The bending allowance table is a table you make in advance and insert it when drawing sheet metal parts in the future. It will be added automatically according to the plate thickness.
K factor is mostly used for non 90 ° bending or large arc bending (it can be set according to the deduction of plate bending by your bending machine).
Bending deduction is to subtract a dimension from each bend (according to the plate thickness and lower die width, such as 2mm cold plate and 16mm lower die, the bending deduction is about 3.4mm; For example, if a 2mm sheet metal part has 20mm sides and 80mm sides, the unfolding length is 20 + 80-3.4 = 76.6mm). It can be set in the sheet metal option of the part you draw, or it can be set in the bending.
The K factor is usually not used.
However, for non 90 degree and large arc bending, the bending deduction is obviously not accurate, so the K factor must be determined;
The method is:
Draw a right angle sheet metal part, set a correct bending deduction, then click unfold, measure and record the unfolded size.
Go back and set a K factor, such as 0.25, and then click expand to see if the expansion size is the same as that just now.
If it is the same, the K factor is right. If it is different, go back and adjust the K factor until the unfolded size is the same as that deducted from the previous bend, then the K factor is right.
Write it down.
For plates of the same thickness, you can use this K factor to calculate.
Further reading: