Uploaded July 2025 | Updated September 2026, 2 weeks ago
🎥 Welcome to Episode 4 of the Fully Defined Build & Learn series.
Today we reverse-engineer the five-turn worm gear and the classic 8-tooth spur gear found in Volvo set 30433—right down to the axle-cross hub and mould-ready fillets.
🏫 What you’ll learn
🔹 Driving a right-hand helix and sweeping a custom thread profile
🔹 Fast end clean-up with offset planes, through-all cuts, chamfers & fillets
🔹 Converting a stock McMaster-Carr gear into LEGO geometry via equation-driven edits
🔹 Realigning the axle cross 45 ° so the gear teeth index perfectly between spokes
📦 LEGO Set: Volvo Wheel Loader set 30433
📐 CAD Software: SolidWorks 2023
💬 Questions? Drop a comment or join the Discord: discord.gg/qYPKPVrAvT
🔔 Subscribe for future streams & edited tutorials.
🚨 NEW IN 2025 🚨
SolidWorks for Designers: Foundations → CSWA (7-hour guided course on Udemy)
udemy.com/course/solidworks-for-designers-foundations-to-cswa/?referralCode=72203B375E1FB455DFBA
📝 References
🔽 LEGO VOLVO WHEEL LOADER - FREE DOWNLOAD 🔽
Missed a file? Grab all SolidWorks (2023) or STEP files here:
fully-defined.kit.com/23e9f7758e
🕰️ Timestamps
00:00 Intro – Loose vs tight axle fits
00:46 Start the worm: base cylinder & centre bore
02:40 Helix maths & 30 ° sweep profile
05:10 Trim, chamfer & fillet the worm ends
07:20 Axle-cross cut-outs (4 × 1.9 mm)
08:26 8-tooth gear game-plan & reference images
10:40 Import a McMaster gear and strip unneeded features
14:20 Redraw a LEGO-style tooth; pattern × 8
19:00 Hub width to 7.8 mm + 3.8 mm flats
22:45 Rotate axle cross 45 ° for proper tooth spacing
24:30 Final fillets, colour swap & file export
26:15 Wrap-up, download reminder & next-episode teaser
🎥 Welcome to Episode 4 of the Fully Defined Build & Learn series.
Today we reverse-engineer the five-turn worm gear and the classic 8-tooth spur gear found in Volvo set 30433—right down to the axle-cross hub and mould-ready fillets.
🏫 What you’ll learn
🔹 Driving a right-hand helix and sweeping a custom thread profile
🔹 Fast end clean-up with offset planes, through-all cuts, chamfers & fillets
🔹 Converting a stock McMaster-Carr gear into LEGO geometry via equation-driven edits
🔹 Realigning the axle cross 45 ° so the gear teeth index perfectly between spokes
📦 LEGO Set: Volvo Wheel Loader set 30433
📐 CAD Software: SolidWorks 2023
💬 Questions? Drop a comment or join the Discord: discord.gg/qYPKPVrAvT
🔔 Subscribe for future streams & edited tutorials.
🚨 NEW IN 2025 🚨
SolidWorks for Designers: Foundations → CSWA (7-hour guided course on Udemy)
udemy.com/course/solidworks-for-designers-foundations-to-cswa/?referralCode=72203B375E1FB455DFBA
📝 References
🔽 LEGO VOLVO WHEEL LOADER - FREE DOWNLOAD 🔽
Missed a file? Grab all SolidWorks (2023) or STEP files here:
fully-defined.kit.com/23e9f7758e
🕰️ Timestamps
00:00 Intro – Loose vs tight axle fits
00:46 Start the worm: base cylinder & centre bore
02:40 Helix maths & 30 ° sweep profile
05:10 Trim, chamfer & fillet the worm ends
07:20 Axle-cross cut-outs (4 × 1.9 mm)
08:26 8-tooth gear game-plan & reference images
10:40 Import a McMaster gear and strip unneeded features
14:20 Redraw a LEGO-style tooth; pattern × 8
19:00 Hub width to 7.8 mm + 3.8 mm flats
22:45 Rotate axle cross 45 ° for proper tooth spacing
24:30 Final fillets, colour swap & file export
26:15 Wrap-up, download reminder & next-episode teaser
