Place a couple of bricks together.Maybe 4.Make them into an inside corner shape to keep heat from escaping too quickly from mapp gas torches.Heat the finished spring by laying it in the "corner".you might want to use 2 mapp gas torches.Heat it evenly all over,keep the torches moving over the spring,until it changes from red into an orange color. If it is 01 steel,quench it in vegetable oil. If W1,use water that is not freezing cold..Quickly take tongs and submerge the spring vertically into about a 2 gallon water,or oil quench. Have it enter the quench end first,vertically. Stir the spring around in a circle as quickly as you can once it is completely submerged. The spring will now be very hard and should be treated like it is glass.Polish off the spring with wet or dry paper. Keep the spring free of oil. Place it back into your brick corner,and very slowly,and by degrees do your best to draw it to an even dark blue color.it is easy to get the spring too hot in one area,and have it go above blue to a gray color.Then,it is too soft and must be hardened again.If you get one part of the spring to a blue color before the other parts,quench it while it is still blue,wipe it off,and heat the other areas to blue. It might just be best to take the hardened spring and place it into a metal bowl with maybe an inch of motor oil in it,light the oil,and remove the spring after the fire goes out.No need to quench after this last oil heat proceedure. It should be a spring unless you got it too hot during the initial hardening. Any sign of blisters on the steel after the initial hardening means you burnt the steel and ruined it. The oil heating process will not make the blue appear,as the burning oil just leaves a black coating on the metal. The oil fire does give the same temperature as the bluing process. the spring will only break if you got it too hot,or if your design is wrong,has thin spots,holes drilled in it,etc.. I hope this posting isn't too confusing. P.S.,if you ruin the piece by overheating it drawing it to blue,you must normalize the steel. I take a pile of sand and get it good and hot with the torch. Heat the steel bright red,and shove it buried into the hot sand. Let the whole mass cool slowly. The spring should then be as soft to a file as when it was new. It has been re-annealed. Then,repeat the hardening and drawing processes. Be careful of your eyes when bending the new spring. They burst violently when they fail,sometimes they throw pieces at high velocity. I would not try using pre hardened stock,unless it is blue spring steel stock. Pre hard 4140 is too soft. The Brownell's stuff is water hardening. The only thing wrong with water hardening is that it can distort more than any other type of steel. All of the 19th.C. springs were made from it,though. If your spring must have a hole,pack steel wool into the hole tightly with a hammer and flat nosed punch. That keeps it from cracking from the hole. Avoid stamping figures on the annealed spring,too. that invites cracks also.