How to calculate the bending radius of sheet metal?

What you really need to know should be the R on the neutral plane. The neutral plane is biased to the inside.

If you round it up, it must be the inner R.

Generally, the neutral surface of SPCC plate is 0.445t from the inside to the outside.

The internal R angle cannot be calculated. This is related to your bending tool. Different bending tools have different inner R, which can only be said to be similar.

Bending tools can be divided into sharp punch and radius punch.

The precision sheet metal can be calculated as follows after rounding: inner radius A + inner radius B + 0.35T = unfolded dimension C