We can find some old tsubas that have punchings around the tang hole. Some are originally punched, and some seem to be done later.
Some old tsubas are originally punched around the tang hole. That is done on the obverse side. The work is purposed to get a good fit with handle. The other side must be kept flat to put on habaki there.
On the other hand, when the tang hole is a little bigger than the tang, mount worker punches around the tang hole to make it smaller. This work also is done on the obverse side. The reverse side must be kept flat again.
After 16th century, many tsuba smiths inscribe their signature on the area under the seppa. Usually the signature is put on the obverse side. Then the punching work to make good fit with handle is forgotten.
Signature "Yamashiro-koku ju, Umetada Shigenari"
On the other hand, some tsuba smiths don't like to be damaged his signature by later punching. Such smiths put their signature on the reverse side.
Signature "Shoami, Shigetsugu saku" on the reverse side
Our smith makes the classical styled work around the tang hole sometimes.
