Intro: The PVC Nunchaku
This years halloween costume was Michelangelo of Teenage Mutant Ninja Turtle fame ... another full body costume with props - functional nunchaku, a 14" pizza with removable slice, and a manhole cover. Because seriously ... what's more exhilarating than wearing a costume with limited mobility, even less visibility, AND onboard weapons within a child's reach? Add a bowl of candy for the victor to that equation and you have yourself a grade school thunderdome scenario.
These are NOT regulation nunchaku - is that even a thing?. They are props ... constructed of plastic, too light, and the chain (also plastic) is probably way too long. That being said ... the cartoon reference pictures had 7 links, so 7 links it had to be.
Step 1: Fabricating the End Caps
Standard PVC caps could be used, which would be quicker and easier, but it wouldn't match the reference pictures, and I like to take the road less traveled - the one that takes forever and is full of rocks. 3/4" PVC couplers have the desired shape, but the ends are wide open, so we have to close them in on our own.
First order of business was to sand off the raised letters on the end, as well as the odd bump on the side. I used the oscillating belt sander for this operation and it made quick work of the offensive nubs [Fig. 1-2].
I have several offcuts of 1/2" PVC sheeting from home improvement projects, which seemed perfect for capping the couplers. I ran the faces through the drum sander to remove the shiny finish and rough up the surface [Fig. 3]. I doubt that was necessary since PVC cement is solvent based and actually softens the plastic to fuse parts together. PVC cement was spread across the 1/2" sheet and then eight couplers placed in the plastic sludge. A piece of plywood and weights were added for clamping pressure and left to cure for an hour [Fig. 4-6].
Side Note: PVC sheeting and trim board is good stuff. It can be shaped and cut with standard woodworking tools, accepts paint, and is lightweight. I've used it to make wearable Scissorhands, as well as a Buffy the Vampire Slayer Scythe (Bardiche).
The octuplets were separated using the bandsaw. I trimmed close to the face of the couplers, but made sure not to cut into them. To flush up the cut, I stuck each coupler on a length of PVC pipe and took it to back to the belt sander. While I was at it, I freehanded a chamfer around the edge [Fig. 7-10].
Step 2: Fabricating the Swivels
Time to make these chucks swivel!!
I marked the center of each end cap using my shop made center finder and drilled a 1/4" hole with a brad point bit at the drill press [Fig. 1-3].
Hardware roll call for each swivel end is as follows: 1/4" - 20 eye bolt, two fender washer, and a 1/4" - 20 lock nut. The washers keep the eyebolt and lock nuts from digging into the 1/2" PVC material and just helps everything function smoother overall [Fig. 4-6].
I glued the external washer to the PVC with Gorilla glue and used the bolt and washer as a clamp. Masking tape was added to help contain any foam out of the glue [Fig. 7].
Step 3: Attaching the Chain
The toughest part of this build was attaching the chain. I did my best not to mar the surface of the eyebolts as I pried them open to attach the plastic chain, but it just wasn't meant to be. I called upon both terry cloth and 1/8" foam, but neither could withstand the assault brought forth by channel locks and vise grips.
Once I had both ends of the chain attached (to separate eyebolts), I covered my destructive tracks with a Dremel and sanding drum.
Step 4: Assembly
Traditionally, the branch lengths correspond to the length of your forearm, from the elbow to the articulation of the wrist ... for me that required the 3/4" PVC pipe to be cut to 8 7/8". Results may (will) vary.
The length of ropes or chains is very variable. Usually, it is one to two centimeters more than the length of the palm of the hand. That makes an average of 12 centimeters for an adult. As mentioned before, I went with 7 chain links in order to remain compliant with reference photos.
Note: I acquired dimension information HERE.
Assembly started with reassembly of the swiveling end caps. I tightened the lock nuts to the point where there was not tilting slop with the eyebolt, but it could still spin freely. Once all four of those were dialed in, I attached the end caps to the pipes with PVC cement.
Step 5: Painting
The Nickelodeon version depicts the nunchaku ends as being a yellowish gold, but I'm not really a fan of that color. Also, all stores were closed at this point and I had an aged copper color in my paint cabinet. It's supposed to be reminiscent of a tarnished penny.
After masking off the eyebolts and chain, I sprayed two coats of plastic primer and three coats of paint.
Step 6: Vinyl Wrapping
The Nickelodeon version also depicts the nunchaku as having a more intricate handle wrap, but this is a prop and I was on a time crunch ... so vinyl was the answer.
Note: I REALLY would prefer and wanted to try the decorative wrapping.
I cut an appropriate patch of vinyl, coated the mating surfaces with Barge, let the cement tack up, and joined the two surfaces for eternity.
Step 7: Glamour Shots
That's all she wrote ... functional nunchucks to be used against you by the adolescent fiends who want to procure the entirety of your candy cache.
They spin ... they are appropriately sized ... and they look pretty good.
You could easily replace the plastic chain with paracord or even real chain if you prefer that look. Another option would be to eliminate the eyebolt swivel ends altogether and just use paracord with the ends knotted inside the PVC.