House M.D. Oversized Tennis Ball





Introduction: House M.D. Oversized Tennis Ball

About: Hi, my name is Britt Michelsen, I'm a Chemical Engineer especially interested in Computational Fluid Dynamics. To balance all the theoretical work I like to make stuff in my free time.

All over the web House M.D. fans rack their brains on where to find the mysterious over sized tennis ball also known as BOUO from the TV show.
It can be bought in the official store with a big logo on it, but I wanted to have one that looks exactly like the one on the show. So after a long time of searching through pet stores, I thought of a way how to make it myself.

Btw if you know where to find or how to make the grey saucer, please tell me.

Step 1: What You Need

  • red and grey wool roving
  • white Casein paint
  • Styrofoam Ball (the diameter depends a bit on your taste, it grows notably between the first and the second season, mine is 12 cm)
  • olive oil soap
  • white vinegar
  • lighter
  • Felting Needle (If you are not that familiar with felting get more than one because they break very easy)
  • small paint brush

Step 2: Trace the Template

I've attached the template for a ball with a diameter of 12 cm. Simply scale it so that it will fit yours.

Make a stencil out of aluminium foil or anything, that you can place on the ball and trace the outline. Then use a ruler in order to trace the other line.

Step 3: Needle Felting

Grab a little bit of your roving, place a thin but covering layer on the Styrofoam ball and jab it in with your felting needle, starting with the outline. Make sure, that the area is completely covered, else simply add more wool to cover up any open spaces. You will have to jab many, many times into the ball.
When you are happy with your first side, do the same for the second side.

If the small holes don't bother you (or you are just lazy ;-)) simply skip the next step.

Step 4: Wet Felting

This is probably not a very professional way on how to wet felt, but it worked pretty good for me...

First prepare a bowl of hot water (make sure not to burn yourself) and add olive oil soap (about a table spoon per litre). Then dip your hand into it and carefully massage your ball with circling movements. Start with the outline and then move to the middle. After a time you can use more pressure.

When you are happy with your result, prepare a bath of cold water and white vinegar and put your ball into it. Carefully move it around and let it dry afterwards.

I've used a lighter to carefully smooth the surface. But be very careful not to burn any holes into the wool or the ball. You should better do this outside, because it smells pretty bad.

Step 5: Paint the Line

In order to paint the line you should use Casein paint, it can be used for Styrofoam and is waterproof. Your paint brush should be the same size as your line. Simply paint all around the ball.

Congratulation, you are done!



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You could get some carpet tiles and make an even bigger one using them

My husband found a square dish that looks just like the thing House uses to hold this ball on the show. He found it at IKEA a few years ago, but I couldn't find it on the website, so they might not make it anymore. I think it's supposed to be a candle holder (that's what I use it for), but it could also be a soap dish.

or you could just buy one on ebay. Search for House MD ball. There's one without any markings on it.

Whoa,   are "House" watchers finally coming out of the closet?   I love the show.  I just wish I didn't work such a weird shift so that I have to catch things on the weekend or during "marathon days".

The ball of unknown origin is great,  thanks.

Hey, cool!!! Just a question, where are you from? I noticed your vinegar's bottle label is in spanish.

2 replies

I'm from Germany. It is hard to see in the picture.. actually it says "bianco" which is italian, the spanish word is blanco. I bought it in our local supermarket... I speek spanish though because I lived a year in Chile.

oh!, I do know the spanish is "Blanco" since I live in Colombia so when I saw the bottle I just assumed it was "Blanco", anyway thank you so much for this instructable.

That exact ball is sitting in my dog's toy bin.  We got it at PetSmart I believe (or maybe Petco).  They have all red, all purple, pink/yellow, orange/teal, and red/gray.  I seem to recall it costs around $4.00.

Your Views Count is an amazing idea. I wanted to post this Instructable a week earlier, to make sure that I get the 50k view. Glad it worked out anyway.

I took me some time to figure out what paint to use. In the beginning I wanted to use Lexan Paint, but I found out that there is actually only one thing that it likes to stick to.... itself.

I'm confused by your instruction to use casein.  I'm a painter, so I'm familiar with casein, but I wouldn't expect most people to know what it is or where to get it.  I assume acrylic (cheaper and easier to find) will do the job just as well?

I tried Acrylic Paint, but because at least the paint I used (I tried two different types) was thinner than the Casein Paint I needed many layers and the end result didn't look as good as the Casein Paint. In case somebody is wondering where to get it I used Plaka Paint from Pelikan.

I didn't know what you were talking about... then I found this image... but when I try to attach it... it gets corrupted so here is the link.


 It doesn't bounce though....

I want 1 that bounces...

2 replies

Similar to the comment  BrittLiv mentions above: Peel the felt off of the syrofoam and glue it to a rubber playground ball of the same size. 

It bounces better than you might think, I was surprised myself.

Great instructable!  I can't wait to make one for myself.

wow this is so cool! how big can you make them?

1 reply

thanks, you can make them as big as you want, you just need to find a Styrofoam ball in the size.

I don't watch House, so I don't know what a BOUO ball is for.