Turns out you can use CorelDraw to reverse engineer the parts to a conic section model.
The files are here, please help yourself. I cut ours out of 1/8″ wood so the slots are that size – you may need to adjust.
If you want a model we may be able to send you one for free. Please fill out this form and we will get back to you.
8.5×11 Printable PDF (glue to cardstock instead of wood and cut out)
To make from “scratch”:
Start with an isosceles triangle and then draw lines – across for circle, parallel to a side for the midline of the parabola, across at angle for ellipse and vertical (or not parallel to a side) for the hyperbola.
Next use those lines to find the dimensions of the conic section pieces – diameter of the circle, the long and short axis for ellipse (use the chord at the base located a distance equal to the distance of the center of the ellipse to the midline of the triangle, parabola height (length of line) and width which is the chord where it intersects the base circle, and similarly for the hyperbola.)
Using this sequence we made a pointier version as well in PDF 8.5 x 11
I made a few extras!
Here’s a Cricut and a foam version posted to twitter by Mark Kaerscher
And a 3d Printed model by MathHappens board member Alex Siegel: