How would you do this?

[tilite]

Yes, you are ussing the tools correctly

shear- well you have no hope
flow - bingo!

A flow will 'flow' your form along your new backbone perpendicularly inwards at the start and finnish.

example 1> perpendicular to the origin of the new backbone is approximatly 40 degrees from 'flat' so this is where the flow starts from.

example 2> i have taken the same curve used as the new backbone in example 1 and added an additional curve to alow the origin of the new backbone to face vertical. (I hope this is obvious enough - the curve is very short) so i simply joined them to form 1 curve and used that singular curve as my new backbone.


http://img295.echo.cx/img295/9114/flow4be.jpg (http://www.imageshack.us/)

I found that very hard to explain, so if it makes no sense at all please mention it - i will slap myself then rephrase it the best i can.

[edt]
i hope this image explains the additional curve better than the last example.
http://img295.echo.cx/img295/4678/flow3nm.jpg (http://www.imageshack.us)

good luck tell me how it goes!

[andrewjohn81]

if it were me I would just rebuild it, but I'm a big fan of suple geometry since it's easier to edit later. Those surfaces look about right in one direction, but are much more complex than they need to be in the other. I wouldn't use more than 1 span by 3 spans at the most for each of those four surfaces leading up to the cap.

That way you can watch the tangency yourself, and you should be able to manually adjust 8 or 12 cv's without too much hassle. Then you wouldn't have to worry about using the flow commands or anything like that. Since those tools only work some of the time, it's often faster just to do it yourself.

[Azeiku]

So the new backbone in example 2 is actually tangent to the original backbone at the start point and then curves from there? Is that what you were showing? And that is what should keep my base nice and flat?

The only problem there is that my base isn't coplanar. Maybe I should have it normal to the closest to coplanar I can make it at the base of both backbones?


Thanks!

[Rani]

Create half a sphere and place it whener it should end then cut the surface and blend.

Or use Sweep 2 Rails to build the surface the way you want.



If I'm not clear enough then say so and I'll post pics.

[andrewjohn81]

Rani-

that's basically what I was trying to say, but the rails are too complex to edit easily. He needs to rebuild them to be simpler, and all have the same number of points.

[Azeiku]

Okay, I tried blend surfaces making a surface come off of each face tangent to the face. I put a cylinder on the top and it worked great for the the two simple sides but not so good for the others. So, I tired to network surface the other two sides (complex ones that flare out at the bottom to go around the circumfrence of the ring) and that worked but the angles I got were all wacky. So I scrapped that idea.

What I ended up finally doing was what andrewjohn81 suggested. I took the straight up prong and rebuilt them with the rebuild command to simplify them. I ended up having to use 8 as the max value in U or V and 4 as the other. Worked well. I then took my base backbone and original backbone and put points at the same height on them and then moved the control points of each surface using those points as references. That gave me the curve I wanted. Then I went along each edge and moved each point to the corresponding point on the adjacent surface so the surfaces touch each other. Now it looks like this. Was a pain but it looks better.

Thanks for all your help!

[Dimos]

Have you tried the Bend command? It respects the origin point, so your base area will remain as it is, and also the origin point can be placed anywhere on the 3d space. Then you can drag the upper area of your shape to be exactly where you want to be, although I recommend to build the curves/surface from scratch.

[kirisute]

i would create a curve network that would replicate the overall contours of your pillars....extrude a solid from them to the correct width
then use cutting surfaces to trim them into shape...both from front>back and from side views.....
then fillet edges to achieve nice rounded curves where you need 'em.....

[andrewjohn81]

don't you think trying to fillet something to be perfectly round is, well, impossible realistically? I think the way he is going about it now is fine, only that the surfaces may not be truly tangent, at least in the last image. Using fillets you would either have stitching/joining problems, or you would have a small strip between each set of radii that would make it not completely round.
I think he chose the simplest/best path.

[Azeiku]

I did try the bend command but the funny thing is, I'd have to make the prong much longer than it needs to be so I could have enough material there when I bend it. I wanted an S bend in it as well so that'd be somewhat difficult.

I didn't try a large extrude and then do a difference of the areas that I need. It's a neat idea except I usually have difficulties with my boolean operations working properly, not to mention fillet issues with complex surfaces. I did use fillet type techniques on the last time I built this but the way I did it this time left a MUCH cleaner surface than my previous build.

I'm not sure what you mean andrewjohn81 that it won't be tangent. The surfaces seem great with each other. My biggest concern is tangent with the shank portion of the ring (I believe it's red in the picture. The outside of the ring needs to be perfectly tangent and from a render I did yesterday with smooth metal, it seems perfect (to the eye). :-)

Thanks again for all the advice. The difference idea sounds fun too, I may give that a try out of curiousity. I've tried that for other models and it didn't seem to work so well... this seems to be more open though. :-)

Thanks!

[andrewjohn81]

The tangency problem, if there is any, looks to be where each of the four surfaces meet. Any time the isoparms for a sharp corner is a good sign that there may be a tangency problem. If this were a car, that would be a problem, but since it is something much smaller it really doesn't make a difference.

I only said there May be a problem with the tangency, also. If those are trims then there may not be. If they aren't then they probably aren't tangent, but close enough. Once you get a certain size, since the size isn't machineable, the small tangents on a round won't make a difference anyway, right? I'm not a jeweler, so I don't know what kind of machines yall use. I've used some cnc before though, and find that to be true for that.

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