I'm having a great deal of trouble figuring out how to transform an object to bend a tubular portion to follow a profile.

I'm trying to make something that looks like the attached .stl

So far I've got the shape, but straight, as in the attached .3dm

How do I bend the conical portion of such an object to curve and take a 45-degree axial bend, while leaving the normal circular cross-section?

(MOI needs a manual so badly)

Hi Rick, you could use the Flow command which is new in v3 to apply bending on a shape.

It maps between a base curve (or base surface) and a target curve or surface. In this case you can try drawing a line as the base curve running right down the middle of your straight shape, and draw a bent curve as the target for what you want to map onto. Then select your object that you want to deform, run Transform > Deform > Flow, at the prompts pick your base curve and target curve and that will then generate a bent object.

See here for an example:
http://moi3d.com/forum/index.php?webtag=MOI&msg=5097.2


> (MOI needs a manual so badly)

There is a manual, you can push F1 to pull it up locally or see it online here:
http://moi3d.com/2.0/docs/moi_help.htm

It does not cover Flow yet though since that's new for v3 and v3 is still not finished yet. The updates to the manual for new v3 functions will happen at the very end of the v3 beta cycle.

- Michael

Thanks - that's exactly what I was looking for. Any way to make the deformation "live", so I could manipulate the target curve and see the results in real time?

(MOI's a great product, when one can puzzle it out.)

Here is a try, using png image captured from STL viewer "GLC_Player."
The view is sized to approximate the same size as the .3dm
For the Flow target curve, the center bent curve was made using Blend, with the green helper lines.

Created center line for the .3dm to use for the flow baseline.
The lengths of the two curve lines were not quite the same. Could have used some kind of scaling perhaps.
Used the stretch checkbox in flow.
Used UnwrapCurve for lengths.

Your .3dm appears to be thicker than the .stl.

I did the same thing, and had a similar result. One anomaly I noticed is that the semi-spherical cap comes out asymmetrical - it bulges up above the center line. The Object does appear to wind up circular normal to the axis, though, so I'll just cut off the cap, bend the truncated cone, and paste the 45-degree-rotated cap back on.

Thanks for the help. This will become an ergonomic pommel product for sport fencing.

Hi Rick,

> Any way to make the deformation "live", so I could manipulate the target curve
> and see the results in real time?

Yup, it's possible to do that using history. Do the Flow one time and make sure to not enable "Delete input objects". Then select the object and run Edit > History and click "Enable update" button. Now that history updates have been enabled on that object result, you can then edit the target curve and the deformed result will update as you move the target curve control points around.

- Michael

Wow!

Hi Michael
Can the history update be enabled in the moi.ini for flow , thats brilliant , you learn something new everyday in here.
I would love it on ArrayCurve also like mirror or sweep (or is this too resource hungry), I often array diamond models to a profile curve but with any changes to it I have to delete them and re array them.
thanks
shayne

Hi shayne,

> Can the history update be enabled in the moi.ini for flow

At the moment there isn't any method set up to alter the defaults for which commands have history on by default or off by default, I do plan on adding a setting for controlling that though.


> I would love it on ArrayCurve also like mirror or sweep (or is this too resource hungry)

I ran into some problems with the way history works on arrayed items, because the history information is stored on each generated object, when doing an array with a lot of items it caused a lot of file size bloat. So for now history is forced off on array because of that. In the future I want to rework how history is stored so it's stored more in one central spot rather than attached to the output objects.

- Michael

I hate to say it, but I have been completely unsuccessful with Flow, on both 2.5.2 and the Nov. beta.

I've attached images from both versions.

- I can't get MOI 2.5.2 to follow the full target curve. It comes up too short, and with an angled base, while the target curve ends in a vertical line segment.

- If I use Stretch, 2.5.2 destroys the object.

- Using the Nov. beta, same issues - without Stretch, it ignores the straight bottom end of the target line, and then,

- Nov. beta Stretch completely munches the object even worse.

These ongoing issues are preventing me from bringing a product to market, and I cannot find any way to make MOI do what it is supposed to capable of. I've been hung up on this not working for quite a while, and I'm sure it is my lack of understanding, but I'm totally stalled.

Any ideas or fixes?

Here's a file for you to look at.

The first thing I did was to run rebuild on your arc'd curve. The bottom area was segmented and kindof broken up, and most likely causing the surface breakage.

The other thing to look at was the messy alignment. Like your base curve is slightly lower than the object to flow, so I moved them to be planar? Also, the base curve should be the same length as the flow object, if you want to be controlling the stretch and length of the flow result.

Thanks, and that would probably be really helpful, if I had any idea what you meant by "run rebuild on your arc'd curve".

I can't find a Rebuild command or any way to do anything similar other than drawing the curve over again from scratch for the 50th time.
How does one do this?

Also, I don't really Want to Stretch the cone.
When the cap is placed on the bent ice-cream cone, I want its total height to be 50mm, but I cannot come up with any way other than pure trial and error to get the heights to match so the open top is merely tilted, not displaced vertically.

Hit the tab key and type rebuild and hit enter. You can also make a shortcut with the command rebuild.

I'll make a quick video in a second.

Here you go Rick:



You'll note for the arc, I hit the tab key and type Rebuild.

I don't think that the planar placement of the curves are actually necessary. I just point out stuff like that in case your trying to really control things and placement, with regards to stretch and such.... Sloppy can produce sloppy. With flow, you can "shift" the center of the result and actually morph it if you don't watch out.

Thanks for the help. PM sent.

Hey Rick,
I responded to your pm..... We should just do it here.....

Would you like to start?

I'd love to, but I'd prefer not to have to work through it myself, as I seem to develop the twitches every time I touch anything in MOI - objects seem to spontaneously change size, move, or otherwise disintegrate when I mouse near them.
6^)

I'm skilled with TinkerCAD and a number of real graphics programs, and have brought products to market using TK, but I'm stonewalled by MOI.
Here are a couple of my earlier products:
My name visible on the bottom side of this one when you Rotate the image: http://www.leonpaulusa.com/acatalog/Tungsten_Sintered_Pommel.html
and the latest: http://www.fencing.net/forums/thread71986.html

Hi Rick, sorry you're having so much difficulty with MoI!

> I'd love to, but I'd prefer not to have to work through it myself, as I seem to develop the
> twitches every time I touch anything in MOI - objects seem to spontaneously change size,
> move, or otherwise disintegrate when I mouse near them.

This is pretty unusual - I mean MoI does have various ways you can edit things but you have to not just click but also hold down the mouse and drag a ways before they activate.

But if you drag on an object, it will move , and if you drag on an edit frame grip it will scale the object. But it's very common for many other graphics apps to do that type of stuff as well so it's a bit strange that you only have this happen with MoI only...


It seems that Burr has already answered you about the particular Flow problem, that does look like it has to do with your target curve being made up of some separate segments with some little line pieces in it - Flow really is meant to work on a smooth curve not one made up of little line bits in it.

- Michael