I am going to try to make this bumper 1/4 in stainless I think its 1.2mm but will strengthen with flat stainless bar at the back, any help or advice to go about it
It can be made in one piece with the top flange having cuts on the curve and then welded (same with the bottom flange if it has one), it depends what you have to bend and shape the steel with.
As spark plug rightly suggests...play with cardboard first and see how it works.
Looks like there's several ways to make that in one piece without welding... if your swager is man enough (16swg / 1.6mm mild steel is about equal to 20swg / 0.9mm stainless capacity wise for folders, jenny swages, shears etc) could freehand it using tipping dies to slowly work the top edge over before finishing by shrinking the flange to get it the full 90°. Various vids on youtube showing tipping dies in action if you're not familiar with them
Another way is to cut out a hammer form and just work the edge down against that
That's 1.2mm 304L, while wood is usually good enough for ally or 0.9mm mild steel it won't stand upto the amount of hammering needed on 1.2mm stainless. Especially if/when you need to stretch or shrink a deeper flange. For deeper parts can combine a wooden former with a steel top edge, that example is just a piece of 6mm steel as the return is small. Made a hammer form as i needed several identical pieces and they were each made from two mirror image halves which the form will do depending which side of it you use
As it doesn't like there's much of a radius on the bend line personally i'd probably use something thicker as it's a bumper, cut the top profile out, bend the other piece & join 'em with an outside corner weld before linishing and polishing the weld out. Assuming there's access to a TIG i'd make the joint a closed outside corner and weld it autogenously which'll put most of the radius in minimising the amount of linishing. http://www.mig-welding.co.uk/forum/threads/tips-on-pulsed-tig-welding.9743/#post-111146
So the main issue you then face is the cost of a Reel of the right wire and the gas
I keep saying this but often your better getting bits done out at a shop set up for it. No shame in it just a heap of common sense - fight the battles you can decisively win
cos steel goes rusty if I leave the car in the garage for a few years
trouble with Lazze is it makes me want to make loads of things , just too inspiring