UPDATE: version 2 can be found here: http://www.thingiverse.com/thing:1015046

Razor scraper for removing tough prints. Uses commonly found utility style blades. I've included both a single color .STL file and a dual color .thing file. There's a slit in the middle of the handle where you insert the blade. Enjoy!

Printed mine with these settings:

50% infill
3 walls
.30 layer height
No supports or rafts

So far so good..

I dont know the screw size but I'm sure anything that fits will do. The hole is drawn at 3mm, but they always print smaller.

I cleaned out the middle where the blade goes with the same blade and thin hobby screwdriver.