Introduction: Toddler Ghostbusters Costume

About: Father of 5 kids, been doing crafts and costumes for a few years now. I had a little break for a while but back in the fold again now. I'm an engineering Technician by trade and love to create.

Hi all, great to be back here once again. I've had a little bit of a break due to family life but back with a vengeance with a Full Toddlers Ghostbusters Costume. Everything has been designed and created by myself except for a few pieces I modified that existed on the web. In these I will make reference the originals during the build.

So this is an instructable for a toddler size costume. The toddler in question is my daughter. She is 2 yrs old but has a genetic issue which causes her to not grow as normal so in the real world she's the size of a 9-12 month standing baby. So please bare this in mind if you are recreating this instructable and resize all parts accordingly. I will include actual dimensions to everything.

**** Edit two Costumes where actually made see Notes at the end of the Build. Thank you !!!!




Toddler Boiler Suit £9.99 - 1-2 yrs Boiler Suit Amazon ( This I had to get tailored to fit my daughter as its the smallest one I could find).

Beige Dye for Boiler Suit £7.00 - Beige Dye Amazon

Proton Pack Construction

Cardboard - Free from most Shops in the form of boxes

Clear plastic tubs - Free from fruit containers

Tubing £5.99 - 10mm Corrugated Conduit Pipe Amazon

Foam Mats pack £10 - Pack of 9 Foam Mats Argos

Thin Foam Sheets - £6.06 - Pack of 20 Sheets Amazon

2 x Sound Recorder and play module boards £4.58 - Sound Voice Recording Playback module Amazon

Custom 3D Printed Parts

Backpack straps - Free taken from an old backpack.

Neutrino Gun Construction

Clear Tubing £2.74 - 12mm ID x 15mm 1 Metre CLlear flexible Tubing Amazon

Custom 3D Printed Shell

Plastic Tubing £1 - Taken from a kids hula hoop

Wires for Decoration Free - Taken from old electronics

Circuit Board Construction and Circuit Parts -

1 * Ferric chloride pack 100g - £3.99 - Ferric Chloride Amazon

8 Wire Multicoloured cabling - £6.49 - 8 Wire Cabling Amazon

Bought From Kitronik

1 * Copper Board 10cm * 16cm - £2.52

4 * Red LEDs - £0.60 (Pack of 10)

3 * Blue LEDs - £1.15 (Pack of 4)

2 * Amber LEDs - £0.60 (Pack of 10)

1 * Clear LED - £1.20 (Pack of 10)

1 * Blue Flashing LED - £1.08 (Pack of 10)

NE555 Timer - £0.24

Decade counter - £0.38

Quad 2 input And Gate - £3.36 ( Pack of 10)

100R Resistors - £0.82 (Pack of 100)

220R Resistors - £0.82 (Pack of 100)

1K Resistors - £0.82 (Pack of 100)

68K Resistors - £0.82 (Pack of 100)

330R Resistors - £0.82 (Pack of 100)

4.7uf Capacitor - £1.08 (Pack of 25)

2 * Mini Toggle Switches - £1.63

2 Way Low Profile Terminal Block - £2.52 (Pack of 25)

Jumper Wires 20cm Long - £3.00 ( Pack of 40)

Bought from Ebay

2 * Blue Bargraph LEDs - £4.74 ( Pack of 10)

1 * Yellow Bargraph LED - £4.74 ( Pack of 10)

1 * Push button mini switch - £1.99 ( Pack of 10)



3D Printer

Crafting/ Cutting Mat - ( Not necessary )

Stanley Blades


Glue Gun

Soldering Iron and Solder

Needle & Red Thread


**Optional: 1kg Polymorph Plastic Beads £19.99 - Thermoplastic Beads Amazon ( These I had lying around and used them to hand make some custom parts and create a plastic shell to cover some foam parts. Is not needed)

**Optional: 1kg 3D Print Filament £16.49 - SUNLU 3D Printer Filament PLA Plus Amazon ( This is only if you have no 3D filament left which was what happened in my case. Only *%*kg of filament is required)

Step 1: Step 1: Initial Measurements and Templates

Info To know:

There is a great site that provides a lot of detail in the specifications for almost each part to the proton pack. That is this Ghostbusters dimensions

From this I Used this overall template to get a general layout of what I needed and where to position it.


  • Download the template to your PC.
  • Bring up the template image on any image manipulation tool. ( A great free one is called Gimp).
  • As this is full Size you may need to resize this depending on the size of the wearer (I resized the image to fit my daughters back dimensions of 17cm across the shoulders and 27cm in length to the bottom of the back and will be using these dimensions throughout this instructable).
  • Try and keep the size as uniform as possible when resizing. I couldn't due to the back dimensions so needed to add more on to the bottom of the costume to make the bottom disc more circular. I can explain this in more details later.
  • Glue the finished paper template onto a strong card backing( I used a corrugated card box used in transport of fruit) and cut to match the template shape.
  • Do Not make the Back plate or the additional sides underneath to house the electronics just yet. ( I did and it was a mistake as I had to enlarge the cyclotron first)
  • Next measure each individual part from the template and estimate the height you would need for each of these to be 3D Printed. ( Printed parts are highlighted in Red on the Proton Image)
  • In the other Proton Pack image I have labelled the main parts and will use this to reference the parts in the build.

These were my Dimensions for the Main Parts of the Proton Pack. All dimensions are in mm in the form of L * W * H, unless otherwise stated.

  • Motherboard : 300 * 170 * 30
  • Cyclotron Disc Diameter : 140
  • Synchronous Generator : 220 * 180 * 20
  • Booster Diameter : 35
  • HGA Diameter : 25
  • Crank Generator : 57 * 27 * 30
  • Vacuum pump : 39 * 14 * 14
  • Gearbox : 57 * 27 * 30
  • Power Cell : 58 * 25 * 40
  • Iron Arm : 30 * 25 * 65 ( Base is Slopped and width changes to 10 a 1/3 of the way up)
  • Frame : 65 * 40 * 6
  • Gun Mount & Bridge : 45 * 23 * 30 & 39 * 12 * 21
  • Attenuator : 45 * 35 * 34 & Cylinder Cut with a Diameter of 17 on top Right Side
  • Cyclotron Disc LED Containers (4) Diameter : 25 & Height of 20
  • Cyclotron Disc LED Caps (4) Diameter : 35 & Height of 4

Step 2: Step 2: Cut Out the Required Foam Parts

Next Step is to Create the Foam Parts to be attached to the Cardboard base of Motherboard.

See Image schematic with highlighted areas of what is created in Foam, it is basically the Synchronous generator , cyclotron and cyclotron band that is created out of foam. ( I also bulked up the base of the Iron arm using Foam underneath).

To create the Synchronous Generator print out a duplicate of the proton pack layout and cut out the Synchronous Generator part and overlay onto some of the foam. Before you cut this have a look at the cyclotron shape is it round and symmetrical? ( Mine wasn't after resizing for my little girl)

If it isnt then measure the widest part of the cyclotron diameter and on a separate piece of paper or card re-draw the cyclotron using a pencil and compass and half of the diameter measured. Cut this out and stick to the synchronous generator cut-out at the best fit as possible.

Now with your new template cut out 2 foam pieces of the required shape and hot glue them together.

Measure the thickness of the combined foam cutout and cut out this thickness in long strips from thin foam sheets. Hot glue this to the edge of your cutout to hide the join.

Now the Cyclotron, this is basically 3 disks from foam.

The Bottom Disk is 20mm shorter in diameter from your Cyclotron disc you created earlier..

The top is 20mm smaller than the bottom disk and this time you'll need two of them. Hot glue these together like before. If you are not using the polymorphic plastic beads then finish using thin foam glued to the edges like before.

Step 3: Step 3: 3D Printing Parts

Because of the costumes size I realised I could easily 3D print a lot of unique parts in this build rather than the usual create out of foam and patch method I'm used to doing. I'm also relatively new to the whole 3D printing process so I apologise in advance for any mistakes.

I used Tinkercad to create these parts it is free and easy to use. All parts are created from basic shapes then grouped together to create each object. Each object can then be selected and exported individually.

They were created using the dimensions mentioned in Step 2.

All parts are printed once except for the LED Casing and Top . These where duplicated until there were 4 pieces before printing.

The printing software used was Cura again a free software and it works well for me. But you can use any software you wish to print these parts.

There is no guide really here to go through.

  • Download the stl 3D parts
  • Resize if needed on your printer software or upload and resize using Tinkercad
  • Print Parts and wait

Step 4: Step 4: Putting It All Together

This is the real start of the build.

Now when you have all your 3D printed and foam parts you just need to gather up a few extra resources. These are needed for the tubing and wires to attach to on top of the synchronous generator and all Pipes.

First to create the Pipes which are the HGA, N Filter & Booster you can use carboard tubes. Both the Booster and the N Filter are made from the same Tube. (The tube I uses was an old poster storage tube, but you can use any Tube that has the required thickness. I think large Kitchen roll tubes have the correct thickness. It doesn't need to be strong as it wont be supporting anything of note)

The booster is cut to 110mm length and the N Filter cut to 60mm Length.

HGA Tube is cut from a Childs play bubbles container to the length of 33mm. (A toilet roll tube would also work)

Injectors next, there are two of these which should be glued together and inserted into the Power cell Part. These are 18mm in diameter and 77mm in length. ( the issue with this is that there aren't many tubing's available at 18mm diameter. So if you need too use a smaller tubing and hot glue around the openings of the power cell to conceal any gaps before painting - I ended up using a child's hula hoop which was the perfect dimensions but took a little while to straighten out)

For all the other Tubes that protrude out from the motherboard , there's 4 in total and I find the best thing to use is the plastic containers of the candy lipsticks. These look great when painted.

Hot Glue everything except the cyclotron pieces into position on the template and glue the flexible tubing from the vacuum pump to the first casing down , see images for better explanation.

Make a hole through to the other side roughly where you're going to put the N Filter, this is for the LED leads to feed to the main board below.

Lastly Spray everything black.

Step 5: Step 5 : Installing the LEDs

Take 4 red LEDs and 8 pieces of electrical cable each a different colour ( The different colours are to determine which is positive and which is negative and also which goes to what LED number..... Simples no? or you could label each end with a small sticker).

Solder one 100Ohm resistor to the positive leg of each LED.

Solder two wires to each of the LEDs . One on the positive resistor terminal and one on the negative - take note which is which.

Take the an LED Base and hot glue one LED inside feeding the wires out the exit hole in the side. Repeat for each base.

Make a hole in the side of the N-filter and feed all 8 wires through the hole then through the hole in the synchronous generator that was made earlier to the back of the template.

Take the bottom cyclotron and position the 4 LED bases where you want them to be.

Using a marker draw around the LED bases onto the bottom cyclotron.

Also position the N-Filter on the bottom right hand of the synchronous generator so that half or more of the filter will be overlapping the cyclotron and over the hole made earlier. Draw around the bits that overlap with the cyclotron.

Then cut these shapes out. You can now hot glue this into place.

Repeat this for the top cyclotron piece.

Hot glue the LED bases into the bottom and cut out a small track for the wires to run to the N-Filter without obstruction. Place the wires in and Hot glue the N-Filter into place.

Now push the top piece of the cyclotron over the LEDS and the N-Filter and hot glue down. It should sit nice and snug and will seal the wiring from sight underneath.

****Extra Step ***** If using the polymorphic beads now is the time to melt them and roll out flat to an area one and a half times the size of the cyclotron. Shape this over the cyclotron and leave to harden. Remove and spray black when complete.

Take the LED Tops and cut out a small piece of clear plastic ( I used fruit containers ) in the same shape as the top and hot glue underneath. Hot glue these then on top of the cyclotron over each LED.

With a permanent Red marker colour each one in red.

Finally install the 2 blue bargraphs to the power-cell. Wire 10 differenct colour wires to these. One wire to two positive pins in sequence from bottom to top.

Feed the 10 wires through a red wire sheath and out one of the injectors into the left side of the proton pack cyclotron.

Solder all negative pins together and fed out through a negative ground wire and out the other injector into the left side of the proton pack cyclotron.

Hot glue the bargraphs in place and glue on the top cover with clear plastic sheet underneath.

Step 6: Step 6: the Neutron Wand

**** Note *****

This was mostly created from a 3D print file.

I modified an existing file on the Web to meet the needs of a working neutron gun. Here is a link to the original file Original neutron files.


(It saved me a lot of time in the design phase, so all I did was take the object file of the main body and modified it so the inside was hollow enough to place the LEDs and electronics and hollowed out the switch and LED positions. From this I create my 3D file attached here)

For the input and output pipes use the plastic hula hoop cut to 125mm Lengths and straightened.

Inserted these into the front and rear entries of the neutron husk and glue in place.

On the front end pipe hot glue a flashing blue LED with attached positive and negative wires about an inch below the visible edge. Then cut a 2 inch piece of plastic clear tubing and hot glue that to the end of the pipe.

Next put a cap on top of the clear plastic tubing to finish the front of the gun.

**** Extra **** - The cap I made is from the polymorphic beads but can be made from foam.

Using the foam boards cut out two 110mm * 25mm pieces.

Get a 5 pence piece of a small disk of 18mm diameter and with half of it over the top edge of the foam draw around it to make a semi circle. Move the 5 pence over just slightly more than the 18mm and repeat 3 times.

Cut out what you have stencilled and you now have grips for each end of the neutrino wand.

**** Extra **** - Polymorphic beads can be used to cover the grips.

Next cut out some flexible plastic tubing. Enough to reach from the bottom of the proton pack to the top in a nice arc shape with some extra wiggle room so it hangs loose.

Glue one end of the flexible tubing to the rear tubing of the neutrino wand and secure with electrical tape.

Install the switches - ( two toggle switches on the face one above the other and one push switch on the left)

On the Ledge below the toggle switches put in an amber LED

On top put in a white LED and under the Vents at the top glue in 3 Blue LEDs in parallel with a 230ohm resistor.

Finally at the front install another Amber LED.

Connect all LEDs with positive and Negative wiring each with a 230ohm resistor on the positive leg.

Next cut 7 Wires preferably of different colours and feed them through the flexible tubing onto the rear of the neutrino.

1 - wire is in to switch one.

2 - wire is out from switch one.

3 - wire in to switch two.

4 - wire out from switch two.

5 - wire in to push switch.

6 - wire out from push switch.

7 - Ground Wire out to main board.

Attach each wire as mentioned above except for the ground wire.

For each of the positive wires from the normal LEDs attach to the output on switch two.

Solder the positive wire from the blue flashing LED to the push button switch.

Solder all the negative pins together on a piece of circuit board and then solder the ground wire out the main board to this also.

Then take the Yellow LED bargraph and solder 10 different colour wires to each of the positive pins.

Solder all the negative pins together and attach to a ground wire.

Feed these back down the flexible tubing towards the main board and hot glue the bargraph to the vent at the right of the toggle switches.

Glue the other end of the Tubing to the right of the cyclotron on the proton pack.

Finally cut out a thin metal piece the same size as the opening at the bottom of the neutrino husk and glue in place. To remove any sharp edges hot glue all the way around the metal cover.

( The bottom is metal as small magnets will be used to hold the neutrino wand onto the side of the proton pack)

Step 7: Step 7 : the Main Board

**** Note ****

I created the final circuit design using software called circuit wizard. This is a paid software that I've had for a while now. But I have included the schematic files here to be used. The initial Design was done using tinkercad again my one stop shop for everything. I also used this to create the Arduino code that will run the bargraphs.

***Also there is a slight error on the board schematic. When I designed it I left positive nodes to help power the Arduino and sound boards etc. In my haste I put these before the main switch so if connected they will always draw power. To eliminate this issue make sure all power connections are after switch one.


So how the circuit works is the power comes into the board from switch one.

Then from here it sends power to a 555 timer chip which creates a pulse. This in turn goes into a Johnsons decade counter chip that creates a cycling power on and off swapping between pins until the reset is called at pin5. This creates the 4 cycling LEDS on the cyclotron.

Power is also fed to pin 10 of the Arduino which then runs the pins 0 to 9 in a sequential scale up and back again this is fed to the pins on the bargraphs attached to the proton pack.

Power is fed to sound board with pre-recorded noise of proton pack turning on.

Power is also supplied to switch 2.

When Switch 2 is turned on the normal LEDs on the neutrino wand all light up.

Power is returned to part 2 of the board which then feds into the 4 and gates along with the power from the arduino cycling which then in turn lights the yellow bargraph on the neutrino wand in a scale up and down motion.

Power is fed to push switch.

When push switch is pressed the blue LED will flash

Power is returned to part 3 of the board which in turn sends power to the other sound board that makes the neutrino wand sound while its active.

Creating the Circuit Board

To create the board take the copper circuit board plate scuff the best you can with sandpaper and wire wool, wash then dry the board.

Next print out the circuit schematic on photo paper with a laser printer. ( I had to use the one at my work)

Overlay the print on top of the copper - Ink side down and cover with greaseproof paper

Next using an Iron apply heat and pressure on top of the board for a few minutes trying to be as evenly as possible.

Remove the paper and scrub the copper plate gently with a scouring pad and wash with soapy water.

Check the transferred print with a mock image. If there are any gaps that didn't transfer fill them in with a permanent marker pen.

Prepare your acid bath by mixing the ferric chloride with warm water and activate it by stirring with a plastic fork or stirrer, place copper board into the bath and wait. ( Always wear rubber gloves while handling this)

Once all copper has been etched away use an ink remover ( I used nail polish remover) to remove the ink leaving the nice copper tracks.

Using a small circuit board drill bit drill all holes that are required by the board.

Next follow the schematics included to solder all parts into their correct place.

Dont forget to include the external wire connections needed on the face of the circuit board as shown in the images.

Connect all wires from both the proton pack and neutrino gun to the main board.

Connect a power wire and a ground wire to the Arduino.

Step 8: Step 8 : Final Touches

Create the housing for the electronics. This is done by cutting out 30mm strip of corrugated cardboard and glueing it along the edges of the proton pack. this was then in turn covered with the thin foam sheets cut to the same size.

Make the backing plate from the same cardboard using the proton pack as a stencil.

Glue on a foam backing to this to protect the young wearer.

Next cut out two slits at the top to feed the backpack straps through.

Feed straps through slits and attach to the underside of the proton packs rear.

Cut out a small opening at the op of the pack the size of a 9volt battery. This will be used to power the board.

Glue the backing to the proton pack.

Glue on the extra 3D printed parts.

On the proton pack it is similar paint the required areas silver.

Attach the multi-coloured ribbon cable

Attach the red and blue wires.

Create the Cyclotron Band from foam and spray it black. This is done to measure based on the height of the Cyclotron. Hot glue into place.

Print out the Proton Pack Stickers to your required size , cut and glue onto the areas needed on the pack.

Attach the mini magnets to the right hand side of the Gun Mount.( I used 6 of these )

Final touches on the neutrino gun is painting the required areas in a silver colour.

Take the overalls costume shorten it up to as close as the child's size as possible.

Then Dye to a dark beige colour.

Finally using the Font included print out the name of the child onto a sheet of paper.

Glue this onto a black piece of material or foam ( I used thin foam worked great)

Then using a needle and red thread go around the letters until completely covered and remove the paper when complete.

Attach to the Childs costume.


End Notes :

This was an enormous amount of work that I didn't realise once I started. It was challenging but rewarding.

Near the end I realised my wee woman wouldn't wear this as she has a fear of noise in things and stuff pulling on her.

When we tried to get her to wear a backpack she freaked out a bit. But half way through the project I noticed that she copied everything her big sister did ( she's 7) including trying to put on her bag to go to school herself. So the decision was made to make 2 Costumes.

So like I said about half way through I adjusted the dimensions and build a second proton pack at the same time that was almost identical except for the 3D printed parts. For those all I did was 3D print the top to make it look like the entire part was printed and made the bottom parts out of foam and use Velcro to attach the neutrino Gun to the side of proton pack.

Everything else was the same.

And you may notice on the final video that the bigger sister is recorded first. This was because as we thought the wee woman wouldn't wear the costume but the instant her bigger sister has it on she had to get hers on too. So in the end it was a great result.

Halloween Contest 2019

Second Prize in the
Halloween Contest 2019