Spinning tops

[Hitch]

Made a little spinning top the other day, a simple little project about 80mm diameter

It does spin okay, but not overly impressed with how long it goes for.

The question, is there some kind of optimum relationship between height, diameter, point angle and so on?

 

[Phil Pascoe]

The best diameter is about 8000 miles................the earth hasn't stopped spinning yet!

 

[Hitch]

The best diameter is about 8000 miles................the earth hasn't stopped spinning yet!

You mean, the earth isn't flat? :shock:

Thinking about it, heavier and bigger it is the better it will work....like a fly wheel, more weight, more energy....?
Looks like i've answered my own question #-o

 

[drillbit]

Immo engineer but of the tops ive made the best style seems tobe bottom heavy and with a nice thin shaft for optimum twist thrust!

A wide flat v shape seems to spin longest. I just part in at right angles to the shaft and cut a v below.

 

[nev]

good looking top, is that one piece of wood painted or made from 'parts'?

looking at this http://www.4physics.com/phy_demo/top/top.html the two things that stop a top spinning are air resistance and slide friction. so you need the pointiest point to reduce the slide friction, and a vacuum :wink:

 

[Hitch]

Right, got it. Balance must be perfect, and launched as straight as possible to avoid any precession....

Perhaps next time I might go for a parallel launching handle too, might make it slightly easier to launch straight.

I did try it dry assembled with the body the other way up, it worked very slightly better, but didn't look right to me.


Its in 3 parts Nev, Body turned on a nice little mandrel, the point and handle turned in a jacobs chuck.

 

[Aled Dafis]

I turn mine in one piece much in the same way as Glenn Lucas

http://m.youtube.com/watch?v=9VRRUv1BrxI

He's a bit quicker than me though!!

Cheers
Aled

 

[woodturnerEric]

the optimum diameter is suposed to be about 6" or 150mm across,acording to what I was reading on a proffessianal turners site,can`t remeber which one though,

Eric.

 

[Harbo]

I made these a couple of years ago for my Granddaughters:

We broke them last week with some over energetic pulling - the stems broke.
Might replace them with some brass rod stems?


Rod

 

[Robbo3]

I turn mine in one piece much in the same way as Glenn Lucas

http://m.youtube.com/watch?v=9VRRUv1BrxI

I wondered why I couldn't view this video. It's for a mobile phone I presume.

The link for the rest of us - http://www.youtube.com/watch?v=9VRRUv1BrxI

Robbo