Parametric 5″ FPV Race Frame — Python CadQuery Source + STL + STEP — Print-Ready for 3D for Commercial Use

A complete parametric CAD source bundle for a 5-inch True-X FPV racing
frame. The headline isn't the frame — it's the source.

Every dimension in this design is a named Python constant at the top
of a single file. Want a 250 mm wheelbase, a 33 mm stack pattern, or
a wider beam pocket for a heavier-duty build? Change four numbers,
run "python build_frame.py", get a fresh set of STLs and STEPs in
about fifteen seconds, fully consistent with each other and with a
PASS/FAIL validation report.

This is what real parametric mechanical design looks like, and the
source is yours to read, run, modify, and learn from.

WHAT YOU GET (15 files, ~3 MB zip):

Python source (the differentiator)
• build_frame.py — heavily commented, parametric, runs end-to-end
Printable models
• 6 STL files: arm, bottom plate, top plate, camera side plate,
standoff, full-frame assembly preview
• 6 STEP files for opening in Fusion 360, FreeCAD, SolidWorks,
Onshape, etc.

Documentation
• PARAMETRIC_CAD_GUIDE.md — a working CAD reference, ~2,500 words.
Explains script architecture, every parameter, common
modifications (with code), the smooth root-to-beam ramp trick,
and the OCCT gotchas that took me weeks to learn so they take
you minutes.
• PRINT_NOTES.md — slicer settings for PA-CF and PETG, hardware
list, assembly order, troubleshooting
• ALUMINUM_STANDOFF_NOTE.txt — substitution guide for racing builds

DESIGN SPECIFICATIONS:

Wheelbase: 220 mm (True-X, 45° arms)
Motor radius from center: 110 mm
Prop size: 5.1″
Stack pattern: 30.5 × 30.5 mm
VTX patterns: both 20 × 20 and 30.5 × 30.5
Camera: 21 mm spacing, 5 tilt positions
Motor mount: dual 16 × 16 and 19 × 19 (diagonal slot system)
Total estimated weight: ~109 g in PA-CF, ~135 g in PETG

Geometry highlights: smooth lofted root-to-beam transition (no
sharp stress concentrators), lightened plates with cutouts placed
algorithmically around all keep-out zones, parametric motor pad,
full mesh validation in the script itself.

STATUS — IMPORTANT, PLEASE READ:

This is a v3.1 design that passes full dimensional validation and
mesh-quality checks. Every part is single-body and watertight.

It has NOT been flight-tested or crash-tested.

The narrowest structural web is 3.4 mm, which is on the lighter
side for PA-CF racing use. The included guide explains exactly how
to widen it if your PETG test print shows weakness.

This frame is best suited to: CAD learners who want to read a real
working parametric script, makers who want to print and tune a
frame for their own bench builds, students learning Python or
CadQuery, and FPV builders willing to test and iterate.

It is NOT a guaranteed-flightworthy off-the-shelf racing frame.
If that's what you need, buy from Armattan or ImpulseRC.

WHY PARAMETRIC?

STEP files let you edit dimensions in Fusion 360, but each edit
fights the B-rep — change one number and you often have to
recreate downstream features manually.

The Python source has none of that fragility. Every dimension
cascades automatically. Change ARM_MOTOR_END_THICKNESS from 5 to
6 and the entire frame's Z stack — bottom plate height, standoff
position, camera plate height, top plate position — recomputes
correctly without a single manual fix.

If you've never read parametric mechanical code before, the
included guide walks you through the structure so you can start
modifying within an hour.

LICENSE (read before purchase):

✓ Print as many physical frames as you want for personal flying
✓ Modify the source for your own designs and projects
✓ Use the source in tutorials, blog posts, courses, with credit
✗ Do not redistribute the source, STL, or STEP files
✗ Do not sell printed frames commercially (design is not tested
for commercial use)

Build something interesting from it? Message me — happy to discuss
attribution, cross-promotion, or a custom commercial arrangement.

Full license terms in LICENSE.txt inside the download.

REQUIREMENTS TO USE THE PYTHON SOURCE:

Python 3.10+, "pip install cadquery". The included guide covers
installation and troubleshooting. STL and STEP files require no
software — drop into your slicer or CAD program as usual.

INSTANT DOWNLOAD. NO PHYSICAL SHIPMENT.

All files delivered via Etsy auto-download after purchase.
Questions, modifications, or want a custom variant? Message me.

Personal Use link:

https://www.etsy.com/au/listing/4510037340/5-fpv-racing-drone-frame-stl-step-files