models parts for 3D printing. Everything is in millimetres, Z is up, and the plate under the model is your printer's bed. What sits on it is what comes out.

It is built for parts that have to fit other parts: a gear on a shaft, a lid on a case, a screw in a hole. You type the numbers, the app builds the part, and your slicer gets a closed model of the right size.

SHAPES
• 36 shapes, each shown as a picture of itself: blocks, tubes, threads, springs, knurled knobs, vases and lettering
• Gears, sprockets, belt pulleys, chains, ratchets, cams, splines, worm drives and augers from module, teeth and pitch
• Panels and fittings: vent grilles, insert bosses, print-in-place hinges and ball joints, encoder discs, fans and impellers
• Name ornaments, snowflakes, stars and radial patterns
• A shape keeps its numbers: reopen it later and change 20 mm to 22 mm instead of drawing it again

WHOLE JOBS
• A case with a lid, vents and screw bosses
• A hose adapter, a fit-test coupon, a jigsaw, a QR code plate
• A sundial for where you live, a lithophane from a photo, an acoustic diffuser
• A cookie cutter, a stamp and a stencil from a drawing

WORKING EXACTLY
• Every drag lands on the snap step, and a number typed during a drag moves by exactly that much
• A ruler, sizes round the selection, kept measurements and guides
• Look inside a part through a guide plane without cutting it

CHANGING A BODY
• Add, subtract and intersect bodies
• Fillet and chamfer an edge, push and pull a face, cut ISO clearance holes for screws
• Lettering and texture on a face, cast a cavity, make a body lighter, repeat in a row or round a circle, mirror and align
• Sketches: extrude, revolve and sweep
• Trace a photo or a drawing into an outline, and model over a reference picture at its real size

BEFORE YOU PRINT
• Overhangs steeper than your limit turn red
• One check finds open surfaces, faces that cross, parts off the bed, parts too big for the printer and walls thinner than the nozzle
• A part too big for the bed splits into equal pieces pinned back together
• Pins, tongues, dovetails and snap fits between any two bodies
• Fit clearance, shrinkage and an elephant's foot chamfer in Settings

IN AND OUT
• Open in your slicer in one click: Bambu Studio, Orca, PrusaSlicer or any other
• Export 3MF, STL, OBJ and USDZ. 3MF keeps the unit, the names, the colours and where each part sits on the bed
• Import STL, 3MF, OBJ, USDZ, PLY and SVG
• Quick Look previews and thumbnails of projects in the Finder
• A part library and presets

INTERFACE
• Light and dark appearance
• A built-in manual in ten chapters, from your first part to keys and gestures, with a chapter on what the app does not do
• English and Russian
• No account, no tracking: nothing you make leaves your Mac unless you send it