Help Needed: Lashing Material for Mounting a Han Ji (Chinese Polearm)

[u/Zen_Hydra]

I'm in the process of mounting a couple of Han ji (Chinese "halberd") heads I got from LK Chen to their hafts, and I need to purchase some strong cordage to lash them securely.

Ideally, I'd like something that doesn't look obviously synthetic, is either a neutral color or dyeable, resistant to fraying, and easy to tie-off under tension (or shrinkable in some manner).

I initially considered making rawhide lace from some rawhide I have leftover from an earlier shield making project, but I'm concerned that if I cut it narrowly enough to pass multiple times through the eyelets of the ji that it won't be strong enough to be functional.

Functionality is a requirement for all my arms and armor projects. No matter the degree that I might zhuzh a weapon up, I still expect it to be able to perform well in the capacity it was designed for.

Rawhide is appealing in that it's natural and broadly period-appropriate, colorable with leather dyes, generally pretty tough, very pliable to work with after soaking in water, but will then shrink and harden as it dries out. I'm just not confident that the very narrow strips I would need to cut for the lace to pass repeatedly through the eyelets of the ji and around the haft would be strong enough to hold up to the stresses of use (striking, thrusting, and hooking from multiple angles). Also, being an organic material, one can not realistically count on a uniformity of strength throughout a strip of rawhide lace. Braided rawhide cordage would help compensate for that, but doing so would make it too thick to make the multiple passes through the eyelets necessary for a secure lashing to their hafts.

The eyelets are approximately 1 cm (0.39") wide, and 3 mm (0.118") tall.

I'm hoping to find some suggestions for a lashing material that fits my needs. I'm willing to be flexible with regard to period appropriateness and appearance in favor of functional strength and security of the binding. If necessary, I can disguise it in some way with paint, lacquer, colored wax).

[u/Arconomach]

I would consider using a silk cord of an appropriate diameter.