Bed frames often have these tiny little wheels that are great for positioning, but once you've found that magic spot, they dig hard into your fragile carpet. Also, if things get a little humid under there (and I ain't judgin' here...) the casters can get rusty and ruin your carpet. Print this boot four times and these feet will not only create a barrier from the casters to your carpet, but they also help distribute the weight over a larger footprint.

The casters in the image above have a diameter of 43mm and a wheel width of 15.4mm (not counting the axle, but there's room for that too.

If you found this useful, please share your work and be sure to peruse my other submissions which are almost as varied as they are many:

http://www.thingiverse.com/3E8/designs

Enjoy!