The Ultimate Optimus Prime Costume Tutorial

Tutorial for Kids Ultimate Optimus Prime Costume

This tutorial will teach you how to turn a standard cardboard box into the ultimate Optimus Prime Costume. Transformers are ever so popular, and you will be surprised how easy it is to create your ultimate Autobot.

If your child is a Bumblebee fan, check out this easy Bumblebee tutorial.

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COSTUME BODY PREPARATION

In order to create your Optimus Prime, you will need to find a box to fit over your child’s head for the body of the costume. The sizing of the box is important and must be tailored to your child’s size. The box should be large enough to easily put his arms through the armholes, but too much width will make it uncomfortable to wear.

Similarly, a square box would produce too much girth and make it difficult to keep the costume in place. I recommend starting by measuring your child from shoulder to shoulder and add about 2 inches per side. So if your child measures 15 inches shoulder to shoulder. You would have 15+2+2= 21 inches for your approximate box width.

Box height should be measured from just above the shoulders to just above the hips. You want to make sure your little man can freely move his legs without the box getting in the way. So an example measurement maybe 15 inches.

Kids come in all shapes and sizes! So, it’s important to make sure you select the right depth for your box. The easiest way to do this is to have your child turn sideways and see which part of his body has the most depth. (see illustration below) For my little man, his belly protrudes the most so we measured front to back in this area.

You will take your depth measurement and add 4-6” to allow for the room to get arms into the box. So if your child was 8 inches girth (depth), 8+6= 14 inches.

Now, remember your child’s measurements will be different. However, our ultimate box based on the examples above would be 15 inches tall x 21 inches wide x 14 inches deep. Now, it is unlikely you will find a box with exactly these measurements. Remember this is just a gauge to find a basic box to fit your child.

Construction of the body

Now that you have your box, you will want to cut off the bottom of the box and make sure any remaining flaps are taped shut. Use a box cutter to cut a decent size hole in the top of the box for your child’s head. You want the box to easily drop over your child’s head without falling off the shoulders.

Once your head is in place, you can better gauge where to but the holes for the arms on each side. Make sure your child can move freely and that the armholes are not too low or too high.

Next, you will need 2 small boxes to attach over the holes on the sides. I removed both the bottom of the smaller box and the side that would attach to the body. For a better range of motion, I also opened the exterior side of the arm box so that it hung as a flap.

For the lower arms, I used 2 Kleenex upright tissue boxes. I removed the bottom and tested the opening to slide over my son’s wrist. Enlarge the opening if needed. The opening will be close to the wrist in the costume while the open side is close to the elbow.

I learned from a previous costume construction that spray painting the boxes alone doesn’t always hide the print of the boxes. So, I like to get foam board and cover the exterior of all the boxes before painting. The foam board is totally optional. However, it provides a nice uniform look if you are using several box types (corrugated vs paper). If you do use the foam board make sure to adhere it with a strong glue and be aware that too much hot glue will melt the foam board.

Optimus Prime’s body including the arms will be painted red. I then cover all the seams with matching red Duct tape. You can then attach the upper arms to the body using the red duct tape. The lower arms are not attached.

Costume Details

Now it’s time to do your details!

I created a grill by taking a standard sheet of card stock and folding it several times in and out. The windows can be designed with cardstock as well.

I created the smokestacks with 2 empty paper towels rolls. Then, I created a warrior panel for the front of the costume using leftover corrugated box pieces. It should go the full width of the costume and allow for movement.
The grill, smokestacks, windows, and warrior panel will be spray painted silver. You can then use either red or silver duct tape to attach these items to the body in your desired placement.

For each wheel, use 2 black dessert plates with a piece of styrofoam sandwiched between them. You could also use leftover corrugated cardboard. You just want to have a little depth to your wheels to give an authentic look to your design. I painted a white pinstripe on the outside of each wheel and then used black duct tape to sandwich the plates together.

You can then glue the wheels onto the costume. Place 1 on each side of the body towards the back and 1 on the outside of each leg.

I found an image of the Autobot symbol online and simply printed it in color on cardstock. Then, I glued the symbol to the upper arm of the costume.

I found silver mini-flashlights at our local dollar store which were attached to the top of the body to give the impression of floodlights. Win, win! What household doesn’t need extra flashlights? I also loved that the costume had working lights especially when it’s dark outside for trick-or-treating.

Costume Legs and Helmet

This part was a bit difficult for me, and there may be better ways to create the look.
For the legs, I started with a box that I knew would fit over my son’s existing athletic shoes. You guessed it! Kleenex flat tissue boxes to the rescue. The bottom of the box should be entirely removed.

I then cut the opening of the tissue box so that my son could insert his foot but not large enough to insert his shoe. This makes sure that the boot will stay in place while walking.

I covered the sides and fronts in foam board while making them taller. (see below)

I painted the 4 smaller panels silver and the rest blue. Once dried, I pieced together the panels and reinforced both the inside and exterior seams with blue duct tape. I added a shelf on the heel of the boots and glued an empty tin can on each boot. This was to simulate the rocket boosters on some of the costume versions.

For the helmet, I used an old bike helmet as my base. I knew it would stay in place rather than attempt to paper mache a monstrosity. I cut a piece of styrofoam based on the curve of the helmet. Then, adhere the styrofoam to the helmet with glue. I used the same styrofoam to add length to the sides of the helmet, and those were glued as well.

The helmet was then spray painted blue. The styrofoam did not hold the paint well, and we ended up using blue duct tape to cover all of this. So you may choose to simply duct tape the entire piece rather than painting.

Putting it all together

Once all your pieces are created, you are ready to assemble your Optimus Prime!

My child wore black sweats under the entire costume and blue gloves to complete the look. The body will be placed on the child first. Next, you will put on the arm pieces with the smaller opening towards the wrist. The boots should be placed on the child and then his normal athletic shoes.

The smile that you will see from your child will be unbelievable. We were able to reuse this costume for school parties and just playing make-believe at home. I hope you will check out the other DIY costumes on this site for more ideas.

Happy Halloween!