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  1. #1
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    Fillet brazing with oxy-propane

    What tip(s) do I get for oxy-propane fillet brazing with a Smith AW1A torch? AW207 or ... ?

  2. #2
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    Not sure if victor tips work with smith handles, but for fillet brazing most here probably use a victor # 2 tip (some use a victor #4). The flame from the #2 is smaller than the #4. #4 works better for lugged subassemblies but some use it for fillets as well. If victors don't fit on your handle, find a conversion chart somewhere on line to find the bore of a victor #2 or #4 measured in either metric or inches.

  3. #3
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    Oh yes, make sure you have a T type hose. R and RM hoses only work for acetylene and will corrode if you pass propane through them.

  4. #4
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    For the Smith AW1A, you need to get the AT61 mixer (that includes an elbow with a threaded end that accepts separate tips) that attaches by hand to the end of the torch handle (this is a for-propane-only mixer) and NE150 tips (these are 5 propane specific small tips with various size orifices that thread onto the end of the AT61 elbow). Smith used to make propane specific single mixer/elbow/tip units that were designated with a "4" instead of a "2". For example the AW205 tip is designed for acetylene and the AW405 was for propane. Too bad they don't make them any more (I don't think). In our frame shop in Ukraine where we use propane, we use a Smith AW1A torch handle with AW205 and 207 tips. They work okay but not as well as my Victor J-28 and Uniweld 71 torch handle with a UN-J mixer and elbow with TEN tips attached. These are propane specific tips. The same mixer/elbow can accept TE tips designed for acetylene. The short recessed hole on the end of the propane tips help keep the flame from detaching.

    By the way I prefer using the AW205 tip size with my AW1A or Victor #1 tip size with my J-28 when using oxyacetylene for fillet brazing.
    Last edited by doug fattic; 11-29-2012 at 06:35 AM.

  5. #5
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    Thanks for the info, Doug. I just bought a Victor J-28 torch handle as the first piece of my OA setup. Cash flow requires me to acquire my setup one piece at a time. Tips might be next.

  6. #6
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    [QUOTE=doug fattic;9916281 They work okay but not as well as my Victor J-28 and Uniweld 71 torch handle with a UN-J mixer and elbow with TEN tips attached. These are propane specific tips. The same mixer/elbow can accept TE tips designed for acetylene. The short recessed hole on the end of the propane tips help keep the flame from detaching.

    [/QUOTE]


    Doug,

    good info in that post, thanks. Do you have an online source for the UN-J mixer and tips, or do you buy yours from your LWS?

    I've wanted to try Propane for some time. The screw in tip set up seems like a good way to go for experimenting with this.

    Alistair.

  7. #7
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    Thanks Doug and others for some really helpful information - most appreciated.

  8. #8
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    OK Doug I ended up with a uniweld 71 handle so I will get the victor un-j mixer and some TEN tips. Which of the TEN tip sizes do I need to cover typical bike work? (a #1, #2, and #3 ?) Also want to get one of the TEMFN rosebuds and they come in 3 sizes - guessing the #4 should be OK?

    Thanks

  9. #9
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    Quote Originally Posted by vintapperen View Post
    OK Doug I ended up with a uniweld 71 handle so I will get the victor un-j mixer and some TEN tips. Which of the TEN tip sizes do I need to cover typical bike work? (a #1, #2, and #3 ?) Also want to get one of the TEMFN rosebuds and they come in 3 sizes - guessing the #4 should be OK?

    Thanks
    The three sizes of Victor tips I use with propane are the #2, #3 and #4. The #3 is most commonly used for brazing lugs and the like. The #4 would be for heavier stuff like bottom brackets and the #2 for braze-ons. Personal preference may want to take it down a size. If one is skilled they may want even larger tips. I don't have an opinion on the size of a rosebud for propane use since I seldom use them and if I do it is with acetylene.

    The size of a tip that is best for a beginner is complicated by contrasting tensions. A smaller tip that keeps them from cooking a joint because they may pause or move in too close while adding silver is also problematic because their flame pattern often does not cover an area evenly and as a result provides inconsistent heat. It can take them a long time to get a joint up to temperature while perhaps overheating some smaller areas within it and burn off the flux. On the other hand, imprecise control of a bigger tip (that more evenly heats) may heat things up too fast to recognize how to how to adjust in time.

    In the last framebuilding class that ended a week ago, all three students preferred using propane over acetylene most of the time except when one was doing fillet brazing. Most of their general brazing work was done with a #3 tip. I had just gotten an oxygen concentrator for them to try out.

  10. #10
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    Thanks Doug really appreciate your advice!

    Happy xmas from New Zealand

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