Keep round-bottom flasks upright — anywhere on the bench

A set of round-bottom-flask stands in five sizes (100 mL → 2 L). Each one cradles the flask's sphere on a 45° conical seat that self-centres the glass and holds it on its lower hemisphere so it can't roll out. Standard 42 mm Gridfinity feet underneath — drop them into any Gridfinity baseplate, or stand them free on the bench. Designed and tuned for the Bambu P1S (also prints on X1 / A1).

Why the 45° seat works

A sphere resting in a 45° cone always contacts it on a circle of 0.707× the flask diameter — so the seat is forgiving of a few mm of glass tolerance and fits flasks from different makers. The contact band sits below the equator, so the flask nests securely instead of tipping.

Five sizes

• 100 mL — 2×2 · ~30 g · ~1 h
• 250 mL — 2×2 · ~33 g · ~1 h
• 500 mL — 3×3 · ~66 g · ~2 h
• 1 L — 3×3 · ~76 g · ~2¼ h
• 2 L — 4×4 · ~128 g · ~3½ h

Two base styles (both included)

• Tray — solid lipped floor: ties the feet and catches drips. The benchtop default.
• Lite — the same floor with drain holes bored through the outer cells: lighter and it drains, for a fume hood or wet bench. Both are in the downloads for every size.

Print notes

• Tuned for the Bambu P1S (256 mm bed). PLA, 0.2 mm, 3 walls / 15% gyroid. PETG works too if you'll see solvent splashes.
• Support-free — the seat is exactly 45° and the vent slots are arched.
• The size is engraved into the front edge of each base; no protruding tabs, so they tile edge-to-edge in a baseplate.

Original design and engineering. Licensed CC BY-NC.