how does one eyeball conical vs parabolic in hornresp?

[freddi]

I goofed when using Jim Bell's Vitavox "Thunderbolt" model and specified PAR rather than Jim's "CON" - ("PAR" gives a pretty/flat sim whereas "CON" a considerable dip)

please explain how to choose the correct segment flares for a model by looking at a drawing of its cross-sections. When does it effectively change to conical?

Thunderbolt has two parallel sides to enclose its fold:

 

[Brian Steele]

If the box has got two parallel sides, then PAR(abolic) is likely the correct option.

 

[freddi]

Thanks Brian - I see on page 3 of a Thunderbolt thread that Jim refined the expansion and used PAR

 

[GM]

If the box has got two parallel sides, then PAR(abolic) is likely the correct option.

Has to be 😉, though the sum of the segments can approximate an expo, etc., flare.

GM

 

[David McBean]

please explain how to choose the correct segment flares for a model by looking at a drawing of its cross-sections.