20 µL chamber chip, 350 µm deep

Internal geometry — X-ray

X-ray see-through view of 20 µL chamber chip, 350 µm deep: plan footprint (true scale) and z-exaggerated isometric of the internal chamber, feed channels and two bores

See-through internal view. Left: fluid footprint in plan, true scale (teal); ports show as the wider circles. Right: isometric of the internal void, vertical z exaggerated 3× for visibility. The exterior is an opaque solid block — this is what is inside it.

Download: PNG (x-ray)

Longitudinal section & exterior

Longitudinal y=0 section of 20 µL chamber chip, 350 µm deep: grey solid, white chamber, channels and bores

Exterior isometric render of 20 µL chamber chip, 350 µm deep (opaque block with two top bores)

Longitudinal section at y=0 (left): grey = solid, white = fluid voids. Exterior isometric (right): the outside of the CAD model, drawn opaque. Click either for full resolution.

Download: PNG (section) · PNG (top) · PNG (iso)

Description

A single monolithic resin-SLA block with one 20 µL, 350 µm-deep stadium reaction chamber, two straight 0.5 mm feed channels on the same floor, and two Ø1.5 mm vertical access bores to the top surface. Footprint 29.9782 × 7.7809 × 2.15 mm.

The target is a 20 µL chamber, 350 µm deep. The model reproduces it exactly — the mesh measures 19.9955 µL, -0.022% from target. The stadium is sized by an inverse-solve: area = volume ÷ depth = 57.1429 mm², then a width chosen to hold the same stadium aspect ratio (L/w = 2.7146) as the 20 µL chamber chip, 500 µm deep — that is w = √(A/2.5) = 4.7809 mm, giving a chamber length of 12.9783 mm.

Verification

metric	value
Chamber volume — target	20 µL
Chamber volume — measured on the model's mesh	19.9955 µL (-0.022% vs target)
Chamber depth — target	350 µm
Chamber area (volume ÷ depth)	57.1429 mm²
Chamber stadium (L × w)	12.9783 × 4.7809 mm
Stadium aspect ratio (L/w)	2.7146 — held from chamber_20ul_500um so the family is geometrically similar
Footprint (L × W × H)	29.9782 × 7.7809 × 2.15 mm
Chip watertight	True
Chip Euler number	0 — genus-1: one cavity, two vents
Void connected bodies	1 — chamber and both bores continuous
Min feature vs Phrozen 12K X (px_min = 350/19)	18.42 px
Min feature vs Phrozen 12K Y (px_min = 350/24)	14.58 px
Min feature vs BYU Nordin (px_min = 350/7.6)	46.05 px

All geometry checks run with trimesh (merged vertices) on the exported STLs. See the bundled README for the full method. The minimum-feature rows are pixel counts; for each printer’s process limits, see Hardware and process.

Cross-family consistency. This inverse-solve reproduces the target volume to -0.022% here, and to within 0.023% on every chamber in this family — the 2.5, 5, 10 and 50 µL chambers and the 20 µL chambers 350 and 500 µm deep. Agreement to three decimal places across a 20× volume range shows the solve behaves identically at every scale.

Print adaptation

Chamber (target → drawn): 0.35 mm deep — as targeted; no print enlargement applied
Chamber volume: 20.0 µL target / 19.9955 µL in the model (mesh)
Target printer: Phrozen Sonic Mighty 12K — 19 µm (X) × 24 µm (Y), non-square

Target dimensions are what the design aims at; drawn dimensions are what its CAD model is drawn at. Where the two are the same number, no feature was resized to print.

Credits

Design: Ali Tahmasbizadeh, Gale Lab, University of Utah.

Files to download

SCADchamber_20ul_350um.scad12.1 KBDownload
STLchamber_20ul_350um.stl210.8 KBDownload
STLvoid_chamber_20ul_350um.stl207.9 KBDownloadFor inspection, not for printing: the fluid network, every space that holds liquid, as a solid.
PNGchamber_20ul_350um_xray.png147.0 KBDownload
PNGchamber_20ul_350um_section.png18.6 KBDownload
MDREADME.md1.4 KBDownload