Raimey, "soft solder" is the standard by which most doubles are joined, including some of the very best guns very high dollar guns in the world. There is no connection to be made with the use of this term and epoxy cements. I don't believe Merkel ever used such a joining method. "Soft solder" refers to the industry standard lead/tin compound, which melts at a relatively low temperature, and cannot be caustic blued. Silver solder compounds actually contain silver, and melt at a higher temperature, and are not attacked by the caustic blue solutions. I have seen "jack-leg" repairs which attempted to use epoxy cements, and have seen scope bases "leveled" up after a poor drilling and tapping job which used epoxy to level and "shim" the poor workmanship, but I would seriously doubt that a company like Merkel would use it, particularly when the standard solder compounds are good performing products and their workmen are already trained in using them.
