BMO Desk Mate




Introduction: BMO Desk Mate

About: Sucking at something is the first step to becoming kind of good at something

You have a magical dog for a best friend, you live in a tree house, all you need now is a BMO!

Step 1: Goals and Parts List

BMO was part of a home made present challenge issued by one of my very creative/arty sisters last Christmas. I wanted to make something cool which also had some practical uses to give it some staying power. My sister is a fan of Adventure Time like myself and a quick web search showed a heap of awesome BMO's which people have built. After shamelessly stealing some ideas I had a rough plan of how this BMO build was going to come together.


Make a BMO which looks as close as possible to the character on the show

Give it some cool tricks to help it hold onto its desk real estate (more on that further on)

Make it accessible/modifiable for repairs or alterations

Parts List

9mm MDF

3mm MDF

BMO coloured paints

Fabric for limbs

Thread for sewing limbs

Wadding for stuffing limbs

Clear Acrylic for face

Glue (used both PVA and 2 part epoxy)


Wire for limb support

Electronics for BMO guts

Paints, a sample pot of BMO aqua and various colours of spray paint

Step 2: Build a Box!

Once you know what you need to fit in your BMO, and how big he will need to be you can get started on his body. You can make a BMO body out of whatever material you like. I used MDF because it is fairly easy to work with and has a smooth finish. Using a slide compound miter saw I cut the pieces needed to assemble a BMO shaped box. The next step was to cut out the screen which would be his face. This cut out section of the face panel will end up holding the acrylic screen and the inserts which go behind it. So the screen doesn't push all the way through and into the box a backing section was stuck behind it. The backing card was still thin enough so the the screen will still end up recessed into the front of the box. When you have finished the cutting and gluing for the screen the box can be assembled. PVA glue was used to fix all the components of the box together except for the rear, which will be attached by screws in order to have access to the inside. After the box is glued together and the back panel is screwed on the edges were given a light sand to round them off and help hide the joins. Once the box was structurally assembled I drilled and cut out the holes that were needed to access the USB ports on the HUB, some holes for the speakers to operate out of, holes for the limbs to insert into and any other access ports for leads.

Step 3: Make It Look Like BMO

The Body

A sample pot of BMO's body colour was used to paint the entire box, while the inside was undercoated. The inside edges of the access holes were painted black to help them blend better and the lettering down the side was drawn on with a sharpie. Buttons cut out of some 3mm MDF were made using some reference photos off the internet and spray painted the appropriate colours. After the buttons were glued on the whole thing got a coat of clear water based varnish.

The Limbs

Using some BMO limb coloured fabric some arms and legs were cut out and sewn. To give the limbs strength the 'bones' of the limbs were made out of twisted copper wire which was wrapped with stuffing for filler. These fluffy shish kabobs got shoved into the fabric sleeves to complete the limb construction. Leaving extra length on the copper wire gave me something to fix the limbs to inside the box to stop them falling off. It took me several attempts of both the arms and legs before I had a pair of each which I was happy with because they kept coming out different sizes. If you experience the same problem don't fear, I noticed that every reject arm or leg I made increased my chances of finding a match in my 'odd limb' pile.

The Face

After a quick google image search for some BMO faces I printed off a few onto some photo paper. The Acrylic screen was used as the template to cut them to size so they would fit in behind the screen on the face panel. Behind the screen I had both the basic happy BMO face and a black of the same colour so you can draw your own face on the acrylic screen. By taking the screen out you can change between the two faces or insert any others that get made.

Step 4: Put in the Guts


This is probably where most BMO builds are going to be different depending on what components you put in as well as their individual dimensions/inputs and cables. Below is a list of what went into my BMO.

1 x 6 port USB hub (powered)

1 x 2.5" 1TB portable Hard drive

2 x Portable Pod speakers

1 x 2 way 3.5mm audio splitter

1 x Female - Female 3.5mm audio adaptor

1 x 0.5m 3.5mm audio lead

1 x 12v switch

4 x Velcro straps


For my BMO I had a powered USB hub at the base for plugging in USB powered devices like phone chargers, external hard drives, memory sticks or controllers. At the top are two pod speakers from the local electronic shop bargain bin, the type which are plugged into your phone or MP3 player instead of head phones. These speakers have their batteries charged by USB and I soldered the charging cables together so they only took up one of the USB slots on the top of the hub which were accessible from the inside of the box. A two way splitter was used to consolidate the separate pods inputs into one 3.5mm audio jack lead which can be pulled out of one of BMO's sides and plugged into audio devices. I discovered a slight hum from the speakers as they were charged from the hub and so decided to install a switch on the side of the box above the audio lead in order to isolate the speakers when they weren't in use. The remaining USB slot on the top of the hub was used to plug in the portable HDD (a 1TB 2.5" which could be powered from the USB hub). Some Velcro straps were glued onto the inside walls in order to hold everything in place and prevent all the components rattling around. Remember the more cable and parts you cram into your BMO the more legit he will look to your friends.

Step 5: Adventure Time!

When your BMO desk mate isn't making your desk more fun at home he can go out and about to transport the info on his internal hard drive or blast some tunes from your phone/mp3 player. He was heaps of fun to make and is even more fun to gift to someone. Thanks for reading!

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