UPDATE: I'm surprised people are still liking and collecting this old, terrible, obsolete version! WHY? WHY? WHY? I have designed a new (2020), improved 3-inch wide blue painter's tape dispenser. It is at https://www.thingiverse.com/thing:4110302 and it is much better -- better assembly method, more rigid, non-gravity dependent hub, no glue, better blade, better overall design.
My original dispenser (the one on this page) has turned out to be fairly popular, but it is not very rigid, and has other issues that make it less friendly, however, mine has been in use since 2013, so it has stood the test of time quite well. But it's not nearly as spiffy as my new (2020) design, so check it out at the above link before you consider printing this old crumby one.
Tape dispenser for 3-inch wide blue painter's tape. Improved Dec 24, 2013. Fully 3D printable without supports.
New (2014) improved version has base parts with holes for mounting screws and they clip over the bottom of the side parts (one near the front, one near the back) for sturdy mounting to a bench. The first photo shows the original version that had base parts with no holes (I drilled them to put screws through to the work bench) and relied on glue to bond them to the sides, but the force required to pull tape off the spool was too much and the glue joints kept failing. This revision fixes that by having the bases clamp over the horizontal members at the bottom of the sides. The blade still uses super glue to hold it in place -- more about the blade in the instructions.
A printable serrated blade can be found at https://www.thingiverse.com/thing:2329277
Second photo added 13MAR2014 showing the new bases that clamp over the bottom of the sides.