Hi,
is it possible to have an elipse centre then top then tan and pick a line ?
click A for centre, then B for top then line C for tan to.
A is not critical, can be up or down a bit on it.
B is, and C also plays a part !
so one could do A then C then click when happy with size and get C.
I see no tool to do so in the elipse set of tools.
ELIPSE CENTRE TOP TAN.3dm (32.8 KB)
Cheers
Steve
Hi,
steps then are
??
Steve
construct the lines as shown, then draw a 2-point circle with the height you need, then scale1D using point 1(origin), 2(reference), 3(target)
using End and Intersection Osnap
You might try the Conic command.
To make the curve pick point B then C then the intersection of B and C. After that you can select the shape of the curve.
The result curve will always be tangent to lines B and C.
Hi,
Conic seems so simple, however as I move the conic about I see shapes that couldnt be an elipse , or could they ?
is that a quarter circle as such ?
Gijs de Zwart method uses a circle so has to be one.
Steve
The shape you end up with may or may not be an elipse.
It depends on the Rho value you choose in the final step. If you are trying to match a reference elliptical shape it works pretty well.
http://www.viewmold.com/ug_html_files/modeling/crv_2pt_anc.html
Is there a specific reason it needs to be a mathematically accurate ellipse?
If not, draw a degree 3 curve using End and Near osnaps.
Start the curve at end point B. Place the second point using near and about half way down towards the guide curve intersection.
Third point about halfway between the guide curve intersection and point C.
Fourth point at C.
Turn on the new curve’s control points and adjust the inner two points along the guide curves to suit.
