Engineering notes: DFM, CAD, prototypes

Short, practical write-ups from the engineer who actually does the work: what makes parts cheap to make, what breaks at tooling, and how to hand over CAD so a supplier doesn't have to guess.

Exploded sensor enclosure showing housing, gasket, lid and PCB

Sheet metal · October 26, 2026 · 6 min read

A DFM Checklist for Sheet Metal Parts I Run Before Any Quote

My DFM checklist for sheet metal parts: thickness, bend radius, flange length, holes near bends, reliefs, tolerances and finish, with the numbers I use.

Exploded sensor enclosure showing housing, gasket, lid and PCB as separate parts

CAD · October 26, 2026 · 6 min read

STEP vs STL: Which File Should You Send a Manufacturer?

STEP vs STL for quoting: what each file really contains, when a mesh is fine, and the export mistakes that cost suppliers (and you) a day.