Can someone PLEASE tell me how to build this ring from a network.
It a simple shape but I just cant get the network command working.
There must be some nuances about how curves connect because I get alot of failures.
I ended up building this in a roundabout way using cuts and lofts and blends but I need more control and the only way I can think of is to network outlines.
Any suggestions would be appreciated
Ive included a sample file
ps- disregard the wave in the middle of the band..its actually a split ring(i know how to split it) but I need the whole general shape

I did a sweep of the two "D" shapes, with the blue circle as a rail.
Looks like you may have Projected an ellipse, and lofted the projected ellipse with the "eye" circle.

Hi Stav - in order for Network to function, the curves have to be unwrappable to a regular 2D flattened grid. Think of this as similar to how a globe unwraps to lines of latitude and longitude on a flat map. All the lines of "latitude" must cross all the lines of "longitude", you can't have just separate little pieces of curves here and there that are not part of the regular grid layout.

Similarly if you've got a closed curve for one curve in one of the latitude or longitude lines, the other curves that are part of that direction of the grid must be closed as well.

So some of the things about your layout that breaks these requirements is you've got a closed curve here:



But then the other curve that should be a partner to that one (one of the same set of either longitude or latitude) is not closed, and does not cross the same extent of the other set of curves:




So you'd need to have a closed curve to match the other closed curve, then maybe once the network is complete you could slice off the end rather than trying to build to the sliced planar end directly in the network itself.

Also another problem is your curves are fragmented into little separate pieces instead of being all joined together into long segments to define full sections of the grid, like for example these little pieces are individually selectable:


One single line of "latitude" or "longitude" must be one long joined curve.

Check out some of these ring tutorials for some construction tips, these are from the Resources page on the wiki:

http://moi3d.com/forum/index.php?webtag=MOI&msg=284.1
http://moi3d.com/forum/index.php?webtag=MOI&msg=510.5
http://moi3d.com/forum/index.php?webtag=MOI&msg=623.1
http://moi3d.com/forum/index.php?webtag=MOI&msg=556.1
http://moi3d.com/forum/index.php?webtag=MOI&msg=538.6
http://moi3d.com/forum/index.php?webtag=MOI&msg=536.1
http://moi3d.com/forum/index.php?webtag=MOI&msg=1175.3
http://moi3d.com/forum/index.php?webtag=MOI&msg=1175.5

Hope this explains some of what you've been running into.

- Michael

Hi Stavros,

Like Brian mentions sweep would be the way to go, and it'll have history attached so you can fine tune the shape dynamically, diameter as well as profile, however once you do another operation on it, e.g. trim all history will be lost but with the amount of features on the ring so far it wouldn't be a problem just to undo a couple of steps and tweak away.






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Hi Stav, also it can be problematic to try and do a toroidal type network with only 2 cross sections in each direction.

The way Network functions is sort of like doing a loft in 2 simultaneous directions, and a closed loft between only 2 sections is not very well defined, it sort of gets flattened down.

So you may need 4 stations for something like this to get done with Network. For a lighter number of sections with a toroidal type layout, sweep can tend to be better than Network.


Another problem area for your network setup are your curves have some little tiny sharp cornered segments in them, like here:





These kinds of little segmented shapes in the curves will become long slivery sharp surface bands stretching the width of the network result as well.

- Michael

Hi Stav, also attached here is an example of the kind of layout you would need in order to do a network on this.

But I'd think that probably Sweep would be better for you anyway though, the way that sweep works is by sliding the profile curves along the rails, because of the way it works the shape of the profile curve is rather more rigidly maintained throughout the generated surface than Network.

Network is sort of more like putting a membrane on the wires, the generated surface will have a certain element of slackness to it when it is in areas in between profile curves.

- Michael

Another networkable sample attached here - this time with 4 curves in both directions, that controls the shape a bit more, not as much slackness in it.

- Michael

And then one way to introduce the flat piece is to take your full ring that was initially built with it all smooth and not flat end at all, like this:



Then draw in a line in the top view, and use it as the cutting object in Boolean difference or Trim to slice a piece off:



That will now get you a flat part, if you wanted to control the exact outline of that flat area more, you could draw it in with some space around it:



Then select the edges and use use Construct > Blend to put in a smooth connecting piece:






When you have a shape that looks like a continuous smooth thing but then that comes to a sudden end or change in shape, it can be good to create by making a larger smooth piece initially and then cut some of that smooth piece off rather than trying to construct the initial surface right directly to the sudden change spot itself...

- Michael