The traditional method of fixing the hammer on the handle is wedging. Over time, however, the knot loosened and it is necessary to change the wedge or pen.
I suggest to fix a clogged wedge with a screw or rivet passed through the bore in the sidewall of the through hole.
Recommend to read
AEROBATICS “FLYING WING”
By the mid 30-ies of the aircraft type "flying wing" was quite true to their name — they were flying. In our country, in Germany, England, Switzerland, designers and innovators to pilots...
IF THERE IS NO AUTOMATION
Most modern refrigerators include automatic defrosting system. In the old it is not. So every time you have to wait until melt all the ice of the freezer, and periodically pour the water...