Name: Make a pocket rocket plumbus with spinning hurricane balls! | Videos | Gan Jing World
Uploaded: 2023-12-01T16:24:13.957Z
Duration: 14 min 26 s
Description: Some of you may be wondering what a plumbus can or will do. This video seeks to explore those questions. ***** A few construction points that are a bit too es... | Videos | Gan Jing World

pocket83

https://video5-us-west.cloudokyo.cloud/video/v6/a3/d8/33/a3d833d7-22cc-466d-89cd-30db807a2ddb/master.m3u8

Some of you may be wondering what a plumbus can or will do. This video seeks to explore those questions.

*****

A few construction points that are a bit too esoteric for the video~

-Symmetry pro-tip: each cluster should be made using identical balls. Golf ball brands seem to have some mild variance to their masses. Better balanced clusters spin more smoothly. I wish I would've thought of that earlier, but I use found balls anyhow, so beggars can't be choosers! I'm lucky to ever find four of a kind.

-A cotton pull string seems to work better. The problem with making one is that you will have to twist the rope yourself into a size that's suitable. Mine was made from three lengths of cotton twine. I used a rope machine (that I made), but a 40" piece of rope could be twisted, at least in theory, by using some clamps/weights/tape to just hand twist the rope. The forces at work in such a small rope are relatively mild, so it can certainly be done, and cotton twine is cheap. What makes the cotton work so well? Well, aside from its smooth and quiet operation, which lends itself to a tactile pleasure, cotton rope can also be stiffened on the end with epoxy. Cotton fibers will readily imbibe liquid, so by covering the last 5mm of your rope with epoxy, you can add a rigid section to the end of the pull rope (kind of like what a shoelace has), which will make it much faster and easier to insert into the launcher. I didn't actually dip the end; I instead dripped a tiny glob of the warm glue on to a length of the rope, and then I cut through the center of the hard spot after it had cured.
     
-Using epoxy to fasten the tetrahedral golf ball cluster together can be a messy disaster. I didn't film it because I had to work too quickly to be bothered. Be sure that all of your parts are ready to go, because you will have just enough time to get to all six connections and all six of their respective holes. Remember that a heat gun will make epoxy become runny, which helps it to spread faster. There will be squeeze out, but it is manageable with this trick: baby powder. Apply it liberally as soon as all of the parts have been pressed together. The mess will no longer spread, but now there's clean-up: toothpicks and a coat-hanger needle tool will easily scrape away the little squeeze-out globules that have been encapsulated and rendered harmless by the powder. Keep picking at the details and pressing in on the connections for around five minutes, and don't become overwhelmed, because as long as you've used the baby powder, you have this completely under your control. I hope this was a fun one for you. Thanks for reading.


*****
Music: 

"Galway" Kevin MacLeod (incompetech.com)
Licensed under Creative Commons: By Attribution 3.0 License
http://creativecommons.org/licenses/by/3.0/