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knife case

Hobby Knife Case

I sometimes do hobby crafts. Often the projects involve a sharp hobby knife. The brand I've typically used is X-ACTO and, most often, the basic version. The price is right, but the knife typically comes in plastic/cardboard "bubble" packaging. After opening the package and cautiously removing the sharp knife, I'm hesitant to put it down. The knife rolls easily.


Some versions do come with a slide-off plastic cap, but, as you can see in the illustration photo, not always. So, when I bought a new one recently I didn't want to just drop into my hobby tool drawer. I am averse to cutting myself. This case is my solution. I can quickly grab it from the drawer and carry it safely to the work table. It has space for extra blades, too. The case closes tightly and there's an intentional gap on the side to let me grab the knife by the handle without tipping the case.

The design of both the base and top modules is a cube from which the space for the knife and extra blades are removed with difference(). The same is true of the top, but the catch for holding the top closed is added to it.


Unfortunately, my printer is "just" too small to print the hinged cover of the box straight across, so I need to print the top and the base separately. For me, each part gets rotated to fit diagonally on the printer. However, the OpenSCAD program code does allow you to print both at the same time if you have print dimensions big enough.

if (part==1) base();
if (part==2) {rotate([0,0,45]) top2();}
if (part==3) {

The case hinge is a piece of wire cut from a metal coat hanger which seem to be almost too easy to get. I bent one end of the wire 90 degrees before sliding it into the holes through both top and base. Then I carefully bent a the other end of the wire and snipped it short.

Available Files:

(In most browsers, right click each file you wish to download and select "save-as" from the menu options.)

SCAD files for study/modification and STL files for quick prints

knifecase01.scad - knifecase01base.stl - knifecase01top.stl appx. 2hr to print both parts on Lulzbot Mini
GPL3 License