The literature about how the split jaw posts were manufactured for New house traps during WW 1 1917-1919 is lacking. The posts appear to be stamped. I have come to the conclusion the post were stamped out as one piece rather than two for the following observations. The best way to achieve a consistent post was made possible by stamping both sides as one piece with jaw rivet hole made on the original stamp then applying pressure to the center of the blank post and folding it so the rivet holes align and crimping it together in two places, probably while hot and compressing the shoulder to form a square that fits in the square hole on the base of the trap, the other crimp was higher up to flare both sides of the post to receive the jaw ends. Then a die was used to add the treads to finish the post. Under a magnifying glass one can see a line at the shoulder extending down to the threads but at the very bottom of the threads there is no separation one would expect if it were two separate pieces. Not sure if this make sense
Any thoughts on this?

Is it possible that when the threads were cut and the metal was reformed that it made the seam disappear?
One thing I notice is the end of a split jaw post there seems to be a parallel ridge? Possible 2 pieces?
Good topic to bring up, thanks

I talked to a old school machinist friend and he thought my scenario seemed logical and would be the way he would make them. I looked at all the split post traps I have and they all look like the the post on the right in your picture which looks like it was bent as one piece and not two separate pieces, but not sure.

Nice to wake this site up, how'd you get the nuts off them? I've had the worse luck with them,they might not start out as two pieces but when I'm done they are

I bought a big box of trap parts a couple years ago and there were a couple sets of #4 jaws with split posts.

Always interesting to figure out how they did things.

You want a real mind bender look at the small sized kenwood swivels on the number 0-4 sized traps and tell us how they got those together?

I think I figured it out but it took me years to figure it out.
Simplicity and what they had to work for tools will give you the answers.

Here is your answer on the split post. From Tom Parr's collection.

Thanks for the lesson Dean, I hope to experience Tom's collection this coming June,

Thanks Dean,

It's nice to learn my assumptions were correct.

See you in June.