Tailstock in the way...

[J-G]

It's a fun subject for those who are so inclined! (I happen to have a degree in maths so quite enjoy thinking about it).

Agreed - it was my interest in the mathematics of Conic sections that started me thinking about how to turn Elliptical work.

As for semantics between oval and ellipse ... my guess is that folk refer to oval as its a more readily understood concept than 'ellipse' ...the latter being typically defined by a mathematical equation ...and maths often has a habit of making folks fall asleep!

It's good to see that there is a reference to the correct nomenclature on the first page of the Volmer web-site.

(by way of illustration of irrational ambition .. I have in mind a set of scaled nested oval bowls to try to represent the planetary orbits in our solar system...which..when reflected on... is non-trivial without excessive simplification!... maybe I'll develop the skills and creativity to do this nicely one day!)

Ah... we are obviously of a kindred spirit! - - - I'm in the process of building an Orrery so have done a lot of research on how to handle the scale. Only Mercury and Pluto (Ok dwarf-planet!) have a high enough eccentricity (M = 0.2056, P= 0.2553) to make any visible difference on a manageable model.

I'd now normally list the relative model sizes of the orbits but I can feel the reader nodding off ! :lol:

 

[dcmguy]

Hi J-G

Yeah..Volmer was no slouch... I think he was a professor ..but not 100% clear.

As for conic sections... diverting significantly from topic here ...but I've been quite interested in trying to apply the maths relating to the 2-dimensional effect of passing a notional hollow cone through a notional 2-D plane ... and then trying to extend everything by a dimension to form a mathematical framework for gravitational 'events' (such as 'big-bang" theory). No useful outcomes yet, funnily enough.

More prosaically, for a 'nested' solar orbital suite I was thinking of using natural logs to 'normalise' relative distance but also looking to define an outer bound as Halley's Comet ...very much a hybrid of definition and decorative opportunity!

Coming back on topic ... when you turn ellipses, may I ask which lathe (assuming not homemade) you use and where you stand (for the inner turning) relative to the bed?

cheers

 

[J-G]

New thread started...