Most of time since learning to tie the monkey's fist knot, I've just used my fingers on one hand to hold a core for the fist instead of a jig, and loosely tied the knot with the other hand before tightening it up, which can sometimes be awkward and get out of sorts to the point where I have to untie the work and start over. Remember to take your time and gradually tighten the knot up.
The Maxi-Monkey Fist did well keeping the wraps of the fist lined up as I tied, and left room to continue wrapping when changing directions with the turns. Different sized cores may fit loosely or tight, depending on the size of each, between the zinc plated steel rods that screw into the holes that are drilled and tapped in the aluminum base, which is said to work with cores sized from 5/8" up to 2 1/4". A golfball is shown in the jig next to the tied monkey's fist in one of my photos and the naked cue ball in another.
Years ago I had made a homemade coat hanger jig to help with tying paracord monkey's fists, just like one I'd seen a photo of online, to try with covering ball bearings, wooden balls, and glass marble cores. I've even used a paper clip for a jig when tying around a plastic 6mm glow-in-the-dark BB, with 0.9mm diameter string, after repeated fails and aggravation with keeping things in order without it at the time.
I bought this neck knife to try out some different handle wraps. I've been trying to use up some scrap lengths of cord that I've been holding onto after finishing other projects resulting in a tangled multi-colored pile. I usually try to save anything that I can still use for tying a zipper pull, short fob, or wrist lanyard, with paracord or 0.9mm string and several sizes in between.
glow rope that I applied to the fixed blade handle with a long 2 bight Turk's head knot(13 lead 2 bight), doubled, then added in a pineapple knot interweave with the glow-in-the-dark cord, having enough to wrap some around the sheath and finish with a safety break-away neck lanyard.
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