Posted by James Briggs on December 30, 2003
In Reply to: Not worth a tinker's dam posted by Bill Oetinger on December 30, 2003
: The etymology given for this phrase indicates that it is the solder used by tinkers to mend pewter ware.
: I always understood that the tinker actually had a small device among his tools that he could use to dam up molten solder and hold it in place over a repair. It was this tool that was actually a tinker's dam and not the solder itself. But I have no basis for this conjecture except having read it somewhere, years ago.
If someone doesn't give a tinker's dam (or cuss) the they are reckoned to be completely indifferent to the outcome of an event. Dam (note the lack of a terminal "n") is used today to describe a structure for holding back water; so it was in the days of Tinkers. They used to travel the country earning their livings mending pots and pans and sharpening knives. They would mend the pots by filling the leak on the inside with some clay and then repairing the outside with permanent material. When this was done the clay was discarded. The clay stopper was the tinker's dam. The dam was also known as a cuss. Both were worthless, hence the saying.
An alternative explanation is based on the supposed frequency that tinkers swore - so frequent that the value of their 'damn' was worthless. You choose - I prefer the first explanation.