Catenary curve metric

[Roger Caffin]

Lost in the woods . . .
PM me with your email addy and I will send it to you.
I have notified BPL as well.

Cheers

[Sam Farrington]

Steven,

Am not sure you need more than a shallow hoop.   Have not been able to find it, but several years ago some engineers who were members presented mathematical proofs that the formulas for catenary curves were almost identical to those for parabolic curves; that is, the curve you get when bending the ends of a flexible tent pole from end to end.  Or you can use any flexible rod, like the small diameter fiberglass or plastic ones sold in hardware and job lot stores.  Once the ends of the rod are connected by a cord and adjusted to match the length of the seam, you have a curve than can be transferred to the fabric.  There is one catch.  The deflection of the seam will be greater than the deflection of the curve, because on the seam there are two curves, one on each side of the seam.  So the deflection of the bent rod should be much less than the deflection you want on the seam.

Wish I had the thread with the math, but have not been able to find it.  If  I’m wrong about this, would love to hear about it.  Those engineer/mathematicians had me totally convinced.

[steven k]

Thx!

[Sam Farrington]

SK, you can reach Roger at:  [email protected].

[Roger Caffin]

Yup

[Bill in Roswell]

If you’re looking for vertical cat cut info, check out some DIY sail making sites. I’ve sailed most of my life where cat cuts were the norm. You can gain a load of info on such sites.

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