3D Printed Smoke Bomb/Grenade Movie Prop

Note: This prop does not actually smoke and you should not try to make it do so. This is a prop, for imaginary use only.

I was recently making a movie, and I needed a smoke bomb prop for the role. I did not have one so I made one. If you have any questions, do not hesitate to ask! I check the comments section every no and then. I am sorry I could not do a video for this instructable, because I know that most of you, (including me) like videos. Anyway, here is how I made it:

Step 1: Materials and Tools

The materials for this project are:

• Green spray paint (I used Krylon Short Cuts from Hobby Lobby)

• Silver spray paint (also Krylon Short Cuts from Hobby Lobby)

• Painter's tape

• Each of the 3D printed parts (Body, Cap, Clip, Lever, Ring, and Pin)

• Hot glue

The tools for the project are as follows:

• Heat gun

• Hot glue gun

• Sandpaper (I used 60 and 120 grit, but 60, 80, and 120 is preferable)

Extras (I forgot to include these in the picture):

• Drill

• 11/32 Drill bit (something bigger will also work, but not a smaller bit)

• Pliers or scissors

• Knife

• Fine point paint brush

• 3D printer

Note: things will go much faster if you use an electric sander for this project, but I didn't have access to one at the time.

Let's get started!

Step 2: 3D Printing

Materials/tools needed for this step:

• 3D printer

Download all of these files and print them. All of the pieces have Raft/Support, and these are the percent fill of all the pieces: "Body": 3%, "Cap": 100%, "Clip": 100%, "Lever": 100%, "Pin": 100%, and "Ring": 100%. Print all of these, which will take at least 4 hours (The body takes about 3 hours). I used a Flashforge Creator Pro, which is programed with Makerbot.

Step 3: Drilling and Sanding

Materials/tools needed for this step:

• Sandpaper

• Drill

• 11/32 drill bit

• Each of the 3D printed parts

Fit the Clip and the lever together, and drill through the larger hole. Now you may sand all of the pieces except the pin. Be careful! The lever has 2 very fragile pieces. So when you are sanding, try not to break them! If they do break though, the smoke bomb will not look very different, and it will still work. Once you have the pieces to the desired smoothness, you can fit them all (except the pin and ring) together as shown in the 5th picture. Is there something wrong with it? Yes! the lever is straight! it should be bent. That is for the next step.

Step 4: Heat Gun

Materials/tools needed for this step:

• Heat gun

• Each of the 3D printed parts

Assemble everything together and mark where the lever and the body almost touch, and use the heat gun to soften the lever and bend it so that it resembles the 3rd picture. Then use the heat gun on the pin, and bend into a "U" shape as shown in the 5th picture. Keep heating and bending until you have something that looks like the 6th photo. Fit the lever and the clip together, and push the pin through to make sure it fits. Do not worry about the end of the pin that sticks out the other end, because we will fix that later. You can fit everything back together, as in the 9th picture, and it should look close to the picture. The last picture is what you should have if you have finished the last 4 steps.

Step 5: Painting!

Materials/tools needed for this step:

• Green spray paint

• Silver spray paint

• Painter's tape

The body will be green and the rim of the body will be painted silver, and all the other pieces are silver. Note: If you want the rim of the body to be silver, you must paint the green part first, as shown in picture 2. I wanted to do 2 coats on the body, so I painted that first. After painting the other pieces, I came back to the body and did a second coat of green. After that dried, I lined up the painter's tape with the rim on the bottom. I then stuck more tape up to the top of the body. After that, I sprayed the rim with silver and pulled the tape off while it was still wet, so that it did not pull any paint away. Now on to the next step.

Step 6: Assembling the Clip

Materials/tools needed for this step:

• Heat gun

• Hot glue gun

• Hot glue

• Each of the 3D printed parts

• Pliers/scissors

While you are waiting for the body to dry, plug in the hot glue gun, and slide the ring into the pin and fit that through the lever and the clip. Then cut it with the pliers or scissors about 1/2 an inch from the clip. Use the heat gun to soften the pin, then bend the pin up in an "L" shape. Only 2 more steps left!

Step 7: Assembling and Gluing

Materials/tools needed for this step:

• Hot glue gun

• Hot glue

• Each of the 3D printed parts

Turn the cap upside down and put a ring of hot glue on the bottom, then center it on the top of the body. Push it down and let the glue set, then squeeze a generous helping of hot glue on the top of the cap. After that, push the assembled clip onto the cap as shown in pictures 5 and 6. When that is dried, add more hot glue around the bottom of the clip, and try to make it look as if it is a weld bead. Picture 7 shows what it should look like when you are done.

Step 8: Touch-ups

Materials/tools needed for this step:

• Green spray paint

• Silver spray paint

• Knife or other pointy object

• Fine point paint brush make sure you don't care a whole lot about you brush, as it will probably become permanently silver)

• Smoke bomb

Using the knife, carefully scrape away any hot glue that you don't want. Then, since there is almost always parts where the paint didn't go on, or the paint got scratched off, you will need to touch up the smoke bomb. What I did is spray some of the paint onto a piece of paper and then use a fine tip paint brush to paint on where the spray paint did not get. You also need to paint the hot glue weld, and the end of the pin. I also decided to make some scratches using the knife as in picture 6.

Step 9: Conclusion

Materials/tools needed for this step:

• Smoke bomb

I really liked how this smoke bomb worked. It turned out almost better than I expected! If you have any questions, do not hesitate to ask, and I will receive an E-mail telling me when you comment. I check my inbox frequently, so your question should be answered soon after asking it.