When Two Identical Parts Don’t Behave the Same

We had a case where two batches of the same sheet metal part were produced using identical drawings and material.

On paper, they were the same.

But during assembly, slight differences were noticeable. One batch fit smoothly, while the other required minor adjustment during installation.

After investigation, there wasn’t a single root cause. Instead, it was a combination of small variations:

• Slight bend angle deviation within tolerance range
• Minor differences in coating thickness
• Tool wear between production runs

Each factor alone was acceptable. Together, they created a visible difference in assembly behavior.

It highlighted how manufacturability is often about managing variation, not eliminating it.

💬 How do you usually handle variation when everything is still technically “within tolerance”?

#sheet metal# #design guide# #tolerance#