Hi Paul, welcome to MoI and to the forum!

> Right now I'm working on a piano
> model. I have several key Objects defined, but now I'd like
> to group them so I can hide them while I work on other
> parts of the piano.

The easiest way to do that currently is to assign a name to those objects, which you do by selecting them and then clicking on the name line in the properties panel in the upper-right corner of the main window here (where it says "unnamed" which shows the current object name):




Once you have assigned your objects a name (you can have more than one object assigned to the same name to make a type of group), there will then be an entry in the scene browser "Objects" section with that name in it and you can use the eye icon there to hide and show that object set.

You can also use "Styles" in the scene browser to organize objects into different color sets as well, some more information on the scene browser here:
http://moi3d.com/2.0/docs/moi_command_reference11.htm#scenebrowser


> Secondly, I absolutely love the Fillet tool in MoI but I run into
> difficulties with it frequently. The problem I have is, sometimes
> I end up with edges that shoot off into space when a bevel
> crosses a perpendicular edge.

Can you please post an example file for the problem?

Fillet pieces that shoot off like that are usually caused by some difficulty in the fillet calculation step where it tries to intersect 2 fillet pieces with one another. One situation where that can tend to happen is if your model is constructed with pieces that come within a few degrees of being tangent to one another but are still not quite tangent. Intersection calculations between things that are set up like that become more difficult.

But it's hard to know for sure what you ran into without seeing an example file - filleting involves a lot of various difficult calculations so there are quite a variety of different things that can make it have problems, it's hard to know for sure which particular thing you ran into without seeing your specific example.


> Are there any tutorials or documentation on getting good Fillet's?

Some recent discussion and links here:
http://moi3d.com/forum/index.php?webtag=MOI&msg=4751.1


> Finally, I have been exporting OBJs from MoI into 3D Coat for
> painting, but 3D Coat is complaining that the UVs are incorrect
> (too large is the error I think I've seen). Is there a way to edit
> the UVs prior to export to fix this?

Hmmm, I have not actually heard of this error before - but basically the UVs that MoI creates on export are really basic - every surface has UVs but they all map to the same full 0,0 to 1,1, unit texture square, so basically every surface shares the same texture area. If you want to paint on an object and have different paint show up on different surfaces, you will need to make a different uv mapping on it where each mesh has its own separate small region of the texture square rather than them all sharing the same region.

MoI does not itself have any tools for editing the UVs - usually polygon modeling programs have the tools to do that part. I think 3D-Coat has some tools for doing that, it's discussed some here:
http://3d-coat.com/uv-mapping/

You'll basically want to throw out MoI's default UV coordinates and have 3D-coat create a new UV structure that is more suited for painting, you'll probably do that by using the "unwrap" function in 3D-coat to generate the UVs.

There are also some specialized programs that just do UV editing, like:

UVMapper: http://www.uvmapper.com/
Unwrap3D: http://www.unwrap3d.com/u3d/index.aspx
Unfold3D: http://www.polygonal-design.fr/


At some point in the future I'd like to make MoI create UVs that would be suitable for painting, but currently you've got to use some other program to set up the UVs for that.

- Michael