Having worked in aviation parts machining for over 25 years, the most regrettable thing I’ve seen is a designer clearly needing ±0.03 mm, but the drawing specifies ±0.005 mm.
The result: machining time doubles, the scrap rate jumps from 2% to 15%, and delivery is delayed. And that tight tolerance? It wasn’t utilized at all.
Article Outline
A Real-Life Case of “Over-Engineering”
Tighter Tolerances Don’t Lead to Linear Cost Increases—They Skyrocket
Why Are Tolerances for Aviation Parts Often “Excessively Tight”?
How Is “Design Intent” Reflected on Drawings?
Three Practical Tips for Designers
A Few Final Straightforward Truths