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Full Version: MASTER MODELLERS Modelling Approach

From: AlexPolo
13 Sep 2017   [#1]
Hi all,

Trying to create a shape similar to this have had various levels of success wondering if any Master Modellers have any pearls of wisdom on approach methods.

Have tried blended lofts and subD skins


Image Attachments:
Mobius.jpg 


From: bemfarmer
13 Sep 2017   [#2] In reply to [#1]
Hi AlexPolo

I've seen this art piece in the past, but never figured out how to do it.
A few years ago I saw it with a red face, and another color face, I think on an artist's site.
There were a few more view angles.

This recent post may be of help. The basic shape of the holes is that of parabolic cyclide, two parabolas
with vertices passing through each others focus, with different size circles ( or spheres) centered on them, and lofted/swept.
http://moi3d.com/forum/index.php?webtag=MOI&msg=8576.5

Do you have a link to the page with the art?

- Brian
From: AlexPolo
13 Sep 2017   [#3]
Hi Brian,

Thanks for link will delve into it here is link to artists site.

http://www.bridgesmathart.org/art-exhibits/jmm09/friedman.html
From: bemfarmer
13 Sep 2017   [#4] In reply to [#3]
There are 3+ views of the carved 10" X 6" limestone, of carved wood here:
http://breezyhillturning.com/Minimal-surfaces/minimal-surface-turnings.html

Copy of paper by professor Nat Friedman:
http://math.unipa.it/~grim/21_project/21_charlotte_FriedmanPaperEdit.pdf

Note that the soap film, figure 3d, has two holes with two surfaces, and the same trefoil knot is shown in figure 7c,
as a two hole knot, which is formed by manipulating the one hole, one surface, trefoil knot of figure 7a.

I have not found a surface evolver model yet.

- Brian
From: bemfarmer
13 Sep 2017   [#5] In reply to [#4]
There is a tinfoil model of the knot here, as well as 1/4" copper wire.
http://t.archive.bridgesmathart.org/1998/bridges1998-139.pdf

So making such a trefoil knot in wire, and dipping it in soap and glycerin, popping the two holes,
should give a physical model...

Surface evolver is the other option...

- Brian
From: bemfarmer
14 Sep 2017   [#6] In reply to [#5]
The program for surface evolver, for a different sculpture, between an unknot and a trefoil, is explained here:
https://www.thingiverse.com/thing:1559227

- Brian
From: amur (STEFAN)
14 Sep 2017   [#7]
Looks like a mirrored version of Jotero's Yin Yang. :-)

http://moi3d.com/forum/index.php?webtag=MOI&msg=5529.1



Regards
Stefan

Image Attachments:
Jotero's Yin Yang.jpg 


From: mkdm
14 Sep 2017   [#8] In reply to [#7]
Hi Stefan!

Wanderful model! Could you post the 3dm ?

Thanks.
From: amur (STEFAN)
14 Sep 2017   [#9] In reply to [#8]
Sorry Marco, better not...

Best regards
Stefan
From: mkdm
14 Sep 2017   [#10] In reply to [#9]
OK. No problem.

Bye.
From: bemfarmer
14 Sep 2017   [#11]
That is the one I half remembered, only 5 years ago!
Time to try again...
As far as I know, there is not a .3dm available.
- Brian

The front view and the left view are symmetrical.
From: AlexPolo
14 Sep 2017   [#12]
Hi All,

Thanks for the leads cant believe the historical trail needles in a haystack falling in the same pile - MOI a great forum with a diverse range talents!

Will digest posts contained.

Best regards
From: bemfarmer
14 Sep 2017   [#13] In reply to [#12]
IMHO, the "yin-yang" is a seifert minimal surface on a trefoil knot.
Using the flat crossing knot diagram of the trefoil knot, showing two holes, the "braid" type,
there is a procedure to make a seifert surface by replacing the crossings by bands rotated 90 degrees.
Unrotating the central band orients the two holes to 90 degrees, and the flat surface becomes 3D.

- Brian