This tool is a Soundboard Repair Tool.
It opens up a perfect "V" joint of proper depth, trims the wooden shim after it is glued and scrapes it smooth.
Made of high quality tool steel that is lacquered.
The Blade is 1" wide and overall tool length is 9-1/2" long.

WHAT IT'S USED FOR:

Over time a piano's wooden soundboard can develop thin cracks along the grain, which buzz and lose tone.
To fix it, technicians "shim" the crack: then glue in a thin strip of spruce.
The shimming chisel is the specialized tool made for that job.