Razor blade scraper for getting under prints. Adds locking tabs to the original model, as part of the holder body and on a slide-in clip that engages the outside notches on a double ended razor blade to retain the blade so that it doesn't come loose when you pull back to recover. Includes slip cover for safety when not in use. UPDATE: I have a redrawn version with a better blade retention mechanism here: http://www.thingiverse.com/thing:697672 Give it a try if you want to make sure the blade never slips out.Print holder, cover, and retainer; other STL files are to show assembly. Print holder at 0.15mm layer height and 0.40mm extrusion width if possible. The retention clip is small and may ooze from insufficient cooling. If it seems too big to fit in the slot, you may need to take a file to it. As in the source model, there is a single track of filament on the side of the holder where you slide in the blade to provide a bridging point for the blade slot which you will need to break. A sharp knife and some twisting works well. Slide the razor in from the side and push it all the way across, making sure it engages the retention tab in the body. Then insert the clip with the outer portion on top of the holder. The slip cover should fit with the clip in place.