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  1. #1
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    Front triangle tacking question

    I took a frame building course a little over a year ago and I am just now set up to do some building on my own. Not everything I have learned has stuck in my head so I have a question about taking up the front triangle.

    (Using oxy-acetylene fillet brazing)
    I tacked up the front triangle of a frame yesterday and before I did I thought, "hmmm maybe I should tack the st-bb joint and tin the front part that is going to be covered by the DT." so thats what I did. I thought that I should because I wouldn't be able to access that area later. The only problem is that it made my DT cope/miter not fit as well because of the brass and hardened flux. So I filed off the flux and got the joint looking pretty good but still not as nice as original and proceeded to finish tacking the frame.

    My question is, How do you go about taking up this area? is it necessary to fill the front of the st-bb joint?
    I should mention that this frame had a pretty large compound miter on the dt because the st is the true temper s-bend type.

  2. #2
    Senior Member Nessism's Avatar
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    Standard process is to get your miters to within 1mm gap to the mating tube. If you achieved this, all is good. If not, pull the joint apart and file off that extra filler to restore the proper joint fit.
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  3. #3
    Framebuilder
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    [QUOTE=G0balistik;6444486.

    My question is, How do you go about taking up this area? is it necessary to fill the front of the st-bb joint?
    I should mention that this frame had a pretty large compound miter on the dt because the st is the true temper s-bend type.[/QUOTE]

    Necessary? Maybe not, but, neither I or any other builder I know would leave that part of the joint untouched. I always tin it and then put a fingernail sized fillet on top, just to be sure. After you've done it a few times you won't be leaving brass where it will interfere with your compound miter.

  4. #4
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    Thanks, that was I was looking for. I didn't think it would be good to leave it untouched, next time I will just make sure to be more neat with the small fillet. The joint was definitely tighter than 1mm, it was contacting in most areas.

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