hi guys,
i am sure there is to much talk about Fillet and Michael Gibson did great work and explain the right way to Fillet but however my small mind can't really understand it ;( i just start using Moi and i really love it so much some time i lost and this because of me not the app however i made this small model for learning and i have small problem with:
1- Fillet this edge please see the attach image.
2- run merge command but same not working with me here.
3- the last question is joint different than merge and boolean union.

thank you in advance and i attach the file

Hi albehany - the boolean commands like Merge and Union are primarily for combining 2 or more solid objects with each other, with the objects being intersected and some material removed. The merge command cuts the objects with each other and leaves all the pieces, while boolean union keeps the outside pieces and removes the pieces that were contained within both volumes.

Neither Merge nor Union would work on your object here, for a couple of reasons - the first is that you don't have multiple solids, you've got just one object. The second is that your object is not a closed solid, it has several open edges.

It tends to be better to build something like this by starting with a solid and then doing booleans on it, it kind of looks like you may be building things out of individual surfaces rather than working with solids?

Are you coming from a polygon modeling background? You might check out here for some tips for polygon modelers:
http://moi3d.com/forum/index.php?webtag=MOI&msg=4865.2


Fillet is having problems due to a degenerate slivery-thin face that's right along the area you want to fillet, in these areas here:




If you look closely at the indicated areas above, you can see the edges in those spots are slightly darker - that means that there isn't just one edge there which is what you'd need in order to do a fillet. When it's a bit darker like that, that means there are multiple edges being drawn on top of each other there. Then I deleted some of the surrounding faces and then could more easily see these slivery thin surface fragments:




Filleting will definitely get confused by that type of structure with some extremely slivery thin faces.

The other thing that would help is if the model had larger surfaces like the front face being all one surface rather than it being multiple pieces like you currently have.

- Michael

Hi albehany, so I took a closer look at the cutout area and it definitely looks like you're constructing things in a "patch by patch" manner which is not optimal for NURBS modeling.

The way I'd recommend doing it is to try and work with solids instead. With that method instead of trying to build the cutout by drawing all the curves for it and then trying to build lofts or networks between pieces, you would instead start with a solid and have a second solid as a cutting tool and use boolean difference to cut the main object. Those steps look more like this (also see attached 3DM file):



So the main idea is the cutout comes from a boolean operation between 2 solids, rather than trying to build the cutout by individual surfacing operations. You want to work with 2D curves and solids as much as possible, you want to try and avoid drawing in all the 3D edges initially and then trying to build surfaces between all those edges. For NURBS modeling it's best if many of the final edges come from where 2 solids intersected each other from a boolean operation.

Now with this object you should be able to fillet the edges you wanted, up to a maximum of about 0.5 units - any more than that and it will run into the neighboring edge:






Hope this helps!

- Michael

Michael thank you so much i understand now. and yes i coming from poly modelling :)
one last thing one of strong reason i love moi is the Deep answer i get from this forum i never have this experience with other app.