Brazing bits onto frame

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ian peacock
Posts: 40
Joined: 17 Sep 2012, 5:09pm

Brazing bits onto frame

Postby ian peacock » 11 Oct 2017, 2:28pm

Greetings again Earthlings, When brazing fiddly bits, like brake-cable stops, onto a frame, what is the best way to hold them in place prior to and during the process? I have successfully brazed all sorts of bits onto a couple of frames, but have resorted to simply balancing them on the spot where I want them to go, which is rather fiddly. A large clamp acts as a heat sink. What do the professionals do?
By the way, I have been getting the bits from Ceeway, they will supply stuff in very small quantities, and I recommend them. However, I think their website was designed before the advent of computers, but I don't mind because so was I. Ian

Brucey
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Joined: 4 Jan 2012, 6:25pm

Re: Brazing bits onto frame

Postby Brucey » 11 Oct 2017, 3:02pm

if you are using a very soft flame and a low melting point spelter you can use a high melting point wire to secure bits during brazing. But it is easier (I think) to use a spring clamp of some kind.

I have had good results using a springy stainless steel 'finger' with a shaped end to hold parts like cable stops against the tube; the amounts of force required are very small, and this arrangement does not constitute much of a heat sink. The finger runs lengthwise down the tube and a sliding collar can provide the clamping force.

BTW if you are worried about the braze metal joining the finger to the braze-on, coat the faces of each with a thin layer of typist's correction fluid; the braze metal won't wet onto such surfaces.

cheers
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breakwellmz
Posts: 1982
Joined: 8 May 2012, 9:33pm

Re: Brazing bits onto frame

Postby breakwellmz » 11 Oct 2017, 5:58pm

I used to use stainless steel wire, braze won`t take to stainless.

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Redvee
Posts: 2336
Joined: 8 Mar 2010, 8:58pm

Re: Brazing bits onto frame

Postby Redvee » 11 Oct 2017, 11:39pm

God gave us fingers for holding things :lol: :shock:

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Gattonero
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Joined: 31 Jan 2016, 1:35pm
Location: London

Re: Brazing bits onto frame

Postby Gattonero » 15 Oct 2017, 10:17am

ian peacock wrote:Greetings again Earthlings, When brazing fiddly bits, like brake-cable stops, onto a frame, what is the best way to hold them in place prior to and during the process? I have successfully brazed all sorts of bits onto a couple of frames, but have resorted to simply balancing them on the spot where I want them to go, which is rather fiddly. A large clamp acts as a heat sink. What do the professionals do?
By the way, I have been getting the bits from Ceeway, they will supply stuff in very small quantities, and I recommend them. However, I think their website was designed before the advent of computers, but I don't mind because so was I. Ian


old 13g stainless spokes are a good idea, you can bend them to suit your work. Just make sure you don't keep the flame too much on them, end of the day they are only for tacking.
Or better, the stays od SKS mudguards are beeefy and though not easy to manipulate "just by hand" they resist more the heat.
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since you have to sweat up the hills and coast down them.
Thus you remember them as they actually are...