Brass Brazing setup help needed

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I have an oxy/acetylene setup and trying to figure out what I should be using to braze with 3/32" thick brass rod.I have the following accessories: I look in the manual provided, and while it tells what settings to use for various tips, it doesn't tell what tip to use for what you are doing.  The book has guides for "MFA" an "MFN"I'm not sure which of these I should be using. I plan on brazing metal rods about 1/4" to 3/8" thick.
Reply:You CAN braze with either of those tips.  The tip on the left is actually for cutting.  The tip on the right is generally referred to a welding or brazing tip.What sort of joint are you using on the rods (just a butt joint, or overlapping them somehow?  Brazing the rods to other rods, or brazing the rods to plates?)For brazing, you are going to want a soft flame.  I'm not sure how much you know about setting up your torch, but I'll give you the basic parameters...For brazing: - Soft flame (won't be noisy at all) - Will be a carburizing (fuel rich) flame. - Light the torch with acetylene and turn it up to a bushy flame.  Add just a little oxygen, until it stops being bushy and produces two cones.  The outer cone should be a good 7 times the length of the inner cone for brazing.  When you waive the torch around in the air, it should move (unlike a welding, or neutral, flame...which stays the same shape when you move the torch around).  You are going to use the tip, or edge of the flame to heat, not the cone (different than welding, where you do use the cone). - The material you are brazing needs to be CLEAN - that means degreased and shiny.  Use 91 to 99 percent isopropyl alcohol to degrease the joints (available at your local pharmacy or supermarket for pennies, environmentally friendly, much safer than acetone and a fabulous degreaser).  Then scuff up the joint to shiny metal with a stainless steel brush or Scotch-Brite pad. - Brazing requires a pretty tight fit between parts too. - Brazing requires flux to work.  You can either get the flux-covered rods, or buy a separate flux. - You have to sneak up on the correct temperature.  This isn't welding.  You are NOT trying to melt the parent metal.  You are trying to melt the brazing rod.  Begin heating the joint you want to braze gently.  Keep the tip of the rod in the edge of the flame.  When the flux starts to run, you are close.  Start dabbing the rod in the joint until it begins to flow.  Move the heat ahead of the rod and the brazing filler will move toward the heat.  Be careful not to overheat.KevKevin / Machine_Punk from The Aerodrome Studio - Lincoln PowerMIG 210 MP - Meco N Midget w/custom welding station - Vintage Victor 100Current Projects: The Aerodrome Studio
Reply:I have used both of those kind of tips for brazing, but the one on the right would be what you want, especially with the thin rods you are wanting to use. The only reasons I have used the cutting tip for brazing is 1. it was the only one available at the time with the set up at hand or 2. I only needed to do one small spot quickly and did not want to change tips for just a short braze and then have to switch back. Just use the one on the right and you will be good to go.