For AI agents: the Markdown edition of this page is 4c.md; the site index for agents is llms.txt.

4C: CAD, CAM, CNC and CMM in one program. With an AI at the keyboard.

4C is one Windows program for the whole job. You design the part in a parametric tree (CAD), plan the toolpaths and watch the stock being cut in simulation (CAM), run the machine (CNC), and measure the part on the machine with a touch probe (CMM), without a post-processor or a file hand-off in between. An AI assistant can do the design and CAM work with you. It builds the same features a person would, in the same tree, so you can open any of them and change a dimension.

Five 4C screenshots of pocket toolpaths: circles, a slot, a freeform shape, a rounded rectangle and a pocket with an island — Pocketing in 4C: constant-engagement paths on round, freeform and island pockets.

A flange profiled in 4C. The control screen on the left is the same program.

4C showing a long aluminum plate with four pockets, toolpaths in green, in an isometric view — A plate with four pockets and its toolpaths, ready to simulate and cut.

4C on the shop floor

The program that drew the part is the one running the machine. These are real jobs on DM-controlled machines, most of them in DM's own shop in Chino, California, in 2017 and 2018.

Three photos: two billet aluminum intake manifold bases on a bench, a machining center running with the part on the table and 4C's 3D model and toolpaths on the screen, and four finished velocity stacks on a stool — 3D surface finishing: billet intake manifold bases on the bench, the job running with the model and toolpaths on 4C's screen, and the finished velocity stacks.

An operator at a DM vertical machining center pointing at the control screen, where 4C shows a five-lobed flange beside the job table — 4C is the control screen. The operator checks the flange's toolpath on the same screen that runs the machine.

A touch probe in the spindle with its ruby stylus inside a machined bore in a metal plate — The CMM side: a touch probe in the spindle, measuring a bore without taking the part off the machine.

Two DM vertical machining centers side by side in a shop, each with its 4C screen and an operator — Two DM machines in the DM shop, both running 4C.

Inside a DM machining center: a 4th-axis rotary table and its tailstock mounted on the machine table under the spindle — A 4th-axis rotary and tailstock on a DM machine. 4C programs and runs the rotary axis like any other.

Made in 4C by an AI assistant

Isometric render from 4C of an AC servo motor with a transparent housing, showing the stator, the copper windings, the shaft and the rear brake — An AC servo motor for a machine axis, designed by an AI assistant in 4C: 10 poles, 12 slots, a brake, 82 bodies. The housing is drawn transparent to show the windings.

Render from 4C of a grey plate with a round pocket, a rounded-rectangle pocket, a pocket with an island, a slot and four holes, with the toolpaths drawn in orange and green and the stock outline around it — A 150 × 100 mm aluminum plate: three pockets, a slot, four holes and an outside profile, modeled and given six toolpaths by an AI through 4C's MCP server, in one session.

Render from 4C of a car side mirror seen from the glass side, a dark lofted housing on a folding arm, mounted on a flat door panel — A car side mirror: lofted housing, convex glass, folding arm. An AI built it in 4C from a one-line request.

Render from 4C of a blue cable organizer, a long comb with curved fingers on a base with three feet — A cable organizer, one of the first parts an AI designed in 4C.

And four of the fourteen parts an AI built in one afternoon to exercise every corner of 4C, each step checked against a hand-worked number:

Render from 4C of a dark blue enclosure with a see-through lid held by four screws, seen from above at an angle — An enclosure as an assembly: box and lid are separate parts, placed and mated, with four M3 pan-head screws in tapped bosses. The lid is drawn see-through.

Render from 4C of a dark plate with two pockets and holes, with facing passes, pocket spirals and an outline toolpath drawn in yellow and the stock box around it — A plate whose thickness is a $variable: facing, two pockets, drilling, an outline pass and a chamfer, checked in the stock simulation with no gouges.

Render from 4C of a blue flanged hub with a central bore and six counterbored bolt holes — A flanged hub, the classic turned part: a revolve, six counterbored bolt holes from one patterned sketch, chamfered rim, filleted root.

Render from 4C of a brass-coloured sprocket with eighteen tooth gaps and a keyed bore — A sprocket: 18 tooth gaps cut by one patterned sketch, a keyed bore, every top edge chamfered.

Every one of these is an ordinary 4C part: a tree of sketches and operations you can open, measure and change. The AI built them through the same MCP tools described below, checking each step against the model's own measurements.

How the AI works in 4C

Connect. 4C runs a small MCP server on your own PC. It is off until you turn it on, reachable only from that PC, and protected by a token. Claude Desktop and Claude Code connect with one button. Your files never leave the PC; only the AI's thinking does.
Ask. "A 100 × 60 × 12 mm aluminum plate with four M6 counterbored holes 10 mm in from the corners." Or click a face in 4C and say what you want there.
It builds real features. Sketches with dimensions and constraints, extrudes, holes, fillets, patterns, mates. After each step it measures the result and corrects anything that does not match.
Then the CAM. Pockets, profiles, facing, drilling, chamfers, 3D roughing and finishing, with a simulation that reports gouges, leftover stock and rapids through material before anything moves.
You stay in charge. Every AI change is an ordinary operation in the tree: visible, editable, undoable. The AI never clicks 4C's windows, asks you to click when a face is ambiguous, and has no tool that moves the machine.

What 4C does


CAD	Parametric tree. Sketches with constraints, dimensions and formulas. Extrude, revolve, loft, holes with counterbores, fillets and chamfers, booleans, linear, grid and rotary patterns, primitives, surfaces. Assemblies with mates and placed instances.
Import and export	STEP, IGES and DXF in and out; STL out; circuit boards in from EAGLE files, with components. Replace a model with a new file and the toolpaths re-link.
CAM	Pockets including high-speed and patented constant-engagement pocketing, profiles, facing, drilling and canned cycles, chamfers and corner rounding, engraving, 3D roughing and surface finishing, 4th-axis and 5-axis work with tool-center-point control.
Simulation	Live material-removal simulation. Scrub back and forth; it reports gouges, rapids through material and holder contact.
Variables	One `$variables` table drives sketch sizes, toolpath settings and G-code. Change a value and everything follows.
G-code	Import G-code programs and run them beside 4C's own operations.
Machine control (CNC)	4C is the operator screen for a DM-controlled machine: tool table, tool changers, spindle, coolant, fixtures, handwheel, diagnostics.
Measuring (CMM)	A touch probe on the machine finds and measures features, sets work offsets, checks the finished part against the model, and captures points off an existing part so you can model it.
Languages	The interface is available in several languages.

What the AI costs you

Your own Claude subscription (Pro or Max), through MCP. No API key, no per-token bill.
Or your own API key in 4C's built-in chat panel, paid per token.
A free first taste, paid by DM, is being prepared for new users.

Getting 4C

4C runs on a Windows PC with or without DM hardware. Without hardware it designs, programs and simulates; connected to DM motion control it also runs the machine. A trial and pricing for 4C on its own are being prepared; DM supports it directly. Ask to be told when it is ready.