Custom 3D Printed Pen Design

I have a new pen concept that I want brought to life for desktop 3-D printing in plastic. The body needs to assemble with simple clip-on / clip-off connections and house a spring-loaded 1.33-inch ball that ejects smoothly and locks back in place.

The clip system must balance strength and durability with easy, one-hand operation, and I still want the finished piece to look clean and attractive when it sits on a desk. Because the pen will ultimately be printed in plastic, please work within common FDM constraints—wall thickness, draft angles, and tolerances that keep post-processing to a minimum.

What I need from you:
• A complete CAD model of the pen and its internal spring chamber, dimensioned for a standard 1.33" ball.
• Print-ready STL files plus a STEP (or similar) master so I can tweak minor details later.
• Short notes on print orientation, layer height, and any support recommendations for best fit and finish.

I’ll test-print each iteration, give feedback on fit and function, and expect at least one refinement cycle to dial in the clip action and overall ergonomics. If that sounds straightforward, let’s get started.