I've designed mechanical systems for startups across consumer electronics, robotics, and medical devices. The #1 reason prototypes fail has nothing to do with engineering skill — it's designing for the wrong manufacturing process.

Here's what I mean:

Your 3D-printed prototype works great. But when you try to injection mold it, the wall thickness is wrong, draft angles are missing, and undercuts make tooling impossible. Now you're redesigning from scratch — burning time and money.

The fix is simple: Design for manufacturing from day one. Even at the prototype stage, your CAD model should account for:

• Draft angles (1-2° minimum on vertical faces)

• Uniform wall thickness (avoid sink marks and warping)

• Parting line placement (where the mold splits)

• Material shrinkage rates (they vary 0.4-2% depending on resin)

This doesn't slow down prototyping — it actually speeds up your path to production because you're not redesigning later.

If you're a startup founder working on a hardware product and need an engineer who thinks about manufacturing from the start, that's exactly what I do at Tdesign.