I thought I'd put the "flow on revolved surface" to the test - by making a mesh speaker grill.
If you have a speaker grill, you'd surely have a speaker, so lets make that:

The guts:
1) Draw a profile shape of half the side of the speaker assembly. Use lines, arcs, fillets and whatever else.
There are usually three main parts to the working guts of an audio speaker - Magnet and core, solenoid are (often obscured), and the cone.
2) Revolve the profile to make the shape.
You are now 1/3 done!


Coloring:
- It helps to color the regions so that it is easier to prep for rendering later on.


Next, it the cone harness:
1) Draw a circle
2) Copy and position the circles to represent the main body of the harness - you'll see lower...


Support ribs:
- These will be a series of squared ridges that run up the harness body, they will have a consistent size along the length,
so they'll be lofted from two profiles carrying consistently sized ridges.
1) Draw a Rectangle with rounded corners.
2) Rotate to position - this is not necessary at this point, but it was what I did.


Make cuts:
- We only need the top part of the rectangle and we also need a fillet.
1) Make a circle snapped to an intersecting point between one of your circles and the rectangle.
2) Copy the circle to the other intersection.


Rotate:
1) Either Rotational Array, or use Rotate snapping to the center and inputting a snap angle increment of appropriate degrees.
- I made two sets and made three copies around the perimeter.


Two sets:
- do this for two rings, one near the bottom and one near the top.


Trim:
1) Select the rectangles, small circles and large circles - Mutual Trim or Add Points.
2) Delete unneeded stuff.


Fillets:
- Blend the ends to make fillets.
You may also consider adding fillets to sharp corners.


Prep for blends:
- I want to blend the edges of this lofted harness body section,
The edges have to be one piece or there'll be difficulty later.
1) Rebuild profile rings so that they are one consistent spline with no cuts.


Loft to make harness body:
1) Loft new profiles.


Loft to make bottom section:
1) Loft bottom rings together to leave a healthy gap between that and the bottom of the harness body.


Blend edges:
1) Select the edges of the two lofts - blend.
2) Join surfaces.


Create top ridges:
1) Loft top rings with the Straight setting.


Blend edges:
1) select the edges of both the top of the harness and the bottom of the top ridge. - Blend to make a smooth transition.


Smooth the ridge:
1) Fillet the corner edges of the top ridge.
2) Make sure the different sections are Joined.


Make holes:
1) Draw a neat shape in a view port that represents a clear symmetrical side to the harness body.
2) Mirror and Join


Make copies:
1) Rotation Array to produce copies around harness body.


Projections:
1) Prject each shape into the body sides through the center.
2) Delete back projection.
3) Trim projected shape into the harness shape.
4) Delete holes.


Punch-in:
1) Extrude the hole shape inward towards the center.
2) Join surfaces.


Round edges:
1) Fillet the edges.


Shell:
1) Shell or Offset surface to add thickness to the harness object.


Nice edges:
- If your edges between the original harness body and it's offset surface are not solid,
give them a nice edge with an edge Blend.
1) Select edges, Blend
2) Join
- If you used a box method that worked to make a solid shape, then use Fillet.

Harness brace flange:
- We need an interesting looking flange section at the top with three adjustable screw holes.
We need a "cam" shape, which is a three-sided triangular shape with extremely rounded corner.
A cam always has a consistent distance from one side to the other through the center.
I don't know if that is true for my shape here.
1) Make circle
2) Rebuild using # of Points = 3. You get a spline made from only three points!


Thicken:
1) Extrude a combination of the outer cam shape and an inner circle representing the cone diameter.
2) Delete the bottom surface, so that it is and open shape.


Interesting edges:
1) Draw a free-form curve to make the shape. Mirror and join.


Cut:
1) Project the shape to the edges of the cam's extrusion.
2) Trim the front projection and delete the bottom portions.


Add thickness:
- Run through the steps to create thickness on the harness body.


Make more nice edges:
1) Blend edges
2) Join


Smooth corners:
1) Select sharp corners of object and Fillet.


Terminator!
We need a terminal strip for the electrical connections.
1) Draw circles and rectangles
2) Boolean Union to create the shapes.


Construct:
1) Extrude the shapes.
2) Create rivets by making profile and Revolving.
3) Position the whole component on one of the tabs of the harness body.
- Because this is at a strange angle, use the Orient tool.


Wires:
1) Draw Free-form curves and edit their points to position.
2) Mirror one to make the other.
3) Draw circle and Sweep that shape along the curves.


Solder:
Make a solder blob by Revolving a profile.


Details:
I made these reinforcement tabs to bring the wires to the inside surface of the cone, where wires go to the core solenoid.
I used shape projected to the cone surface, extrude and fillet.


Come Down To the Mesh Grill:
1) Using Free-form curve in ONE single run, make the profile of the speaker cover grill basket.


If you do not have access to MoI V3 Beta - Here is an alternate method:
1) Revolve profile to make the cover's shape.
2) Array copies of lines (wavy) and Project them to the shape's surface.
3) Rotate this result to make a mesh
4) Sweep a circle along these projected lines

Matching:
1) Use Free-form curve to make a straight line curve.
- Match the points placement so that the physical point to point distances of the profile line are represented.
Think of the profile curve as being "unwrapped"
2) Revolve both profiles.
- NOTE: Move one of the straight curve points up or down a little. If you do not,
MoI will make a planar circle. We need a "Reference" circle with it's associated web knots.
3) Go to a side view and pull the editing handles of the top Reference surface until it is "Flat"


These are the Reference and Target surface for the V3 Beta Flow command...


Wiggly:
To make a weaving mesh, each strand needs to wave - or be made from a sine wave to be exact.
Either use the sine wave script or make a representative section with the Free-form curve.
Copy these waves to make the extent of the mesh section and join.
Note: For Flow to operate expediently, it is important that each object section consist of one surface only!
Use Rebuild to reconstruct the sine wave curve section.


Since the sections weave under and over, make the next one over a flipped copy.


Array the sections to cover the span.
Make a rotated copy and flip to create the opposing weaves.
If your math and measurements are correct, you should have a seamless weave with no collisions.
...This was not my result. ;-)


Here is the completed mesh in it's flat form. It is aligned with the Reference circle.


FLOW!!!
- Try the Flow command with only one section at first to gauge for time - try more at once if possible.
1) Flow will prompt you to select the object to flow.
2) You'll be prompted to select the Reference surface.
3) You'll be prompted to select the Target surface.
........wait........
It helps to have "delete original objects" to help organize the process.


Trim:
Use the "cam" shape to trim the edges of the new formed mesh. Trim additional holes.
- I can say outright, that these objects did not want to all trim without error, do the best you can.



I also made a gasket to sandwich between the wire mesh and the flange.
That should be flatter copy of the cam/circle extrusion with the holes, all filleted.



And Finally - it all comes together!



I will be trying some renders out soon,
until then if you like - feel free to download this model to check it out:
http://www.mediafire.com/?3tlre2zc6y1qh

Use it for your own projects where you require speakers for a boom box or audio system, add you own grill cover.



.

Great work Majik,downloaded and thanks...


for Rich:
this is a similar case like the pineapple when a complex geometry(mesh speaker or pineapple patterns)can be made by render engine (opacity map for mesh speaker and displacement map for pineapple)
you are right,but here we are to model not to render,sometime could be necessary have a geometry

Another one detailed tutorial!

Thanks guys!

You got it right, m-dynamics...

Were here to push the limits of MoI and learn how to solve any modeling challenge that arises.
Yes, V-Ray with some displacement maps could do the job on the render, but the point of my example here is to show the versatility of the new Flow tool,
and thus MoI's underestimated power of it's surface modeling abilities.

Excellent work Majik, thanks for sharing!

Really nice, detailed model Majik!

I wanted to try a quick render in KeyShot, but ran out of memory saving as OBJ, even with poly count set at minimum. Then tried importing the 3DM into KeyShot, and the import failed :(

If I get some time I may try exporting parts of the model as OBJ and re-assemble in KeyShot, but I suspect the grill complexity will be a bit much to export.

Ed

My plans were to try going the SketchUp route.
I'll export the different sections separately - this is because the SketchUp .skp export filter in MoI does not save the material data, so everything comes in as white.
IF MoI will export the mesh object (with a lower poly structure, of course). Then I have no doubt that SketchUp will not have too much difficulty handling for export into Kerkythea.

This is a test, indeed.


...You could try exporting just chunks or x-number of strands of the mesh object...

Why pass by Sketchup?
Kerkythea open in direct OBJ, 3DS....
Seems these formats are inside Moi export ;)
Kerkythea is also a standalone ;)
As you export part by part just add material when they arrive in kerky ;)

Thanks for the tutorial. Speaker looks really great.. Thumbs up. :-)



>>>>
for Rich:
this is a similar case like the pineapple when a complex geometry(mesh speaker or pineapple patterns)can be made by render engine (opacity map for mesh speaker and displacement map for pineapple)
you are right,but here we are to model not to render,sometime could be necessary have a geometry
<<<<<

Please let this rest. It was not an attack against you, I just was trying to be helpful.
You already told me your thoughts about this. No need to tell me this again.

Peace,
Rich_Art. ;-)

Hold on.... let me check that...

Holy cats!!!!! It not only takes .obj files - but it's in 64 bit ... and I have 4x2 cores!
...no materials yet, no lights... It may take a while to set up.

Now I can go directly from MoI to render.
Thanks Pilou!

Cool tutorial, thanks!

Marc

This render was just one light and a simple chrome material. ...I need time to set everything up right.

Does anyone know why this model imported on it's side? (.obj)
AND... does the .obj exporter know to "smooth" the edges of it's surface polys?

I should build a universal modeling room with good lights and a nice camera setup, so all I have to do is import the .obj model.

I had MoI crash at first when exporting to the .skp, but I chose an extremely low poly setting. It worked after sitting for a bit.

Hi Mike,

> Does anyone know why this model imported on it's side? (.obj)

What program are you importing it into?

Some programs interpret the Y axis to be the up direction and other programs interpret the Z axis to be the up direction.

You can adjust how MoI does the export with a setting under Options > Import/Export > OBJ options > Orientation.


> AND... does the .obj exporter know to "smooth" the edges of it's surface polys?

I'm not sure exactly what you mean by this - but the OBJ file is exported with vertex normals information which controls how the smooth shading is done in the rendering program.


> I had MoI crash at first when exporting to the .skp, but I chose
> an extremely low poly setting. It worked after sitting for a bit.

If you had a crash dump file generated (a moi_report.zip file) can you please send it in to me at moi@moi3d.com so I can take a look at it? I have seen a couple of different crashes in the SkpWriter library before though involving points merging together. Those are difficult for me to fix up since it's a compiled library provided by SketchUp and the source code is not available for it.

Also SketchUp does not allow any polygons to exist that have edges less than 0.001 inches in size (I think that's it), it just ignores little polygons like that or may possibly try to merge their points together with neighboring ones making degenerate stuff. So SKP format is not a good format to do a very high density output to since it does not fundamentally handle little tiny polygons.

- Michael

Thanks Michael,

I'm using Kerkythea-v2.5.2 Beta 64bit.

I just imported a .obj file made from MoI and I got this:


There are all kinds of bad things happening. This is without the massive mesh object. Am I doing something wrong?

Where is this report file located, or was it something it wanted to save but did not get a chance?

What I mean by "smoothing" (SU term) is an attribute between two polys where they tell the renderer to either Phong blend them or to allow them to look "faceted".




Tried a .3ds file. I didn't come in bad like that. It was tiny however and the colors were gone. The materials list on the side listed every object in the model instead.

The setting to "Z-Up" fixed that, but I'm having degenerated polys everywhere as show in the pic. I tried lower angle-out settings too.

Try first with very small objects ;)
Not sure that the format 3Ds keep the color! skp no (and not also any names) you must export in 3Ds then explode in Sketchup
objects named must keeping but with maybe name become something like ob01, ob02 etc...

Hi Mike,

> I just imported a .obj file made from MoI and I got this:

That's the kind of thing that happens when a renderer tries to triangulate a complex n-gon but doesn't quite do a good enough job of it and has triangles kind of leaking to the outside of the n-gon instead of only generating triangles inside of the n-gon.

You might want to send that file to the Kerkythea as a bug report for an example of an n-gon triangulation failure.

In the meantime, to avoid that problem use the "Output: Quads & Triangles" option when exporting out from MoI rather than "Output: N-gons". That will use MoI's mechanism for triangulating the n-gon instead of relying on Kerkythea to do it.

Generating a good triangulation from complex n-gons is a fairly tricky business - some programs are not very refined in that particular area so if you encounter that you shouldn't export n-gons to them.


> Where is this report file located, or was it something it wanted
> to save but did not get a chance?

It depends whether you're running in XP or if you're running on Vista or Win7 with UAC enabled. Under XP they'll be written to the same location as moi.exe .

With UAC enabled in Vista or Win7, programs are prevented from writing to the "Program Files" folder, and in that case it will go to your %Temp% folder - go to Start > Run and put in %Temp% to go to that folder.


> What I mean by "smoothing" (SU term) is an attribute between
> two polys where they tell the renderer to either Phong blend them
> or to allow them to look "faceted".

When exporting to OBJ format MoI does export vertex normals that should be used by the renderer to handle phong shading.

SketchUp however is an exception and doesn't make use of that particular vertex normal data like other renderers - instead SketchUp always calculates its own vertex normals from the polygon data and instead relies on flags on each edge for whether it's supposed to be a smooth looking boundary or not. When you export from MoI to SKP format MoI's exporter will set those edge flags so edges on polygons from a smooth surface are both hidden and have their smooth flag set.

For going to Kerkythea I believe that it will make use of the vertex normals in the OBJ file to do the shading, so the data that MoI exports there will directly control the phong shading in that case. That tends to give the best results because the vertex normals come from the original NURBS surface, so using them to do the shading makes the polygons shade in the exact same way as the original surface.

In SketchUp the shading tends to be a little bit off since it doesn't use the original vertex normals and instead cooks up its own from the polygon data.

- Michael

Hi Mike, looks like you added some more to your post that I didn't see.

> Tried a .3ds file. I didn't come in bad like that. It was tiny
> however and the colors were gone. The materials list on the
> side listed every object in the model instead.

MoI currently only exports style/material information to LWO and OBJ polygon formats.

3DS should generally be avoided - it's a really antique old format and has a lot of limits in it like a 16-bit numeric limit for the max number of vertices in a single mesh, and no provision for vertex normals or polygons with more than 3 sides.

Only use 3DS as a last resort method, you will usually get much better results with OBJ files.


> The setting to "Z-Up" fixed that, but I'm having degenerated
> polys everywhere as show in the pic. I tried lower angle-out
> settings too.

That's because you're exporting n-gons and the n-gon triangulation on Kerkythea is a bit buggy with handling complex n-gons, which is fairly common since it's a bit of a tricky thing to make really robust.

If you switch to export Quads & Triangles or Triangles only out of MoI it will avoid that problem and it should work a lot better for you.

- Michael

Whew!

Bless you Michael!!!

Exporting with Quads and Triangle did the trick - And the materials with the naming was retained!
This is wonderful!


And hopefully, the positioning data is retained, so that Kerky puts everything where I left them in MoI, instead of centering newly merged into the scene - but I'll have to experiment with that.

Hi Mike, I'm glad that's working for you now!

> And hopefully, the positioning data is retained, so that
> Kerky puts everything where I left them in MoI, instead
> of centering newly merged into the scene - but I'll have
> to experiment with that.

MoI does not alter the object's location when it creates the OBJ file so if you're seeing something like imported objects being centered that is something that Kerkythea is deciding to do to the import - there is probably some setting in it that you can change to make it stop doing that.

- Michael