brazing basics

[banditboy]

i can mig weld,and solder,
but i need to braze a nut onto a stud to remove it from a cyl head,s/steel stud, onto steel nut, is this a good idea....

which blow torch do i need,
propane,map and oxyegen,
i dont want to invest a fortune in the kit at it will only get the odd use,

do i just feed a rod into the heated work, are the rods fluxed,

im looking forward to having this skill, but need a few pointers

thanx in advance

 

[Burnerman]

Still no joy then.....
I would doubt if anything other than oxy acetylene would work here, but Mapp gas has a chance....it depends on how much heat is absorbed by the cylinder head. You will have to heat the stud bright red hot - nothing else will do.
Use a pink flux called Sifbronze, and a non fluxed brazing spelter (the rod) for best results. The flux vitrefies at high temperature, and if you can get the stud and nut hot enough, the brass spelter will flow in, just like solder.
If you can get your bike to a welder, he will probably use a no.2 nozzle, and a carburising flame - thats a flame with excess acetylene. I do feel this would be your best bet!
John

 

[MANDATE]

Have you tried a stud extractor? Have you applied 'plus gas' and left for 24 hours?
Can't see the brazed nut idea any better than using a stud extractor.
The stud extractor exerts the force adjacent to the cylinder block/head which you can't do with a brazed on nut.
Also I would be concerned about any damage that may result from using heat.
I believe brazing rods can be either ready fluxed or you can use plain rod in conjunction with powdered flux as I recall.

 

[banditboy]

just to get you up to speed on my problem....[see link below]

ive done nothing new since last week,
im trying to braze a nut on to the s/steel stud which is 7-8 mm long,

ive soaked it for a few days,
i realy dont want to try drilling it as its s/s,,and fear the extractor will break of in the stud....

//www.diynot.com/forums/viewtopic.php?t=213070&highlight=

 

[WDIK]

you wont braize to s/s, and it would break even if you could, try tig