Framebuilders - nickel silver? harris safety silv 50n
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i got ahold of some safety silv 50n brazing alloy. it contains around 50% silver and about 2% nickel. i was told that its good for fillet brazing, but not for lug work. is this true?
i know that it will not flow as well as the 56% stuff, but i aquired quite a bit of this stuff cheap.
velonomad
02-01-06, 09:29 PM
I picked up some 50n cheap myself at an auction. I haven't used it to build a frame but I did try it on a salvaged lug , The 50n flowed fine for me, it takes a bit more heat than 56. When I cut the lugged joint open afterward it had full penetration. Maybe there is other technical issues why you are not suppose to use it?
BTW if you use the Harris flux( not the best choice but it works fine) you might want to use the black flux for lugs. The white flux overheats easily on lugs.
I have used the 50n for braze-ons on my last two projects nothing has fell off yet.
Also the nickel alloy makes this stuff a little harder than 56 , makes filing off boogers a bit more work
poopncow
02-03-06, 12:25 AM
more silver = lower temperature to melt and flow. I recall that there were rules of thumb for the amount of gap based on percentageof silver. High silver content can go as low as .002", but should not be much more than that....but I can't remember how high is "high". The more brass, the thicker the gap needs to be, and the thicker the material will be when it flows. Therefore the higher brass content brazes are better for forming fillets, or fillinf looser fitting lugs. Please, all of this is stuff I read while in school, not from actual frame building practice, so threat it accordingly.
I will embark on the great journey of frame building soon, Jpogge, care to share your score on that braze material?
Nessism
02-03-06, 09:07 AM
50N is recommended for use on stainless due to it's wetting properties. For general framebuilding most builders use either 56% or 45% (often with cad).
i used the stuff and it works quite well, i think that 56% probably works better for lugs, it seems to need a little more heat to flow. its more liquid than 45% though.