The 3D preview

The CAD Preview tab shows the actual solid — the block with your channels subtracted from it — and rebuilds it as you change anything.

Driving it

Gesture	Does
Drag	Orbit.
Scroll	Zoom.
Fit	Re-frame the chip.

The grid on the ground is the build plate. The camera starts at a three-quarter angle and re-frames automatically whenever the model changes shape.

Display modes

Solid — the printed part as it will look. The mode for checking proportions, port bosses and overall shape.

Wireframe — edges only. Useful for seeing how the mesh is tessellated, particularly around a curved channel or a sphere.

X-ray — the block goes translucent and the channel network shows through it. This is the mode that finds mistakes. A junction that did not connect, a channel that stops short of its port, a chamber in the wrong place — all obvious here and all invisible in Solid.

Make a habit of switching to X-ray before every export.

Explode

Separates the two halves of a two-piece chip so you can see the bonding faces. Disabled on a monolithic chip, which has nothing to separate.

Worth doing before you print: it is where you notice that a channel is open at the split plane where you did not mean it to be, or that the lid has a feature on it you did not expect.

The statistics

Above the parameters:

Figure	What it is
Triangles	Mesh complexity. Affects file size and slicer time, not print quality.
Build time	How long the last rebuild took, in the worker.
Channel void	Internal volume in mm³. How much fluid the chip holds, and how much resin has to come out.
Ports	Count.
Chambers	Count.

Channel void is the number to watch. It tells you the dead volume of your device, and on a monolithic chip it is the volume of uncured resin sitting inside after printing.

How it is built

The geometry comes from manifold-3d, the same kernel modern OpenSCAD uses internally, compiled to WebAssembly and run in a worker — so a rebuild does not freeze the interface.

The pipeline is straightforward constructive solid geometry: a box for the chip, each channel swept along its solved path at its lofted cross-section, the ports and chambers unioned in, the whole channel network subtracted from the block, and finally the split plane applied.

Because it is a real geometry kernel rather than a preview renderer, the mesh you see is the mesh you export. There is no second, coarser preview model that could disagree with it.

When it is slow

A large gradient generator with dozens of segments takes longer than a Y-junction — it is more boolean operations. The panel shows the build time so you can see what you are paying.

If a rebuild is taking long enough to be annoying, the usual causes are a very large number of segments, or chambers on every corner of a long network.

What to check before exporting

1. X-ray. Is every channel connected the way you meant?
2. Explode, on a two-piece chip. Are the bonding faces clean?
3. Channel void. Is the internal volume roughly what you expected? A number far off usually means a channel is much wider than intended.
4. The Design checks panel, which is docked below this tab too.

Next

• Design checks — reading the panel.
• Exporting — STL, OpenSCAD, and the rest.