Hello.
I purchased a Crack with the speedball upgrade in March and just now have the time to start building it. While looking for solder with Bottlehead's recommended metal content (I only had 95/5 tin/antimony solder), my grandma gave me solder that my grandpa used when he was working for the Bell Telephone Company. There is no metal content listed, and I have spent hours searching the internet and different forums hoping to find more information about it, specifically the content. The spool reads:
Nassau "Pedigreed" Pure Water White Rosin Core Solder, C Rosin SPEC-AT-7076, (5lbs made by Nassau Smelting and Refining Co. Staten Island New York).
As I said, I would love to know more about it. While searching the internet, I found that 5lb spools of this stuff sells for hundreds of dollars, so I imagine that it is quite good solder. My grandma said that it is at least 30 years old, so I imagine that it has a pretty high lead content.
What does everyone think? Should I try using it to build my crack? If needed, I will post a picture of the spool. Thanks for the help, and I can't wait to complete the crack!