The last one I did for myself was of 1095 at about 1/64". I shaped it over sized to fit the curve then heated with a torch to bright red/red orange and quenched in brine. No temper. Soldered it to the frizzen by first tinning the frizzen face well, set the half sole on it with plenty of flux, and applied heat from the back side slowly until the solder flowed and bonded. I used Stay Brite silver bearing solder which flows at 430°. That sounds a little high in temp, but for the short time of heat, I only got a slight temper. After testing it on the range, I found it yet too hard and oven tempered at 385° for an hour. That gave me the spark I wanted. For those wanting a harder face, a lower temp solder can be used, such as 60/40 which flows around 370°/375°, and the half sole could be pre-tempered if wished, however, it could not be re-tempered if found too hard, or of course the solder would melt. Locks seem to vary in the amount of frizzen hardness they do best with. My Siler does not do well with a really hard frizzen, but in experimenting with a L&R Queen Anne, I found it needed a very hard frizzen to be reliable. Early locks needing a half sole were most often brass brazed to the frizzen in the forge, and quenched while the frizzen was still red hot, or the half sole was riveted in place then hardened.