When this applies
- Electronics, control or instrumentation housings
- One to a few dozen units
- A design that will change between revisions
- A need for a professional finished appearance
Specify the whole enclosure, not just the box
The metalwork is often the cheapest element. Everything attached to it is where the quote moves.
- Connector and display cutouts with positional tolerances
- Threaded inserts, standoffs and captive fasteners
- Gaskets, sealing and any ingress-protection intent
- Finish, colour and any silkscreen or labelling
- Earthing and paint-free contact areas
Material and thickness
Aluminium is light and easy to machine but marks readily; steel is cheaper and stiffer; stainless suits washdown and corrosive environments at higher cost and more difficult forming. Thickness should follow stiffness and hardware needs rather than habit.
Expect revisions
Prototype enclosures rarely survive first fit unchanged. Order the first unit alone, fit the hardware, then release the rest — and keep the cutout dimensions parametric in your model so a connector change is a quick edit rather than a redraw.
RFQ checklist
Include these in your request and suppliers can quote without a round of questions.
- 3D model including all cutouts and hardware
- Material, thickness and finish with colour
- Sealing or ingress requirements
- Quantity for the first build and likely follow-on
- Whether hardware is installed by the fabricator