Hey POB!
You said you just bought the performer kit today?
Well - why do'nt you look in the instruction manual? You should have a chart inside your kit!!!
The infromation should be available there, and if it is'nt - then call the place where you purchased the kit!!! Or better yet, call the factory in Denton, Texas!!!
I've got a set of old Linde-Union Carbide torches and two stage regulators I bought way back in 1983 with flashback arrestors, check valves, and gauge guards!!! still works like a champ!!! My chart says a number 5 tip should be used for 1/4" thickness but, I would'nt go by my chart because, Victor's numbers may or may not be the same!!!
Now as far as the gas rod is concerned, if you're welding, and if the base metal is mild steel, then an RG-45 or RG-65 should work well for you.
Just remember that you want to match up the diameter of the rod as close as possible to the thickness of the material, and most important of all - set your gas "working" pressure to 5psi on both your Oxygen and Acetylene. Set the flame to a "neutral" flame. This I can only describe to you as sounding quiet, and has a consistent sized inner cone (cone does'nt sputter or feather) so that the filler rod flows in smoothly, and you've got total control of the puddle!!!
Oh by the way - soldering is a process related to bonding and welding is a process related to fusion of two materials...
Respectfully
SSBN 727 Run Silent... Run Deep!!!