Article Technical inputs

How to prepare drawings for CNC machining and gearing

A practical overview of inputs that help quote a CNC part, gear, or gearbox component repair faster.

A good drawing shortens the path from request to quote. For CNC machining, gear production, and gearbox-component repair, the useful input is not only the part shape, but also material, tolerances, quantity, and target delivery date.

For a gear wheel, pinion, or shaft, include module, tooth count, diameter, width, fits, and functional surfaces where available. For repair parts and replacements, a photo or sample of the existing component is often useful too.

Before sending a request, check that the expected delivered output is clear. The more precise the input, the faster a supplier can identify risks, price the work, and confirm a realistic timeline.

What should a part-production request include?

Input What it clarifies
Drawing Dimensions, tolerances, critical holes, fits, and functional faces.
3D model Part shape and possible clashes that are easy to miss in a drawing.
Material Machinability, strength, availability, cost, and possible surface finishing.
Quantity Difference between one-off production, small-batch production, and repeat work.
Gear parameters Module, tooth count, diameter, width, and gear type.
Lead time Requested lead time, reviewed according to difficulty and material availability.

Drawing checklist before sending a request

  • Are functional dimensions, fits, and mating faces marked?
  • Is it clear which dimensions are critical and which are supporting?
  • Is material named, or is the operating environment described?
  • Are basic gear parameters included where relevant?
  • Is it clear whether the job is new part production, replacement, or repair?

Frequently Asked Questions

Is a photo of the existing part enough?

A photo helps with repair and replacement parts, but it does not replace dimensions, material, and tolerances. It works best with a drawing, sample, or description of the part function.

When should 3D data be included?

3D data helps with complex shapes, milled parts, gearbox components, and areas where installation or assembly clashes may occur.