How to Print & Assemble The Atomic Bomb

If you want to save this How-To instruction as a pdf file (and print it out later if needed), simply copy the URL of this page and paste it to https://www.printfriendly.com/ . Printfriendly will generate a printer-friendly pdf of the page with all the texts and images for you.

All of the STL files are really straight forward to print. All you need to do is load them into your slicer software (I use Cura), select your desirable settings (e.g. layer height, infill percentage, etc.) and slice the parts. I used 0.4mm nozzle and 0.2mm layer height to print all parts of this model.

Please note: I already saved the STL for each part in the orientation I printed them on my FDM printer. Hence, when you load the STL in your slicer software, you don’t need to orientate them again, unless you want to try to print them in a different orientation.

So now you’ve got all your parts printed? Great! Let’s assemble the model!

I’ll take you through the assembly process step by step but before that, you need to purchase some items:

• 5mm dia x 3mm thick N42 Neodymium magnets (LINK) | Qty: 82-off
• 3mm dia x 2mm thick N42 Neodymium (LINK) | Qty: 28-off
• 5mm dia Steel Bearing Ball (LINK) | Qty: 1-off
• Hex Socket Cap Screw, M3 x 12mm (LINK) | Qty: 86
• Stainless Steel Hex Nut, M3 (LINK) | Qty: 50
• Brass Solid Round Rod 2mm Diameter 100mm Length (LINK) | Qty: 8-off
• Polyester Cord String 1mm dia (LINK) | Qty: 2 meters
• Super glue (LINK) | Qty: 1 bottle

At this step, all I want you to do is try to stack all the parts together to get a good understanding of where they are located. Because there are a lot of magnets you need to fit during the assembly process, doing this first step will give you an idea of how to fit the magnets in each part correctly. Please use the ‘Atomic Bomb_Core Only.stl‘ and ‘Atomic Bomb_Fully Assembled.stl’ and the photos below if required.

Parts required (refer to the photos below)

• 1x Internal Neutron Initiator (a)
• 2x Plutonium Sphere (b)
• 2x Uranium 238 (c)
• 2x Boron Plastic Shell (d)
• 2x Aluminium Pusher (e)
• 6x Magnets (3mm dia x 2mm thick) (highlighted in red)
• 6x Magnets (5mm dia x 3mm thick) (highlighted in red)

Assembly process

1. STEP 1a: Glue 3x magnets (3mm dia x 2mm thick) into the magnet holes on each half of the Uranium 238 sphere
2. STEP 1b: Glue 3x magnets (5mm dia x 3mm thick) into the magnet holes on each half of the Aluminium sphere
3. STEP 1c: Assemble all parts together.

The Internal Neutron Initiator is a 5mm Dia sphere. You can either print this part, or simply purchase and use a 5mm Dia Bearing Ball instead

Parts required (refer to the photos below)

• 20x Explosive Blocks (Inner)_Hexagon (a)
• 12x Explosive Blocks (Inner)_Pentagon (b)
• 20x Explosive Blocks (Outer)_Hexagon (c)
• 12x Explosive Blocks (Outer)_Pentagon (d)
• 70x Small Pin (e)
• 1x Inner Core from STEP 1 (f)

Assembly process:

1. STEP 2a: Press-fit 5x Small pins into the holes of a Explosive Blocks (Inner)_Pentagon
2. STEP 2b: Press-fit 5x Explosive Blocks (Inner)_Hexagon to all 5x sides of the Pentagon block above. Use small pins to interlock all blocks together
3. STEP 2c: Press-fit 5x Explosive Blocks (Inner)_Pentagon to the sub-assembly from STEP 2b. Use small pins to interlock all blocks together
4. STEP 2d: Press-fit 5x Explosive Blocks (Inner)_Hexagon to the sub-assembly from STEP 2c. Use small pins to interlock all blocks together
   

   At this point, you’ve built half of the Inner Explosive Sphere. Repeat the same steps as above to build the other half. To connect 2x halves of the sphere together, you can either use the small pins, or some 5mm dia x 3mm thick magnets. The Outer Explosive Sphere can be built following the exact same steps as the Inner one above

5. STEP 2e: Assemble the Inner Core from STEP 1, Inner Explosive Sphere, and Outer Explosive Sphere together
   

   The sub-assembly that you’ve just completed at this step is referred to as the “Physics Package“

Parts required (refer to the photos below)

• 1x Forward Cone (a)
• 2x Front&Rear Polar Cap (b)
• 1x Side Case Segment (Top) (c)
• 4x Side Case Segment (d)
• 1x Suspension Lug (e)
• 1x Aft Cone (f)
• 1x “Physics Package” from STEP 2 (g)
• 66x M3-12-Cap Screw (h)
• 50x M3 Nut (i)
• 12x Magnets (5mm dia x 3mm thick) (highlighted in red)
• 6x Magnets (3mm dia x 2mm thick) (highlighted in red)

Assembly process

1. STEP 3a: Install the Suspension Lug to the Side Case Segment (Top) using 4x M3-12-Cap Screws
2. STEP 3b: Install the 1st Front&Rear Polar Cap to the “Physics Package” from STEP 2 using 6x M3-12-Cap Screws. Please note: The centre screw must go through the centre hole of a Pentagon block and the other 5x screw through the centre holes of the associated 5x Hexagon blocks
3. STEP 3c: Glue 6x Magnets (5mm dia x 3mm thick) to the magnet holes on the Forward Cone
4. STEP 3d: Align the Forward Cone and the Side Case Segment (Top) to the sub-assembly from STEP 3b. Please note: The orientation of these parts in relation to each other must be 100% correct. The cut-out slots on the Forward Cone and Polar Cap can be used for alignment. See pics below for reference.
5. STEP 3e: Align the 4x Side Case Segments around the “Physics Package”, then secure all forward flanges together with 25x M3-12-Cap Screws and 25x M3 Nuts
6. STEP 3f: Glue 6x Magnets (5mm dia x 3mm thick) to the magnet holes on the top face of the Aft Cone, and 6x Magnets (3mm dia x 2mm thick) to the magnet holes on the side of the cone
7. STEP 3g: Align the 2nd Front&Rear Polar Cap and the Aft Cone to the sub-assembly from STEP 3e. Please note: The orientation of these parts in relation to each other must be 100% correct. The cut-out slots on the Aft Cone and Polar Cap can be used for alignment. See pics below for reference.
8. STEP 3h: First, secure the 2nd Front&Rear Polar Cap to the “Physics Package” using 6x M3-12-Cap Screws (similar to STEP 3b). Then, secure all aft flanges together with 25x M3-12-Cap Screws and 25x M3 Nuts

At this STEP, if you want the model to look more realistic, use some cables and connect one end of each cable to the 12x screws located at the Front&Rear Polar Caps. Each screw represents a detonator, and the cables represent the wires that carry electric current from the “X-Unit” to all 32x detonators – see How-to video on top of the page for more detail

Parts required (refer to the photos below)

• 1x A Plate&Batteries (a)
• 1x X-Unit (b)
• 1x Barotube Manifold (c)
• 1x C Plate (d)
• 1x Stand (Core) (e) (Optional)
• 1x Inner Case Assembly from STEP 3 (f)
• 20x M3-12-Cap Screw (g)
• 20x Magnets (5mm dia x 3mm thick) (highlighted in red)
• 6x Magnets (3mm dia x 2mm thick) (highlighted in red)

Assembly process

1. STEP 4a: Install 20x M3-12-Cap Screws to all the Side Case Segments of the Inner Case Assembly from STEP 3. Please note: All the holes on each Side Case Segment should align perfectly with the holes on each Outer Explosive Blocks from the “Physics Package”. If they are not, check parts alignment in STEP 3 to ensure all parts were oriented correctly in relation to each other.
2. STEP 4b: Glue 2x Magnets (5mm dia x 3mm thick) to the magnet holes at the back of A Plate&Batteries
3. STEP 4c: Glue 12x Magnets (5mm dia x 3mm thick) to the magnet holes on the X-Unit
4. STEP 4d: Glue 6x Magnets (3mm dia x 2mm thick) to the magnet holes on the inside of the Barotube Manifold
5. STEP 4e: Glue 6x Magnets (5mm dia x 3mm thick) to the magnet holes on the C Plate
6. STEP 4f: Assemble all parts to the Inner Case Assembly from STEP 3.
7. STEP 4g (Optional): If you want to display the Inner Case Assembly after this step, place the model on the Stand (Core)

Similar to STEP 3, if you want the model to look more realistic, use some cables and connect one end of each cable to the 20x screws located all around the Side Case Segments. Each screw represent a detonator, and the cables represent the wires that carry electric current from the “X-Unit” to all 32x detonators – see How-to video on top of the page for more detail

Parts required (refer to the photos below)

• 1x Nose Cap (a)
• 1x Forward Case (b)
• 1x Rearward Case (c)
• 4x Self-Destruct Fuse (d)
• 8x Brass Solid Round Rod 2mm Diameter 100mm Length (e)
• 1x Inner Case Assembly from STEP 4 (f)
• 32x Magnets (5mm dia x 3mm thick) (highlighted in red)
• 10x Magnets (3mm dia x 2mm thick) (highlighted in red)

Assembly process

1. STEP 5a: Bend and cut the Brass Solid Round Rods into correct shape/length – see pic below for reference. You’ll need 4x sets of Antenna made out of these rods
2. STEP 5b: Glue 3x Magnets (5mm dia x 3mm thick) to the magnet holes at the back of the Nose Cap
3. STEP 5c: Glue 17x Magnets (5mm dia x 3mm thick) to the magnet holes at the front and rear of the Forward Case – see pic below for reference. Glue 10x Magnets (5mm dia x 3mm thick) in 5 stacks of 2 each to the magnet holes on the top face of the Forward Case.
4. STEP 5d: Install the 4x Self-Destruct Fuses, and 4x sets of Antenna to the Forward Case
5. STEP 5e: Glue 12x Magnets (5mm dia x 3mm thick) to the magnet holes at the front and rear of the Rearward Case – see pic below for reference
6. STEP 5f: Assemble the Nose Cap, Forward Case, and Rearward Case to the Inner Case Assembly from STEP 4

Parts required (refer to the photos below)

• 1x Tail Assembly (a)
• 1x E Plate (b)
• 1x Outer Case Assembly from STEP 5 (c)
• 12x Magnets (5mm dia x 3mm thick) (highlighted in red)

Assembly process

1. STEP 6a: Glue 8x Magnets (5mm dia x 3mm thick) to the magnet holes at the front and rear of the Tail Assembly – see pic below for reference
2. STEP 6b: Glue 4x Magnets (5mm dia x 3mm thick) to the magnet holes on the “E” Plate
3. STEP 6c: Assemble the Tail Assembly and “E” Plate to the Outer Case Assembly from STEP 5

Parts required (refer to the photos below)

• 1x Oppenheimer_Full Body
• 1x Oppenheimer_Hat
• 1x Main Stand
• 1x Atomic Bomb from STEP 6

Assembly process

1. STEP 7: Place the Atomic Bomb on the Main Stand, place a 1:10 scale Oppenheimer figure next to the Atomic Bomb

Congratulations, you have fully built the 1:10 scale Atomic Bomb model at this point!