Originally Posted by
Mark Beaver
I’ve routinely used silver to braze these on, and haven’t ever had an issue. My preferred technique, which does take some practice to get stuff aligned nicely, is to heat up the spot on the tubing; melt on a small dollop of silver; hold the pump peg with needlenose around its neck, heat it up (well fluxed of course) until it’s at the brazing temperature then hold it onto the tubing while remelting the silver around and under it. I don’t look to get a fancy fillet around it. Best to practice a number of times on scrap until you get the hang of it. Or fabricate some kind of jig to hold it in place and braze as per usual, but I’ve not bothered with this.
I would recommend a small variation on that method:
Hold the BO in needle-nose pliers, hold the pliers in a vise with the BO sticking up.
Melt a drop of silver on the end of the BO
Hold the BO+silver against the tube by hand (steady your arm against another nearby frame tube)
Heat until the silver flows, most heat directed at the BO since the tube is sensitive and mission-critical, BO is not.
The other Mark B has the skill and experience to make his way 100% reliable but I think my way is better for a newb. Maybe better for anyone since you only heat the tube once.
I have used my method for various BOs including pump pegs, maybe around a thousand times. It takes less time than it took to type it out.
With the pegs in your photo, I would take a sec to miter the bottom to fit the curve of the tube. Silver wants as much surface area in contact as you can give it.