Summary

Spinning top with weight mainly pushed to the edge, rather than the centre as is more normal, so gyroscopic effects give this a very stable spin. The top is spoked to further reduce central weight.

Instructions

Spin by holding the edges as you would spin a plate or bottle, or put your slender fingers in the gaps between the spokes and twist. I intend to design a proper handle to clip into the top of it, but it works okay as it is.

I have managed reasonable spins on a tablecloth as well as a carpet with a rounded pivot -- it seems to work a bit better than other spinning tops on softer surfaces.

v2 adds a little handle (or alternate pivot point), which should slot into the bottom/top of the spinning top.

v3 is again a single print with an internal grip. It's a little bit too small for adult hands (so print at 1.5x if you want thumb/finger space), but should be fine for little kids.

v4 has a tube finger grip with a wider space for thick fingers. It also includes rotated ring supports that should act as air fins to stabilise the top (and give it a bit of lift). There are two STL models, one to lift on clockwise turns (_RH), and one to lift on anti-clockwise turns (_LH).

v5 is inner-ring free, has a thicker outer ring, and exploits a 45 degree angle upwards from the centre to reduce spinning top height. A rotate-extrude in CGAL wouldn't work for me, so I've compromised with a spider-like 8-way spoking.

v6 tries to do away with the finger grip entirely, using finger rings instead. I ended up welding a spare handle onto the top, because I made the rings too small (the STL file has been updated to account for this).

v7 also tries to do away with the finger grip entirely, but uses a bar instead of rings.

v8 returns to the finger grip, after a discovery on use that the finger grip provides much more turning power. I have now worked out how to do a properly rotated polygon. The ring is also modified to be a slice of a hollow sphere that is centred on the pivot point.

v9 is back to basics, but includes a split print with a M6 screw thread

v10 changes to an M10 screw thread, and leaves the axle customisations to the user. See M10 Toolkit for things to put inside the axle hole. It works well with threaded rod and an end cap.

v11 uses a non-spoked bottom with periodic holes in it.

2 Minute Spin

            <p class="detail-caption">M10-Threaded spinning top with 60mm flat threaded rod and end cap. </p>            <p class="detail-video"><iframe src="//www.youtube.com/embed/7ThT-oBV91I" frameborder="0" allowfullscreen></iframe></p>            <p class="detail-caption">Spinning Top Stopped by a Cat</p>

Flat Spinning Top