I was in our local Tractor Supply yesterday to buy cat food. Looking around,I found a very substantial 36" bending brake for $299.00. It looked plenty rigid enough to bend brass saw backs. It was rated to bend a 1/4" x 2" wide piece of steel.
It didn't take up much floor space. I liked that feature. Also,it would bend the metal way past 90 degrees,into a "V" shape. Beyond that,careful progressive squeezing along the saw back with a non marring vise would complete the job.
If any of you aspiring saw makers want a way to bend the backs ( which I guess is a hurdle for many to over come),you might check out this brake. I don't know how many places have a Tractor Supply store,but they sell many useful things even if you don't have a tractor!!
I hope it isn't against TOS to mention a store.