How to order boards with 70 um thick copper?

[ruifeng.zhang]

@va26

I showed you the actual measured thickness of copper, admit that there is measurement accuracy up to 0.005mm. But actually I’m interested in the original thickness of the copper before the technical processes. If I order production boards with 2oz copper thickness, it is expected that this means the original thickness of the copper - 2oz. Thank you.

The actual thickness cannot be measure by Caliper, but have to tested by the professional Copper Thickness Tester. You can ask any PCB Fab in the world to see if your measurement is correct.
If you order a 2oz board, the original copper will be 1-1.5oz, and start processing. The outcome will be 2oz.
If you want the original copper 2oz, the outcome will be 2.5-3oz after processing. Thanks.