PETG Channel joint Cap Design

I need a simple yet precise 3D model of an joint cap that will slide neatly into an aluminum channel for a personal DIY build. The cap will be printed in PETG, so the geometry must respect typical wall-thickness and shrinkage characteristics for that filament.

I will share a hand-sketched technical drawing with exact measurements, tolerances and the channel profile the cap must fit. From that reference, I’m expecting a clean, watertight CAD model and a ready-to-print STL. A STEP or native file from Fusion 360, SolidWorks, or similar would be useful for future tweaks. I will also provide a .stl of a current cap that has been testing for fitment.

Deliverables
• Final STL optimized for PETG
• Source CAD file (STEP or native)
• One quick note on recommended layer height and infill so I can duplicate your results on my printer

Accuracy at the mating faces is key—if it snaps in without wobble, we’re done.