Universal Car Cup Holder Expander – Mug & Large Bottle Adapter (Fully Parametric)

Universal Car Cup Holder Expander – Mug & Large Bottle Adapter (Fully Parametric)

Tired of factory cup holders that can’t handle a real mug with a handle, a big tumbler, or your favorite oversized water bottle? This clean, two-piece adapter fixes that instantly and looks good doing it.

A sturdy lower base threads securely into your vehicle’s existing cup holder. The upper sleeve then screws onto the base, instantly transforming it into a tall, wide, rock-solid holder with a full-height side slot so mug handles pass through with ease while the rest of the cup or bottle stays perfectly supported.

Every dimension is driven by variables in the public OnShape document, so customizing it for any vehicle is effortless. Change the base diameter, height, or upper sleeve width in seconds and export fresh STLs.

Three upper sleeve variants included:

• Blank – smooth and minimalist

• Heart of Crosses – subtle raised crosses arranged in a heart shape, a quiet faith-inspired touch that makes a great gift

• NEW - Hexagon spiral - a helix pattern of hexagon cutouts. Saves material and looks awesome!

Features:

• Threads together for a rock-solid connection

• Generous full-height handle slot

• Thick, strong walls with comfortable edges

• Prints support-free with properly tuned bridging

Important: Cars get extremely hot in summer. Print with a heat-resistant filament such as ASA, ABS, PETG, PCTG, or HT-PLA. Standard PLA will deform or melt.

Whether you’re commuting, road-tripping, or overlanding, this adapter finally lets you bring the drink you actually want — without spills. Fully parametric, endlessly adaptable, and ready for your printer right now.

Download the STLs or open the OnShape link to customize, and enjoy proper drinks on the road. Happy printing and safe travels! 🚗☕🙏

Update: I adjusted the thickness and added a new hexagon version to lower material costs a bit.