Knife letter and package opener. Print flat on build plate with 0.10mm layers and 25% infill minimum. PETG, PLA, PLA+, Carbon fiber, etc. 

Only 18g of filament needed for 100% infill!

Multiple options for LH, RH, with and without teeth and textured handle.

Textured handle will print better with 0.05mm layer height, or smaller nozzle. Should also print very well on SLA printers.

Disclaimer: this model is not a weapon, and is only intended to be used as a letter opener.

A special thanks to JUSTWAY for sponsoring this project:

JUSTWAY is a company that specializes in CNC Machining, 3D Printing, Sheet Metal Forming, Injection Molding, and Urethane Casting. Whether you're looking for cheap CNC parts, bent sheet metal, 3D prints, injection molded plastic or urethane casting, JUSTWAY has you covered. I recommend it for all your manufacturing needs. 

Link: www.justway.com

Their 3D printing services offer a wide range of process options, including SLA, DLP, FDM, SLM, SLS, PJ, VC, etc. From common FDM to high-precision SLA to metal-forming SLM, whatever your needs are, you can be satisfied. They also have a wide range of materials to choose from, including metal and nylon, to meet your requirements for different materials.

The ordering process is simple and convenient, just upload the design file, select the parameters, and wait for delivery. Justway takes care of the manufacturing overseas, and the shipping. You just pay tax and duty on arrival. 

Link: www.justway.com/3d-printing