NEED HELP! - NO IDEA WHAT THIS PART IS FOR?!

[giardinm]

So, I have several of these older roller ball kits that required stepped drills. they appear to be PKMONT-RPT (screw on cap roller ball) kits. I have the instructions from psi. (https://www.pennstateind.com/library/PKMONT-RPT&FPT.pdf)

However, the part circled in the picture is not anywhere to be found in that instruction. Every kit has one in it. Anyone have any idea what it is for? Is it a tool? Is it an assembly part? Is it a pen rest? I'm lost.

 

[its_virgil]

It slides inside the plastic retainer and holds the cap in place. The roller ball tip or fountain pen tip fits inside to hold the cap in place. Rather difficult to explain. I hope you get what I'm trying to say.
Don

 

[magpens]

It looks like a leaf spring (4 leaves) that goes inside a cylinder, like the cap of the pen.

When you slide the cap on the leaves compress and hold the cap in place.

You don't separate the leaves. . You "roll" the whole thing into a "cylindrical" form

 

[Seer]

Thats the same piece they use with the Seam Ripper kits now

 

[Dieseldoc]

Found old kit instruction sheet with drawing of ware to install spring clip. See attached.

 

[Dale Allen]

So it is just to centralize the nib section? It looks like the plastic insert acts like a snap-cap pen and that is what keeps the 2 parts together when closed.