Hi all,
I just started with MOI 3d...

I wanted to create a "tap" ..
But I don't know how to finish the "lever" to become rounder .. (not straight).

Any idea ?

Regards,

Here the lever :








Here the scene rendered.

I fooled with this a bit. i tried to do a revolve/rail revolve but trying to keep tangency or curvature for a render was tough. So I added the red line to use to trim the end surfaces edges and break them into 2. Then I could run Blend and get a good cap with curvature.






THe other option I thought of was to just extend the sweep out further than the end was required, then just cut it off at the point wanted and run a fillet command on it.

One thing to point out here for you is if you keep your sweep path and profiles all together, it forces a kindof "forced match" that can produce that kindof pinch you have there at the end. Because the path goes beyond the profile and does wierd stuff. Move your profiles out of the bounds of the path and get better results.

Rail Revolve ?

Here's the filet method I mentioned.

....Loft with > 4 Rails/Giude curves...could help :)

Hey Ralf,

We're still waiting for an example/explanation for Loft with > 4 Rails/Guide curves, I'm very interested.

-

Hi Ralf,

> ....Loft with > 4 Rails/Giude curves...could help :)

I see - previously you didn't mention that you wanted 4 guide curves.

In MoI, the Network tool can produce a surface from 4 guide curves, like this:



Just select all 4 curves and run Construct / Network to get that result.

If that's not what you mean by "Loft with guide curves", you're going to need to post an example model or describe it with a bit more detail.

- Michael

Hi didis_be, welcome to MoI and to the forum!

When you have a question about a particular model, can you please also post the 3DM model file as an attachment instead of only screenshots?

That gives people some objects to work with and try things, and makes it much much easier to give specific suggstions.

But generally it's the Fillet tool that you would use to make a sharp edge to be rounded off.

If you want the whole tip to be rounded and not just the edge, one technique that can work well is to model a rounded cap surface and boolean it with your piece, then use Fillet to round off the edges where the cap hits the main body. Please see this previous post for an example:
http://moi3d.com/forum/index.php?webtag=MOI&msg=2909.2

- Michael

Also another possible technique is to model the rounded end as a piece that is slightly separated from the main body and then use the Blend command to fill in some smoothly attaching pieces.

See here for an example:
http://moi3d.com/forum/index.php?webtag=MOI&msg=2221.5

- Michael

There is a great script to add for doing lofts with as many guide curves as you want. It's called CSec and can be downloaded from the MoI Resources page. With this script you can make a whole bunch of guides and then create the sections that you can use to loft with. I love that command. :O

That creates this type of result:

Burr for President :) for CSec, thank you so much...

Hi Burr & Ralf - most of the time CSec is not really needed though, just directly loft the guides with one another using the "Closed" option.

So for example with these 4 guide curves:



Instead of using Csec to set up many sections, just select all 4 and use Loft and hit the "Closed" checkbox, it will make this result:




CSec is just kind of an extra step to go through that is not really needed normally.


You can also draw curves at the ends and use Network as another way too, like this:




If you like the way CSec works, then certainly that's fine, but it will probably take longer than these other ways.

- Michael

Thank you Michael.

I love the CSec and it works as I expect and for me it is no unnecessary extra step. :)

Michael,
I never thought of loft working in that way. Thanks for that. More tools for me.

I still have difficulty in my thought of when the network works on curves and so it is used less by me (although it does produce grat results) You have already given me a good explanation of how it works with the "Longitude/Latitude" curves, but for some reason, it just doesnt equate or sink in.

Possibly some day when I can sit in front of someone who understands it, I can get the jist. If I ever get the chance to see you at a sigraph or something, you can be sure I'll say, "Well, it's me...Can you go over that a bit more in front of me?" :O

I'm sure you cant wait! ha.

Burr

Hi Burr, re: Network - yeah it can take some getting used to since you cannot have just a big pile of curves they have to be arranged into a kind of grid-like layout.

But if you have things set up to do CSec, Loft, or Sweep, you will also be having the same kind of 2-directional layout for those things already as well. So it may not be very far away from what you are already doing...


Another way to think of it aside from "latitude & longitude" lines is to think more about the final result surface.

You're probably getting more used to seeing how a NURBS surface works where the surface is made up of a grid of control points, right?

So when you have that grid of control points there are 2 directions associated with the grid, called the U and V directions. To use the Network command, you need to have 2 sets of curves in the network, one set will become the U curves of the result surface and the other will become the V curves. So you basically need the curves arranged similar to how the surface control point grid of the final result surface will be if that helps explain it in a different way...

- Michael

Hey thats it! Thats much better than the logitudinal thing for me. I get that. One quick question on this to finish. I guess in the past I also was trying to "connect" everything and then "trim" them at the intersection points to make it work. I must have misinterpreted something I saw here in the forum regarding "One particualr case with a curve set. But recently, I have seen the curves from say the Ship hull, where they werent even touching! So kindof baffled me but also prompted me to rethink/look at it.

So, can the 2 diractional curves be "Closed" and "Not interesecting"?. Kindof like the "Loft in 2 directions I think I just heard you say? The ship hull had waterline "closed loops" with the open curve stations. Seems it can be this combo, both closed or neither closed?

Dont spend to big a production on the explanation. The UV thing may have staightened me out. I'll invest some time in network and see if I can incorporate that toolset!

Thanks again.

Hi Burr,

> I guess in the past I also was trying to "connect" everything
> and then "trim" them at the intersection points to make it work.

Actually if your curves form a regular UV grid pattern where they do cross (or come close to crossing) each other, then you can actually skip the trim step because Network will trim off any excess parts automatically.

So for example if you have this:



When you do a Network you will get this with the excess parts being snipped off:




> So, can the 2 diractional curves be "Closed" and "Not interesecting"?.

Yeah, they don't actually have to completely intersect but they need to come at least somewhat close to one another.

If they are too far apart from intersecting it can produce not as good results like stuff may tend to get somewhat extra lumpy. Also if they are too far apart MoI will probably have difficulty figuring out how they are organized into the 2 different U and V sets.

But if they are relatively close to intersecting but not exactly intersecting that is usually ok.


re: "Closed" - yup either the U or V direction or both can be made up of either open or closed curves.

If they are open in one direction and closed in the other, that will be like a cylinder surface, like if you look at these points there is a closed loop in the circular direction and the other direction is a line which is open:



It's also possible for one of the directions to collapse together to come to a single common point, either at one end or both ends. That's something like how a sphere's points are arranged:




Closed in both directions would be similar in layout to a torus (donut) type shape:




But all curves of one set need to be the same, you can't have something like several U direction curves with only one closed and the other U direction ones open. But the U curves can be different in closure than the V curves though like in the cylinder type case.

- Michael

Hi Burr, just another bit of info on Network.

When I say it needs to make a "regular" UV grid what I mean is that every U curve crosses every V curve.

So for instance something like this is not going to work right:




That does not form a single complete grid, for example note that this pair of curves (one from the U direction and the other from the V direction) are not crossing each other:




In a NURBS surface you can't have just one single control point in the corner missing like that, a NURBS surface is made up of the same number of points in every row or column. The same kind of thing applies to Network as well.

- Michael

Ok I'm armed for exploring.

Thanks!