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Old 06-05-10, 06:29 PM
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JohnDThompson 
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Originally Posted by unterhausen View Post
the problem with using a torch to un-braze canti posts is that they are probably put on there with brass. The remelting point of brass is high enough that it's fairly easy to rip the tubes if there is a small part that isn't loose when you start tugging on it.
Position the frame so the bosses are pointing straight down, with a bucket of water underneath. Keep the flame on the bosses as much as possible while heating. When the brass is fully melted the boss will just fall off into the bucket. At that point you can use a wire brush and/or a solder wick to remove residual brass from the stays. If you're lucky/good enough you will have minimal clean up afterward.

N.B. Mapp/air may not be hot enough to melt the brass effectively; if you can use Mapp/oxygen or oxy/acetylene you will have better luck, and it will be much faster meaning the heat-affected area on the stays will be much smaller.
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