There are lots of PVC crossbow how-to tutorials, but I found none that were satisfyingly powerful, simple to build, and constructed primarily out of PVC. This crossbow is all of that, and stylishly designed! All you need are common household tools and materials (and perhaps a better way to film your crossbow in action).
If you like this project, then check out my book Duct Tape Engineer! It's full of large-scale duct tape contraptions.
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Step 1: Tools and Materials
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- Metal measuring stick
- PVC pipe cutters
- 84" of 1/2" PVC pipe
- Heavy duty duct tape
- 36" of paracord
- Drill with 1/2" bit, and a bit that is slightly wider than your paracord
- Hot glue gun
- Utility knife
- Hacksaw or other tool for cutting into PVC
- Safety goggles
- Medium binder clip
- Metal spoon*
- 16 gauge mechanics wire
- 1/4" dowel
- pencil sharpener
- index card
- (optional) decorative duct tape
*Find a spoon with a wide, flat handle that is difficult to bend
Step 2: Build the Stock
Prepare the pieces
- Cut three 20" pieces of 1/2" PVC for the stock
- Cut one 24" piece of 1/2" PVC for the bow
Assemble the stock
- Bundle the three 20" pieces of PVC, then wrap the ends in duct tape.
- Press the tape into the grooves as you wrap the tape around. This will ensure that at least one side will have a grooved channel to help guide the crossbow bolt.
- Apply three 20" pieces of duct tape along all three grooves in the stock. Again, press the tape into the grooves as shown.
Step 3: Attach the Bow
Attach the bow
- Cover the 24" piece of PVC completely with duct tape. This will help prevent the pipe from releasing shrapnel if it breaks.
- Measure and mark the center of the bow, then line it up with one end of the stock. Tightly wrap a piece of duct tape around the front of the stock, securing the bow in place. Again, press the tape into the groove.
- Wrap a second piece of tape around the first piece of tape and the stock. The image above depicts this step using white duct tape. And yes, press it into the groove.
- Repeat steps 1-2 again to form a strong joint. This part of the crossbow will be under stress, and two layers of tape will help prevent it from ripping over time.
Step 4: String the Bow
The following technique keeps the bowstring pressed against the top of the stock, which will help ensure that the crossbow fires consistently. It's also an easy way to create a very secure attachment that won't come undone over time.
String the bow
- Using the drill bit that is slightly wider than your paracord, drill a hole into each end of the bow.
- Insert one end of the paracord into the hole and push it toward the front of the bow, then pull it through. You may use a bit of wire to help push the paracord through if it's a tight fit.
- Loop the paracord around itself as shown in the first picture.
- Make sure the bowstring is pulled toward the underside of the bow. Wrap the paracord tightly around the bow several times, but do not wrap it around the bowstring. On the last wrap, apply hot glue onto the bow and adhere the paracord to it.
- Wait for the glue to dry, then repeat on the other side while pulling the bowstring taut. It is much easier to do this step with a friend: Have one person keep the bowstring taut while the other attaches it to the bow.
Step 5: Create and Test the Trigger Groove
Sawing PVC is messy. Make sure you work over an area that is easy to clean, and have a vacuum on hand.
Create the trigger groove
- Measure 14" from the very front of the bow and mark a spot on top of the stock.
- Cut away about 1/2" of duct tape between 14 and 14.5" around the top of the stock with the utility knife. This will help prevent the tape from gumming up your saw.
- Saw straight down about 1/2" into the stock at the 14" mark.
- Saw diagonally at the 14.5" mark toward the first cut as shown in the first image.
- Clean up the PVC debris.
Test the trigger groove
- Wear safety goggles for this step. The PVC may break and release very sharp pieces of shrapnel toward you.
- Press the back of the stock into the ground, and grasp the bowstring in both hands.
- Slowly push the bowstring down as shown until it slips into the trigger groove.
- Leave the bowstring in the trigger groove for 5 minutes. This will help the PVC bend into it's natural resting state, making it easier to load in the future.
It will require upwards of 40lbs of force to string the bow the first time, and it may feel a little unnerving to see the PVC bend so much. Put on your goggles and push hard!
Step 6: Build the Trigger and Bolt Clip
Build the trigger
- Cut away the tape where the trigger hole will be drilled as shown.
- Using the 1/2" drill bit, drill a hole in the center of the stock in front of the trigger groove. This step may be challenging; the drill bit may slip out of place. To prevent this, use one hand to tightly grasp the stock to prevent the pipe from being pushed apart by the force of the drill. Work slowly and diligently
- Tape a handle of the medium binder clip just behind the trigger groove.
- Tape a spoon onto the other binder clip handle such that the spoon handle rests just below the trigger hole.
- Test it: Push on the spoon and make sure that the spoon handle lifts out through the trigger hole.
- If desired, bend the spoon into a more comfortable position as shown.
Build the bolt clip
- Cut an 8" piece of wire and tape both ends on either side of the binder clip.
- Bend the wire so it presses onto the center of the stock. This will keep bolts in place while you take aim.
Step 7: Make Crossbow Bolts
Make crossbow bolts
- Cut a 1/4" dowel to about 13" and sharpen one end with a pencil sharpener.
- Split the other end with a utility knife, then carefully insert a small piece of wood or pebble as shown.
- Tightly wrap duct tape around the split, leaving about 1" of split wood. This nock is where the bowstring will catch onto the bolt.
- Tightly wrap about 5" of wire around the tip of the bolt. This extra weight will help "pull" the bolt through the air with its momentum.
- Cut two triangular fins out of an index card, then tape them to the back of the bolt.
- Make sure the fins are aligned with the nock as shown. It's also important that they are opposite of each other and perfectly straight. Cover the fins in tape to add longevity.
Step 8: Load and Fire!
How to load and fire
- Press the back of the stock against your hip and pull the bowstring into the trigger as shown in the video.
- Position the bolt under the bolt clip, directly in front of the trigger hole. From this step onward, do not aim the crossbow at anyone.
- Squeeze the spoon trigger to release the bowstring and fire the bolt!
Runner Up in the
Make It Fly Contest 2016