My son decided he wanted to be R2D2 for Halloween and it fired up my creative streak. Here’s the finished costume:

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The costume, with inhabitant

In "Get Candy" mode.

The back
It started out with a $6 collapsible laundry hamper from Walmart. I looked at a number of photographs of R2D2 on the ‘net and used basic algebra and ratios to map out the lines on it. (If the one on screen is 3 inches across, and this line is a half inch in from the side and an inch long, and my hamper is 28 inches across then…). I used masking tape to lay out a single line then I’d trace along the edge of it with a black or blue sharpie, then peel the tape off and lay out the next line. It bled a little bit because of the weave of the nylon material, but not enough to worry about it. It was difficult to keep it all straight because the hamper is so soft and collapsible, and it’s also not square. The top is at an angle when it sits normally. I had to kind of fake it to try to make the panels not look too wonky.

One side, in progress

The other side in progress

The front, in progress
For the dome, we covered a yoga ball in plastic wrap and then covered it in paper mache. It took a lot more paper mache than I thought, but I wanted it to be sturdy. When it was dry enough to hold its shape we let the air out of the yoga ball and removed it and the plastic wrap to let the inside of the dome dry. This took a few days, even with a box fan blowing on it all the time, so make sure to give yourself enough time to get it done.

Putting on the paper mache
When it was dry I cut the bottom straight with a Dremel tool and a cutoff wheel, and then painted it with white primer.

Bottom cut flat and primer on
R2D2′s eye telescope thing was made out of styrofoam insulation. It’s cheap, sturdy and easy to cut with a knife or small saw. I mounted it with hot glue.

The foam telescope mounted with hot glue
I then spray painted the whole thing silver. Don’t make the same mistake I did: SPRAY PAINT EATS STYROFOAM. The Telescope tube thing is bumpy and textured because of the paint. I didn’t bother replacing it because it was glued on pretty solid and it didn’t look that bad from a few feet away. Still, if you do this, attach the foam bits afterwards.

The painted dome, and bumpy telescope
I used the same “ratio of screen picture to my model” method to lay out lines for the dome, then I painted it using normal craft acrylics.

The back of the dome

The front of the dome
I drilled two small holes in the top of the dome and used zip ties to attach it to the top of my son’s bike helmet. With a few adjustments it held perfectly and was easy to take on and off and was comfortable for a long period of wearing.
I cut the legs out of green styrofoam insulation, and then painted them with plain white drywall primer.

The legs partially painted
I added some pieces of wood that I got from my scraps pile to add the technical-looking bits. Note that there was a rabbet notch cut along the bottom of the styrofoam to allow them to fit together if you’re putting them on the wall, and I didn’t pay attention to that when I started decorating the legs, so one is on the inside and one on the outside. “A man on a galloping horse won’t notice” as my Mom used to say.

Legs with bits added
Some sharpie and blue paint made the legs look more recognizable:

Legs painted and decorated
I attached the legs by cutting small slits in the side of the hamper on either side of the wire spiral, cutting two holes in the foam leg, and feeding a zip tie through them both around the wire in the hamper. The top hole was through the wooden disk decoration so that was stable, but the bottom attachment lined up on plain foam. I didn’t want the zip tie to pull through the foam so I added a small bit of wood to support it.

One leg on

Support for the lower leg zip tie
You can see in the photos at the top of the post that Jennifer added two shoulder straps made out of bias tape just sewed right to the hamper.
And voila.

Done!

And from the back

Done!

Beep beep boop squeal beep whistle
If I had had more time I would have added the copper coiled pipes at the bottom of the legs, but I’m quite happy with it as it is.
It was a good costume for here, because Josh could wear a warm coat and gloves under the costume and a hat under his bike helmet. He was perfectly comfortable while we walked around. It was a bit inconvenient to get in to the car to go to trick or treat at Grandma’s house, but that’s what minvans are for, right?
See also: Making a Han Solo Blaster Pistol
Thanks BuildLounge!