# do it at home brazing...



## Fulton (Feb 6, 2004)

i've got a steel frame that i want to add some cable stops to. Not building anything structural here. I've done some brazing in a jc welding class so i think I can make it work.

Anyway I can do this with a propane torch? I don't have access to an oxyacetylene torch. I don't mind having to purchase tools for this, and don't tell me to take it to a local welder/frame builder, i want to do this on my own.

so what will i need?

thanks


----------



## Walt (Jan 23, 2004)

*Here's a list...*

A little propane torch probably won't generate enough heat. One of those cheapo MAPP/Oxygen torches will, though, and you can get one at a hardware store. Try the propane torch first if you've got it, though - I just don't know if it'll work very well unless it's got some kind of pressurized oxygen line as well to make it burn faster/hotter.

You'll need:
-All-State S-200 flux (or equivalent)
-56% (preferable) or 45% cadmium free silver (buy as small of an amount as you can - it's running upwards of $20/ounce right now)
-Something to hold the brazeons where you want them. You can improvise something from metal spring clamps or c-clamps pretty easily.

Let us know how it goes!

_Walt



Fulton said:


> i've got a steel frame that i want to add some cable stops to. Not building anything structural here. I've done some brazing in a jc welding class so i think I can make it work.
> 
> Anyway I can do this with a propane torch? I don't have access to an oxyacetylene torch. I don't mind having to purchase tools for this, and don't tell me to take it to a local welder/frame builder, i want to do this on my own.
> 
> ...


----------



## rodar y rodar (Jul 21, 2006)

Silver instead of bronze? Is that preferable due to the size of cable stops or just because he`s looking to do it with propane or MAPP?


----------



## Walt (Jan 23, 2004)

*Both*

Silver flows easier for doing small stuff (though you can certainly do it with bronze) and the bronze will take WAY more heat. I'm pretty sure the MAPP torch will do bronze, but I doubt the propane one will. Just trying to give him some advice that will work with the equipment he has at hand.

For what it's worth, most brazeons are done with silver, partially because it flows smoother and easier (and you don't need much) and partly because you can make the tubes warp pretty significantly at bronze brazing temps. You can also warp 'em at silver temps, but not as easily or as much. The only small bits I usually do with bronze are canti bosses.

The disadvantage, especially for a beginner, is that it's really easy to burn the flux with silver, and once you do that, you've gotta get boiling water to clean it off before you can try again. It's very hard to burn the flux with bronze - I've seen people blow holes in steel tubes with their O/A setups when learning and still manage to flow brass onto them, because the flux was still working.

-Walt



rodar y rodar said:


> Silver instead of bronze? Is that preferable due to the size of cable stops or just because he`s looking to do it with propane or MAPP?


----------



## 1speed1der (Apr 19, 2005)

sorry to butt in....

so if a mapp gas torch is hot enough to add braze ons it will be hot enough to remove some? i wanted to add a canti cable hanger bridge on a frame and also get rid of some cable stops (single speed cx project).

TIA walt....it is great having you here.


----------



## velocipus (Apr 27, 2005)

1speed1der said:


> sorry to butt in....
> 
> so if a mapp gas torch is hot enough to add braze ons it will be hot enough to remove some? i wanted to add a canti cable hanger bridge on a frame and also get rid of some cable stops (single speed cx project).
> 
> TIA walt....it is great having you here.


I was able to remove cable stops and shifter braze-ons pretty easily with a MAPP torch.


----------



## Walt (Jan 23, 2004)

*Yes*

Get some vise-grips and your MAPP torch, and make sure you've got plenty of ventilation. I would recommend removing all the paint/powdercoat in the area of the brazeons beforehand, but if you're doing it outside, you don't necessarily have to. If you don't have vise-grips, any old pliers are fine. Just heat the brazeon up until it's glowing (keep the heat on the brazeon, not the frame) and then *gently* pull it off with the pliers. Make sure you're on a concrete surface with nothing flammable around, because when you drop the brazeon, it's going to be at like 1000 degrees plus. If it's not coming off, keep applying heat and gently pulling - if you start yanking too hard, you run the risk of tearing/deforming the tube underneath.

Good luck!

-Walt



1speed1der said:


> sorry to butt in....
> 
> so if a mapp gas torch is hot enough to add braze ons it will be hot enough to remove some? i wanted to add a canti cable hanger bridge on a frame and also get rid of some cable stops (single speed cx project).
> 
> TIA walt....it is great having you here.


----------



## NEPMTBA (Apr 7, 2007)

I usually wipe it quickly with a thick shop rag while the area is still hot. I also have a welding glove on as not to burn my hand. Be careful this stuff will splash went it's that hot. This removes most of the old brass or silver solder. Then just clean it up with emery cloth... Wallah Finito'


----------



## Walt (Jan 23, 2004)

*Um...*

Let it cool, then file/sand off the excess filler. Wiping liquid metal with a rag is a really bad idea.

-Walt



NEPMTBA said:


> I usually wipe it quickly with a thick shop rag while the area is still hot. I also have a welding glove on as not to burn my hand. Be careful this stuff will splash went it's that hot. This removes most of the old brass or silver solder. Then just clean it up with emery cloth... Wallah Finito'


----------



## NEPMTBA (Apr 7, 2007)

Walt said:


> Let it cool, then file/sand off the excess filler. Wiping liquid metal with a rag is a really bad idea.
> 
> -Walt


 Many years as a Welder and always works for me! Just gotta make sure were talking brazing here and not heating the base metal to cherry red. Brass melts before steel, so it doesn't harm the base metal. Ever see a plumber wipe a pipe? Filing can cause damage as well, especially in the center of a tube as with a braze on. Just my take... respectfully... not arguing.


----------



## Walt (Jan 23, 2004)

*Please keep in mind:*

The OP and others who have asked questions do NOT have years of metalworking experience, or even basic welding safety training, most likely. The *safe* route here is to remove the brazeon, then carefully sand/file away the silver or brass. It's easy to do this without damaging the tube, and there's no risk of setting things on fire. I'm guessing that the folks who are asking questions here do not even own welding gloves, too.

I'm not trying to pick fights, just please try to remember that the advice you're giving is going to an audience that does not necessarily have much framebuilding/welding/metalworking experience, and as such, I think we should always recommend the safe/slow way of doing things over the "pro tricks" that are faster but require more skill and/or danger. Folks may be working in their garage around flammable materials/kids/pets/etc. Spraying hot metal around is counterindicated.

-Walt



NEPMTBA said:


> Many years as a Welder and always works for me! Just gotta make sure were talking brazing here and not heating the base metal to cherry red. Brass melts before steel, so it doesn't harm the base metal. Ever see a plumber wipe a pipe? Filing can cause damage as well, especially in the center of a tube as with a braze on. Just my take... respectfully... not arguing.


----------



## NEPMTBA (Apr 7, 2007)

Walt said:


> The OP and others who have asked questions do NOT have years of metalworking experience, or even basic welding safety training, most likely. The *safe* route here is to remove the brazeon, then carefully sand/file away the silver or brass. It's easy to do this without damaging the tube, and there's no risk of setting things on fire. I'm guessing that the folks who are asking questions here do not even own welding gloves, too.
> 
> I'm not trying to pick fights, just please try to remember that the advice you're giving is going to an audience that does not necessarily have much framebuilding/welding/metalworking experience, and as such, I think we should always recommend the safe/slow way of doing things over the "pro tricks" that are faster but require more skill and/or danger. Folks may be working in their garage around flammable materials/kids/pets/etc. Spraying hot metal around is counterindicated.
> 
> -Walt


 Yes, Walt you are correct and I didn't mean to come across in a wrong light. That's why I said respectfully to you as I do not in any way try to argue. I guess "my way" is well "My way" Sorry to thoses who I misguided. It is very hard to pick the brass out of the nylon rag though!...kinda like solder on the good living room carpet...LOL!

Build on! :thumbsup:


----------

