In my journey of smoking marijuana, there is one tool that I like best, whether it is at home or in a hookah bar, it captures my heart and gives us instant high: I can even use it to get a more intense experience with a minimum amount of material, are you wondering now what is the tool that has this magic? That’s right: the gravity bong!
This homemade device uses gravity and water displacement to deliver concentrated hits. The gravity bong quickly presses large amounts of smoke into your lungs, making this a fun cannabis smoking tool that I think is well worth the time it takes to make, and much more so than the regular bong. It’s much better than the regular style bong. As a result, I have a house full of gravity bongs of all kinds. Forever. If you’d like to have the same variety of DIY gravity bongs that I do, then read on!
Next, we need to learn to make a gravity bong from scratch. The first major challenge we face is to prepare the necessary materials
Materials for making gravity bong
- Empty plastic bottle (larger bottles work best)
- Scissors or box cutter
- Larger container (bucket, sink, or another bottle)
- Downstem and Bowl (Recommended): Using a proper glass downstem and bowl that fits snugly into the bottle cap is highly recommended. If you don’t know where to buy it, I suggest you check out GRAV‘s website.They offer a variety of bowls, including the 14mm Helix Multi One-Hitter Bowl, which is suitable for testing a new bong—I swear you’ll love it.
- Toothpick or sharp object (for making holes)

Of course, you can also choose the following products to help you better increase your experience:
For example, electrical tape or duct tape, but I prefer electrical tape. That being said, don’t let my love for electrical tape stop you from giving up on your ideas. You can choose according to your needs.
These materials can help us effectively fix the bowl on the bottle cap, or form a more airtight seal between the bottle and the bottle cap.I think this is the most important step in our process of making bong

Steps to make gravity bong
First, before cutting, we first determine where to cut the bottle. In my opinion, it is better to cut about halfway through the bottle. So here let’s use a marker to draw a clear straight line on the circumference of the bottle where you want to cut. This will help us get a cleaner and more even cut next. The following picture shows the straight line we drew, which is perfect. Then I need to use the Box Cutter to cut
extend the blade only slightly to avoid accidental deep cuts. Carefully score along the marked line several times, gradually deepening the cut until you slice all the way through.This is when you have to stay calm and make yourself as stable as possible.
Smoothing the Edge: Once the bottle is cut, inspect the cut edge. If it’s jagged or uneven, carefully trim any rough spots with the scissors to create a smoother surface.
Discard the Bottom: Safely dispose of the bottom half of the bottle. I think this is not what we need
Cap Modification: Precise Hole for Secure Fit (Downstem Focus)
Centering the Hole: Identify the exact center of the bottle cap. Use a marker to place a clear dot in the center.
Starting the Hole: Use the tip of the scissors or box cutter (very carefully!) to create a small pilot hole in the center of the cap, precisely on your marked dot. A box cutter is only needed for the initial small hole.
Gradual Enlargement: The goal is to create a hole that perfectly fits your downstem. Gradually enlarge the hole using the scissors, working your way around the circumference of the pilot hole. Test the fit of the downstem frequently as you enlarge the hole.

Next, we need to insert the downstem into the hole we just made, after inserting the downtube, test the seal by submerging the cap in water and gently blowingit into the downtube. Check for air bubbles escaping around the downstem, if you also have bubbles as in the picture below,

that is a very bad thing, you guessed it this indicates a leak, so we chose some material to improve it (you can guess which material I will use ! 😂). Personally, I prefer to use duct tape, we can seal the leak with duct tape and it’s great! Now we can enjoy our homemade gravity bong!