to Make a Gravity Bong

Gravity bongs are simple to make and they’re a fantastic device for stretching out the smoking potential of your dried herbs. They’re also known for being extremely effective, so be sure to have a good supply of snacks and lounge areas on hand to get you through the initial buzz. Several people can use a gravity bong at once with a surprisingly small amount of dried, so these devices are great for those on a budget or anyone just looking for a fun new way to smoke. Gravity bongs work by slowly raising and lowering a two-liter bottle into water, and you’ll learn exactly how to make a gravity bong below.

What You'll Need To Get Started

  • 1 two-liter plastic bottle (the kind soda comes in). Make sure you have the cap, too
  • Sturdy scissors or a sharp knife. A serrated knife is ideal
  • 1 bucket or container wide enough to hold the two-liter bottle
  • 1 glass, metal, or aluminum foil bowl for a pipe or bong
  • A screen for the bowl, if needed
  • A lighter

STEP 1: Empty & Rinse Bottle

Empty the two-liter bottle, and rinse it out well with water. Next, get your scissors or knife and carefully cut the bottom 1/3 off the bottle. You won’t need that bottom 1/3, so set it aside and direct your attention to the piece of the bottle with the cap on it.

STEP 2: Remove Cap From Bottle

If you have a bowl for the gravity bong, make two slits in the shape of an X on the top of the bottle cap. The slits should be as wide as the bowl. If you’re using aluminum foil, you’ll need to punch a hole in the top of the bottle cap. A drill is perfect for this, but a knife will work. The hole should be at least a half inch wide.

STEP 3: Insert The Bowl

Take your lighter and warm/slightly melt the top of the cap in the middle of the X made by the slits you cut. When the plastic is soft, slide the bowl into the center of the X and press down until it makes a good seal with the cap. You definitely want the bowl to be on the top side of the cap, not the bottom. If you’re using foil, tear or cut a piece large enough to make a bowl that fits snugly into the hole you made, and then poke some holes in it to allow smoke through. When you’re done, screw the cap back onto the bottle.

STEP 4: Add Water To Bucket Or Sink

Fill your bucket/large pot/sink with at least five inches of water. You can experiment with how much water works best for you, but 5 inches is the bare minimum here.

STEP 5: Add Water To Gravity Bong

Place the open end of the bottle in the water, preferably as close to the bottom as possible. There should be at least an inch or two of air left at the top of the bottle when it’s resting on the bottom of the water, so adjust the amount of water you have if the bottle fills up all the way.

STEP 6: Load The Bowl

Once you’ve figured out how much water you need, and there’s no danger of water flowing up into the bottle and getting your pot wet, go ahead and load your bowl with the desired amount of dried herb.

STEP 7: Light The Bowl & Enjoy

Light the dried herb as you very slowly draw the bottle straight up but not all the way out of the water. It’s important to keep it in the water to prevent the smoke from escaping. When the bottle is full of smoke, unscrew the cap, put your mouth on the bottle, and slowly push it back into the water, inhaling the smoke. Pushing the bottle down will force the smoke out of the bottle and deep into your lungs.

Sit back and enjoy the intense rush that results from knowing how to make a gravity bong.

Helpful Tips

  • You’ll need to replace the bottle after the wear and tear of multiple uses, but a well-made cap/bowl can and should last a long time. Learning how to make a gravity bong is relatively easy, but making a really good cap takes practice. Don’t worry if your first one isn’t perfect
  • If your cap/bowl construction isn’t airtight, you can use tape or a sealant to seal the gaps. Be aware that this is a temporary measure though, and heat will inevitably break the seal after a few uses
  • Warming the plastic on the cap with your lighter until it becomes slightly soft will make the initial X-shaped cuts or hole easier to do. This will also help you make more precise cuts. The plastic will need to be heated a little more after that to position the bowl, if you’re using one
  • A socket from a socket wrench set makes an excellent substitution for a metal bowl. A size 14 or 15 bolt also works well
  • If you’re using a gravity bong for the first time, go ahead and do a few trial runs without packing the bowl just to get the hang of it. You really don’t want to get the cap wet, tip over your bucket, or otherwise, mess things up with a bowl full of precious marijuana

Important Considerations & Warnings

  • Finding a good burn rate is essential for getting the most out of your gravity bong. If you pull the bottle up too quickly, the contents of the bowl might not get completely burned, but if you pull up to slowly, you can lose smoke into the air. After learning how to make a gravity bong, knowing how to operate it correctly is important, too
  • Keeping your gravity bong clean is important for a pleasant smoking experience. Replace the bottle when it starts to give the smoke a bad taste and clean your caps frequently
  • Gravity bongs force a lot of smoke into your lungs very quickly, so don’t be surprised if you cough quite a bit. Be prepared when using gravity bongs with novice smokers, as they will likely get extremely high almost immediately. Even if you’re an experienced smoker, try not to take a giant hit right after figuring out how to make a gravity bong for the first time. After a hit or two, you’ll have a firm grasp on what you’re dealing with
  • Aluminum foil is okay to use for smoking occasionally if you don’t have a bowl or filter, but try not to use it too much in the long term. The foil isn’t entirely flame resistant, and it releases chemicals with unknown health effects after it’s been lit a few times. When learning how to make a gravity bong, it’s best to start with a glass or metal bowl, if possible

How To Make A Gravity Bong Guide: What Is A Gravity Bong, Anyways?

Gravity bongs became popular in the 90’s, and people began exploring how to make a gravity bong sometime around the evolution of the beer bong. The name comes from the idea that gravity is propelling smoke into your lungs at a mind-numbing rate, but it’s also a good way to explain the force of the high that’s about to hit you when you smoke out of one. The force at work in a gravity bong is actually pressured instead of gravity, but “pressure bong” doesn’t sound nearly as much fun.

This article explains one popular method for making a gravity bong, but there are lots of other ways. Some people like to use a smaller bottle for a less intense hit, and some like to use a milk jug. There are a variety of ways to affix the bowl to the cap, and it’s good to experiment until you find the way that suits you best. There’s also a method for making a similar device known as a “waterfall bong” that uses only one bottle and no outside water source. Waterfall bongs are fun to use and give a great high, but they’re a little harder to make than the super-simple gravity bong. If you’re new to making smoking devices, starting with learning how to make a gravity bong is a great choice.

Gravity bongs are an entertaining group activity, and they’re perfect for parties. Even if you just a have a few friends around, you can all get ridiculously high with a small amount of dried herb. These bongs don’t filter smoke like regular bongs, so the result can be a little harsh. Still, this is an excellent way to have fun with your friends, and learning how to make a gravity bong out of a variety of materials is a life skill that will benefit you through the years. Once you’ve got the hang of it, making one takes less than ten minutes, and there’s a certain satisfaction that comes with knowing you’ve made a totally satisfying smoking device out of common household materials. Be careful with your gravity bong, since it will deliver a powerful high, but most of all, have fun with it.

For more guides, check out our Ultimate Guide to Bongs or our Guide to Dab Rigs!


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