Brazing fluxes: quality issue

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I'm no expert in any aspect of torch work, and I'm still learning things about brazing.  Wen I use coated brazz/bronze brazing rods, I find the flux is very good.  Thre's just too much of it on the rod, which makes for extra clean-up afterwards if the braze is going to show conspicuously.I bought some powdered flux from my local welding supply, and I had told the sales guy in the store that I wanted to use it with brass or bronze rod. He sold me a jar of stuff that says "silver solder flux" on the label, but he claimed it will work quite well for either bronze rods and steel, or with silver solder.  He said no problem.I've been comparing the results and ease of working with the coated rods versus dipping the hot rod end into this jar of "silver solder" for bronze brazing.  I have the overall impression that the coating on the rods is a better flux.  Can anyone clear this question up for me?  Thanks.Last edited by Joel_BC; 07-18-2009 at 02:31 PM.Reason: spelling
Reply:the silver solder flux is for silver soldering not brazing, silver solder will melt with an acetelyne turbo torch no  need for O/A. the  silver solder flux may be affected by the high heat of O/A.. Im no expert but have used both and found that to be the case for me
Reply:What type of flux (or what chemical composition) would you recommend for brass/bronze brazing with steel, using O/A torch for heat?
Reply:The conventional brazing flux in a can is reddish brown dry powder and the can has a smaller hole in the center of the lid so that you can leave the large lid in place and just dip through the center hole.  Canox markets a brazing flux and a similar flux intended for cast iron welding with cast iron rods.  I agree about too much flux on a coated rod.  Once you have some flux glass floating on top of your filler you really don't need additional until it is used up,  I use a lot on the first pass on a cast iron repair buttering the joint.  I then go back filling the vee and use very little flux relying on the residual left on the first pass.  The white flouride based water soluble silver brazing paste is not only hazardous but overkill for regular bronze brazing.alloys.I am betting the metal cans now are replaced with plastic... that dates me.Last edited by lotechman; 07-19-2009 at 12:49 AM.
Reply:Originally Posted by lotechmanThe conventional brazing flux in a can is reddish brown dry powder and the can has a smaller hole in the center of the lid so that you can leave the large lid in place and just dip through the center hole.  The white flouride based water soluble silver brazing paste is not only hazardous but overkill for regular bronze brazing.alloys.I am betting the metal cans now are replaced with plastic... that dates me.
Reply:Then there's the question of availability. I called around to all the welding-supply stores within an hour's drive of my place, and all are currently carrying only the (silver-solder) white-powder or white-paste "brazing" flux.  A couple stores told me that if I can come up with a brand name for the reddish powder stuff - the stuff that's supposed to be better for brass/bronze brazing of steel - that maybe they can order it for me.So, in a way, I'm back where I started.  Any advice on this?  Thanks.
Reply:I would use Google and check suppliers on the Internet.  They have all sorts of data sheets that can point you in the right direction.  They even have tech support experts.  A lot depends on what specific application you want to braze.  There are tailor made products.  Sometimes, the available clerk at a welding supply store amounts to a clerk that does not know a whole lot.  Way back when I was a manufacturer's rep, I used to support a welding supply store where the store manager and sales reps were all business majors who got started in the business with absolutely ZERO welding/brazing experience.
Reply:Refer to this MSDS sheet first, then Esabs site second. I'd think Harris would be another good reliable source.http://www.airgas.com/documents/pdf/...state/21-b.pdfhttp://products.esabna.com/EN/home/f...llstate_fluxes
Reply:This little site describes using the rod dipped in powder,  " hot rod"http://www.jm-metaljoining.com/pdfs-...x%20Powder.pdfOn this listing the Harris powder is in a version for welding cast iron and the other one is general duty for brazing steel and iron.http://www.jwharris.com/consumables/fluxes.aspThe most effective way to have my customers use up product would be to supply in a glass jar that will fall and break or a plastic container that will melt when set down in the wrong place.   This brings up the story of a potato peeler company making their peelers the colour of newspaper so that they would get wrapped up and thrown out.,,, sales skyrocketed.