Stock definition and setup in CNC Programming

Introduction

Stock definition and setup tell the CNC machine what raw material size and shape to start with. This helps the machine know where to cut and how much material to remove.

When starting a new CNC machining job to set the raw material size.

When changing the material block to a different size or shape.

When programming the CNC to avoid cutting outside the raw material.

When simulating the machining process to check for errors.

When setting up fixtures and clamps based on the stock size.

Syntax

CNC Programming

STOCK X <length> Y <width> Z <height> [OFFSET <x> <y> <z>]

X, Y, Z define the size of the raw material in each direction.

OFFSET is optional and sets the stock position relative to the machine zero.

Examples

Defines a stock block 100 units long, 50 units wide, and 20 units high starting at machine zero.

CNC Programming

STOCK X 100 Y 50 Z 20

Defines a larger stock block shifted 10 units in X and 5 units in Y from machine zero.

CNC Programming

STOCK X 200 Y 100 Z 50 OFFSET 10 5 0

Sample Program

This program sets the stock size to 150x75x30 units. The CNC machine uses this info to plan cuts safely.

CNC Programming

STOCK X 150 Y 75 Z 30

; Start machining program
; Machine will know the raw material size
; and avoid cutting outside this block

Important Notes

Always measure your raw material before defining stock to avoid mistakes.

Stock setup helps prevent tool crashes by limiting cutting area.

Some CNC controllers may have different syntax; check your machine manual.

Summary

Stock definition sets the raw material size for CNC machining.

It helps the machine know where to cut and avoid errors.

Use OFFSET to position the stock if needed.