What does a machinist need on a drawing?

Clear views, every dimension needed to make the part, tolerances on critical features, and material and finish callouts. A DXF or DWG of the geometry plus a dimensioned PDF covers most shops.

What file format do CNC machines use?

DXF and DWG are standard for 2D profiles, and STEP for 3D. Many shops also want a dimensioned PDF alongside the DXF for reference.

Do I need tolerances on every dimension?

No. Use a general tolerance for most dimensions and tighten only the features that mate, locate or seal. Over-tolerancing every number drives up the cost of the part.

How do I make a drawing for CNC machining?

What a CNC drawing must include

A machinist cannot cut from a picture. A drawing for CNC machining has to carry the information that turns geometry into a finished part:

Clear views of the part, enough to show every feature without ambiguity.
Every critical dimension, with nothing left for the shop to guess or scale off the page.
Tolerances on the features that mate, locate or seal, and a general tolerance for the rest.
Material and finish notes, plus thread and hole callouts.
The right file: a DXF or DWG of the geometry, usually with a dimensioned PDF.

The fast way to create one

If you have the part but no drawing, TechDraw AI gets you most of the way in minutes. Photograph the part, enter one real measurement to set the scale, and the tool generates the dimensioned views and a title block, then exports a clean DXF or DWG for the shop. It is the same workflow we cover in converting an image to DXF.

Get the tolerances right

Tolerances are where a CNC drawing earns its keep, and where AI hands off to you. Add them to the features that matter and confirm the critical dimensions with calipers before you send the file. Our guide to dimensioning and GD&T symbol guide cover how to call them out, and DWG vs DXF covers which file to hand over.

Machine shops do not care whether a human or an AI drew the sheet, only whether it is unambiguous and to scale. Confirm the critical dimensions, and an AI-generated CNC drawing is as acceptable as any other. More on that in will a machine shop accept an AI drawing.