Soldering Stainless Steel Letters

Hello there again
I have returned this time with a few facts about which I would like your help Please.
First I have to make Stainless Steel Letters from 0.9mm, Grade 304 The
method of jointing is soldering and it's here I would like your help Please Solder is (Castoline 157 T.) Flux is (FL 4948.) Heat is from a small torch from a 1 Ltr / 1 Quart Cylinder via a 1.02Mtr / 3' long tube.I am told at full blast it can make up tp 400*C / 752*F. Will this Solder & Flux stay stuck to this kind of steel is there any better suited materials to make these joints, I have been practicing on some of the letters and there's some scorch marks what's the best way to remove these apart from not putting them there. any help tips will be very well received thanking you for your time and patience. Oliver...
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
Add image file
Upload is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.