Hi Pilou,

That's exactly what am I trying to do but in the concept of whole thing.
I'm not sure how you achieved that.
Did you delete all the other parts and only left those particular surfaces or something else.
I'm trying to do it but with no success so far.

Thanks,

Slobodan

I managed to do it.

I had to separate everything first,
Join surfaces that will share fillet, and then apply fillet.
But now there is another problem. Look at the picture. Also, it looks like the oval surface it's not perfectly around but edgy.
When I try to blend to surfaces, it crashes MOI.
I apologize for so many questions, just trying to learn here.

Thanks,

Slobodan

Not delete something else you will obtain nothing :D
Make Copy Move first :)
Delete that you dont Want
Join some surface and curves
Make your Fillet
Repast the moved object :)

Ps If that crashed send the Report Crash to Michael !

So you must have your "Curves end" Vertical at the good place so redraw a little your form for an Harmonious form :)

Well, I'm still struggling with this.

I know what you suggested Pilou but fillet doesn't end correctly, I'm not sure why.
Do you know??

Thanks a bunch,

Slobodan

Maybe a fillet can't works on a "flat" line frontier without surface on the other side :)

Can anybody try to recreate this since it's driving me nuts and I won't be able to sleep. :( :(
Is it even posible to do it??

Thanks,

Slobodan

Hi Slobodan, I'm taking a look at it now, sorry I didn't check in earlier.

Just a couple of quick tips off the top of my head (I have't dug into your model too deep yet) - it looks like you're getting the hang of it!

After you create a surface from some curves, you probably should hide the curves, or possibly save them off to another file and delete them. The reason why is that curves have a priority in selection over surfaces (since otherwise they would be very difficult to select if you could only select them by clicking exactly on them). This means that for stuff like fillets, it is pretty easy to accidentally select one of your old input curves instead of a surface edge, which will produce a different result. This was probably a confusing issue.

Another thing is that sometimes it is good to work in surfaces, and then sometimes it is good to join surfaces together into solids and then do operations on joined edges.

If you are in a detailed area that where you are having difficulty, then that is generally where you will want to revert to separate surfaces. This is one area of flexibility that is nice in a NURBS modeler as compared to a solid modeler like SolidWorks/Inventor - in a NURBS modeler you can work on one surface at a time and join them together into a solid later on.

On the other hand, you will find that solid modelers like SolidWorks and Inventor have stronger automatic operations in several areas, especially filleting and shelling - they will be able to calculate a lot of types of fillets that MoI will fail on. But when they fail you are kind of out of luck...

Anyway that's just some generic advice and thoughts, I'll still take a look at your specific thing here.

- Michael

One other tip - you can also do a fillet by select a face of a model, and it will fillet all the edges of that face. So for instance in this case for your fillet you can select just the top face and do fillet, you don't have to select individual edges for these types.

I kind of see what your problem is, when you fillet the sort of "sub-assembly" of just those few surfaces, it doesn't know how far on the side to trim the fillet back so you get a hole there.. Still looking into it.

Ok, so one reason why blend goes crazy there is that the filleter did not do a good job of trimming the fillet piece back. If you zoom in very closely (using the Area zoom) on the bottom-left corner of that hole, you will see that the edge curve is a zig-zaggy mess which looks like this:



So that's not good! There are some cases like this where things come to a point at a shared tangent that are not handled very well, it is a difficult area of calculation.

However, the fillet surface itself is fine, it is just the trimming curves on it that are messed up. So here is how to salvage it - isolate just the fillet surface (separate the model and hide everything else). Now select the 4 edges of the fillet surface and hit delete - this will remove the trim curves from the surface and expose just the entire underlying surface.

Sometimes it is useful to get a kind of "preview peek" at the underlying surface without having to untrim by turning on control points, you can see the extent of the surface by its control point grid, and also if it looks clean or looks messy. Note that you have to have an isolated individual surface to turn on its control points.


Ok, now at this point you have this: (view from the back so the gap is clear)

The fillet has to be trimmed back now, and it has to be at the last place where it touches the upper surface. To do this, we will draw a line - here is a view from underneath - snap on to the intersection between the edge curves at the top, and then you will get a perp/perp snap for the bottom:




Now you can trim the fillet with that line. Since the line is not on the fillet, it will get sucked down on to the fillet surface by pushing the line towards the closest point of the surface, which will work fine for this case. Discard the portion to the left and you are left with this: (view back on the other side now)

This is now a cleaner hole to fill. One way to fill it is to join the surfaces together (which will also split up edges where things are touching), and then do a 2 rail sweep (use the short curves as the profiles, the longer curves as rails):

Ok, so there you go, simple huh! :) Just kidding - it seems like you happened to pick a fairly difficult model even though it seems initially like it should be easy. Things that disappear into sharp points like that tend to be a problem area for rounding/blending.

But actually this served as a good tutorial on what you can do when things go wrong though! So that part was good. :)

I think that a lot of your problems would have been avoided if the filleter would have trimmed the fillet piece off straight down from that intersection (like the line I drew above) instead of trying to sort of slice it at an angle. Maybe in the future I will be able to figure out some way to set it to do this so that it will give you a cleaner piece to deal with right off the bat there, that would have helped a lot in this case.

Please let me know if you need any additional clarification about any one of these steps.

- Michael

Nurbs are always "fill holes" :)
Better if these holes have sides :D

I get away from the computer for couple of hours and things are realy happening at MOI!! :)


Hi Michael,

How do I thank you for taking time to do this??
I'm glad that I didn't totaly waist your time on this. I guess we found something to improve on in MOI.
Thank you so much for your explaination and I'll let you know how it goes when I get time to play with it. May be tomorrow.
I don't think I should have a problem following your steps.

It seemed like a bathroom sink should be easy enough model to start with.. hehehehehe May be not.. :)

Thank you again and this is one great community.

Slobodan

> How do I thank you for taking time to do this??

It's no problem Slobodan, answering questions like this really help this forum to be useful as a learning tool to more people. And it's kind of like the equivalent of good exercise for me! Keeps me in shape! :)


> I don't think I should have a problem following your steps.

Ok - don't be hesitant to ask if anything needs clarification.


> It seemed like a bathroom sink should be easy enough model to start with.. hehehehehe May be not.. :)

:) I'm sure you're already familiar with this, but sometimes one innocent little detail ends up making things surprisingly complex when it comes to filleting in particular.


Anyway, thanks for posting a nice example model for what you were trying to do. It is a lot easier to help out with a specific example like this than just talking too much in general.

- Michael