Where I worked we had charts for all the materials and gauges (MS, SS, AL) and the dies they were formed on. But we also had material rolled to a specific thickness so any number for "standard" thicknesses wouldn't work out.
If you are doing work for some one else I would ask them what their preferred K factor/BA/BD is for the materials they are forming.
Usually, if the manufacturing managers/engineers, have their acts together, they would have formed some coupons of the material they are bending on all available dies and derived a set of BA and K factors for their material. That is something you could ask them to give you.
If you are doing work for yourself and bending on a hand brake then you could develop your own table of K factors by sampling some of your own bending coupons.
Short of that there are some online calculators that you could use.
Here are a couple:
Online bend deduction calculator. Automatically calculate bend deduction, bend allowance and K-factor for sheet metal fabrication and forming.
www.mform.com
Use our Bending Calculator to input material specs & get the bend allowance & deduction for your part. Watch our Bending Calculator video to see how it's done!
sendcutsend.com
