First Article

By Shailen Bhana, Mr

A useful note on first-off parts, where one measured sample can prevent a full sheet or batch from going wrong.

The first machined sample tells you whether the drawing, tool choice and machine settings are actually lining up. First Article is our note on checking that first part before the rest of the batch follows it.

First Article matters most when a new drawing, fresh sheet stock, or different cutter enters the job. One measured sample can catch a wrong offset, a loose tolerance, or chip-out on melamine before the nest repeats across the board. If you want to send setup details, use the contact form and include the part name, material, and machine used.

First-off checks that matter

• Critical dimensions measured on sample
• Edge quality checked on faces, pockets, and cut-outs
• Tool number and program revision recorded
• Operator and drawing issue noted clearly

A first article is not only about size on a tape. Hole centres, slot widths, pocket depth, and breakout on the exit side all need checking against the drawing and the intended fit. That is especially useful on cabinet parts, signage panels, and repeat components cut from full sheets.

How first-article checks guide custom CNC machining runs

First Article is where one checked sample can save a full sheet or a full batch. Measure the first-off part properly before the run continues, especially where board size, hole positions, or edge finish must stay exact.

Material choice changes what the sample tells you. MDF can hide edge fuzz until paint prep starts, while plywood may show veneer breakout and aluminium can reveal chatter if feed and spindle speed are wrong. In South African shops, sheet thickness variation and dust extraction performance can also show up on the very first part.

Keep the first sample with notes from the machine, not only a photo on a phone. Mark the top face, datum edge, cutter used, and any change made at the control after the initial cut. That record helps when the same job returns months later or moves to another router.

Workshop conditions that affect approval

A first article in Gauteng may cut differently from one near the coast if storage, humidity, or machine maintenance differs. Vacuum leaks, worn collets, and spoilboard condition can all influence whether the sample holds size across a sheet. Those issues are easier to correct after one part than after a full production stack.

Load-shedding interruptions, compressed air quality, and dust build-up around sensors can interfere with a dependable first sample. On coated boards, even a small change in tool sharpness may alter edge finish enough to fail the check. For aluminium, watch burr formation and heat marks before signing off the program.

Operated by Astros Marketing (Pty) Ltd from 2 Makro Place, Sunnyrock 1401.