brazing brass bolster (question)

[esa]

hello,i had a question on brazing brass bolster's onto D-2,i have done alittle and still in need of practice,but its comeing along,the question i have is should i wait until i have heat treated the blade then braze the brass on? will it hurt the hardness of the blade?,i think it is bolys book?i cant remeber his name but he said to braze before heat treating,but brass starts melting at 1750 and D-2 needs 1850 to treat,has anyone got information or doing this style of work on there blades.
thanks eric

[mete]

Often a soft silver solder [95Sn,5Ag ]is used ,which melts at about 440F. This can be used without damaging the temper. Brazing alloys melt at 1100F or higher , this will damage the temper .Also the hardening temp is higher than the melting temp of the brazing alloy.The solder must be designed for stainless steel [for D2 ] and the flux also. The other option is epoxy like JB Weld.

[RJ Martin]

Esa: Brazing bolsters works fine for carbon steel blades, as the HT temp is below the melting point of the brass bolster. You definitely don't want to use it on D2, as your bolster will end up in a puddle.
You are much better served by using a low temperature silver bearing solder, like Euectic grade 157 or Sta Brite to attach your bolsters, after heat treat.
Some guys are using epoxy-It is easier than solder, but, for me it lacks the aesthetic appeal of a beautiful solder joint.

[esa]

thanks for the help on this,the reason i was wanting to braze was like a cooper knife,wonder how he does his,i seen some on ebay and i like how the brass flows into the carbon steel thanks eric

[RJ Martin]

Cooper did them just like I said-He brazed the brass to Carbon steel, then heat treated with the bolsters in place. I believe he ground a recess in the blade, so that when the braze was radiused, it created a nice, straight line up the blade.

[esa]

so i guess the only steel that cooper could use is 0-1,being heat treating is 1500F. eric