From Drawing to First Article: How a Custom Junction Box Gets Made

Oct. 20, 2026

Custom enclosure projects rarely fail at the drawing stage. They fail between the drawing and the approved first part — where material, tooling and tolerances get decided without the buyer in the room.

Five stages that matter

Stage	What to fix
1. Drawing review	Wall thickness, draft angles, knockout and gland positions, gasket groove
2. Material and colour	Grade reference, UV stabilisation, flame class, a physical colour chip
3. Tooling	Mould design, steel and gate position, trial-shot plan
4. First article (T1)	Dimensional report, plus a fit check with real glands and DIN rail
5. Approval	A golden sample signed by both sides — the reference for every later batch

Where OEM projects usually go wrong

No tolerances on the drawing. Without them, T1 becomes a negotiation instead of a measurement.
Colour approved on a screen. Approve a physical chip or a moulded plaque, never an image file.
Nobody keeps a golden sample. Every later shipment is then judged against memory.

ZCEBOX keeps mould design and injection moulding in-house, so DFM feedback, trial shots and design changes run through one team. We develop OEM/ODM projects from your drawing or sample, run pilot batches before volume tooling, and supply standard sizes from stock.

General-purpose enclosures for ordinary indoor and outdoor installations — not designed for explosive atmospheres.

Send your drawing or target specification — we will return a DFM review and sample plan before you commit to tooling.

E-mail: sales@zcebox.com