H-15 variant: Does anyone know how this pommel attachment works?

[screened porch]

I don't think it's a home workshop repair.

Is it a hollow rivet going through a narrow keyway and expanding into a larger cavity?

 

[tiguy7]

Looks like a pop rivet. Hope it’s stainless and not Aluminum.

 

[screened porch]

Looks like a pop rivet. Hope it’s stainless and not Aluminum.

It also looks like the sort of hollow rivet they attach shovels to handles with, or Colonial and Imperial covered with their false bolsters. It appears to be magnetic, but it's awfully close to the obviously magnetic tang, so it's hard to be sure.
The rivet is also one reason I almost didn't buy the knife, but I saw the same arrangement on an H-15 online so thought it must be ok.

 

[tiguy7]

It also looks like the sort of hollow rivet they attach shovels to handles with, or Colonial and Imperial covered with their false bolsters. It appears to be magnetic, but it's awfully close to the obviously magnetic tang, so it's hard to be sure.
The rivet is also one reason I almost didn't buy the knife, but I saw the same arrangement on an H-15 online so thought it must be ok.

I am not sure why your tang might be magnetic. Materials that are attracted to magnets are said to exhibit Ferromagnetism. A magnet will pick up Ferromagnetic paper clips.

 

[screened porch]

My tang wouldn't be made of steel?

I am not sure why your tang might be magnetic. Materials that are attracted to magnets are said to exhibit Ferromagnetism. A magnet will pick up Ferromagnetic paper clips.

This is from a Codger_64 contribution to a 14-year old thread by a banned user. Looks like you called it with the pop-rivets.

As a point of interest, compare the attachment means for the "Caps" (pommels) of your varients. You will see three or four different ones, including one drilled and pop-riveted, one smooth peened, and one peened with a drift punch. I don't have enough datable examples of these knives to do a proper survey of the method/pattern/dates.

My Imperial and my other Schrade both appear to be drilled through the pommel and pinned through the tang like a Mark II Navy.
Or (duh) the one above on the left might be peened with a drift punch, and the one on the right might be smooth-peened.