Hi Michael,

thanks for your help. Yes, it makes sense, and actually now that you mention it, I remember that I've read about the small fillets in another thread. As far as adding adjacent edges for the fillets, that was actually anyway my intention, to be precise I tried to fillet all edges but the ones on the bottom face, didn't work though, that's why I tried to fillet a few at a time ... the rest is history.

It still doesn't work on the whole part, so I started filleting all the individual parts before I union them (4 parts), I can get it to work on three of them, the fourth I'm still experimenting, trying to figure it out before I bother you again.

I have to say, I'm amazed how fast, and how extensive and thourough the help on this forum is, especially from you Michael. I really appreciate it.

Armin

Hi Armin,

re: fillet all edges - there are a couple of areas in here that have things split up into a couple of pieces instead of one big piece which MoI's filleter does not like. Also a couple of edges were split into multiple edge pieces.

For example here:



I've attached a tuned-up version, fillet_problem_fixed_3dm.zip - if you unzip that and load in that version, you should now be able to fillet the whole model in one go, here is what it looks like with radius 0.1 :




Basically if you can get things into a sort of "one single surface sheet per smooth area", that has a lot better shot at being filleted. The filleter doesn't even like it if you have planes made up of several co-planar fragments, instead of one big trimmed plane.

- Michael

Hi Michael, thanks for sending me that file, and yes it works, that's kinda what I was heading for. Though I don't really want to have a fillet around the bottom face or the edges of that "tunnel", which actually raises another question. Since I would have to select a huge amount of edges to achieve my goal, is there an easier way? I'm thinking of something like selecting the whole part and than deselecting just the edges I don't want to be filleted? Or maybe selecting the edges I don't want to be rounded and than invert my selection?

I was also playing a little bit more around with those parts myself, after posting my initial problem yesterday. I also noticed that split on the curved face and was wondering if this might be the problem. So I started remodeling that part. My first assumption was that the problem might have been caused by some edges that I copied from an existing part, but after the extrusion the splits didn't show up. So I took the next step and cut that rounded face (Boolean Diff) with a curve, also a copied edge from existing geometrie. Since this edge initially wasn't long enough to cut through the whole part, I extended it at both ends. And the width of the extension is exactly where that trimmed surface gets split. Not sure if this is supposed to happen? Anyways after trimming the part with a new curve (arc), the curved surface looked ok, no more split lines, and of course the fillet command works now. I attached that file, maybe you can see why this extended curve behaves that way, and maybe this is just the way it is? Does this also mean DO NOT USE EXTENDED CURVES FOR TRIMMING? I also noticed, after turning on the points for that particular curve, there are a lot (relative :) ) of points, why don't they cause the trimmed surface to split?

One more question. In case I run into another split face in the future, is there a way to repair that without recreating the part? I guess I could delete that face and just fill it in with the planar command?

Thanks in advance
Armin

Hi Armin,

> Since I would have to select a huge amount of edges to
> achieve my goal, is there an easier way?

Just use a window select - after you select one edge with a click, then you can use window select to target additional edges.

Also there are different window select modes, if you start from the left and go towards the right it will only use things that are completely captured inside the window, and if you start on the right and go towards the left it will grab any that intersect the window.

So for a case like this, you want to use Right-to-left mode (it will show a dashed window outline) and just barely miss the bottom part to get what you want.

Here's a video:



It doesn't matter which edge you select first (as long as it is not one of the ones on the bottom that you don't want selected) - when any edge or face is selected then window select targets edges or faces as well.


> I'm thinking of something like selecting the whole part
> and than deselecting just the edges I don't want to be filleted?

You could do that too, but the way above is faster I think. If you did want to deselect edges you would probably want to do a window deselect of them instead of a one-by-one click - to do that hold down Ctrl when doing the window.


> Or maybe selecting the edges I don't want to be rounded
> and than invert my selection?

Yeah, you can do that as well, Invert is available under the Select menu on the side pane.

It can be convenient to set up invert on a keyboard shortcut, so you can type I for invert. To do that go to Options / Shortcut keys and put in this for the command:

script:var gd = moi.geometryDatabase; gd.invertSelection();

I'll try to look at your other questions a bit later.

- Michael

Hi Armin, to answer another part of your questions:

> And the width of the extension is exactly where that trimmed
> surface gets split. Not sure if this is supposed to happen?

Yeah if I understand you correctly that part is supposed to happen. Doing a cutting operation with a planar curve is the equivalent of extruding that curve out into a surface. When you do an extrude of a curve made up of multiple segments, you will get one surface per segment for the extrusion result.


> Anyways after trimming the part with a new curve (arc), the
> curved surface looked ok, no more split lines, and of course the
> fillet command works now. I attached that file, maybe you can see
> why this extended curve behaves that way, and maybe this is just
> the way it is?

Yeah, that is just the way that curve extension currently works - if you extend a line, then you will get a longer single line, and if you extend an arc you will get a longer single arc.

But if you extend just a "general" curve like this one you have here (looks like it was probably the result of some surface intersections or something like that), then the extension is a line segment that is added as an additional segment to the curve, so you get a multi-segment curve in that case which you can see if you use Edit/Separate on it to break it into different pieces.

I do want to add some options to extend in the future though, it should be possible to add an option that will make a "smooth" extension that could make lengthen that piece without making it segmented. I'm not quite sure when that will happen yet.


> I also noticed, after turning on the points for that particular curve,
> there are a lot (relative :) ) of points, why don't they cause the trimmed
> surface to split?

It is possible for a curve to have a lot of points internal to it but still be a single segment as long as the curve has a high degree of smoothness at each of those internal points.


> Does this also mean DO NOT USE EXTENDED CURVES FOR TRIMMING?

Well, not necessarily... It kind of depends on the situation.

But for filleting, things that are broken into more segments can cause problems. The way it causes problems is that the filleter will try to produce a fillet surface for every edge that you have, and then when it has produced all these fillet fragments, it has to try and trim them to one another, trimming surfaces that are tangent when they touch each other tends to be a difficult area of calculation, unfortunately. So currently if you just generally reduce the number of fragments and separate pieces in your model it will tend to avoid some of the areas where the filleter has difficulty in.

- Michael

Hi Armin,

> One more question. In case I run into another split face in
> the future, is there a way to repair that without recreating
> the part?

Often times you can do a bit of localized surgery to the shape rather than full rebuild.

For example, you can select faces, delete them, sweep in a replacement face, trim if necessary to the other existing edges, then use Join to glue it in and make a solid again.

There is a tutorial here: http://moi3d.com/forum/index.php?webtag=MOI&msg=446.17
which goes into some details on how to do some "low level" surface tweaking type stuff, like in that case it is a boolean that was done in the wrong place, and the tutorial is about how to salvage the shape by repairing localized areas of it.


> I guess I could delete that face and just fill it in with the planar command?

Yeah the things you want to repair are all planar then that is the easiest way.

- Michael

Hi Michael, thanks again. Didn't know you can box select the way you explained it.

Armin

Hi Armin, no problem!

I think that kind of edge selection is covered in one part of the Pod video tutorial if I remember right. Those videos are available from here: http://moi3d.com/1.0/docs/tutorials.htm

Those are definitely worth watching since they go kind of step-by-step through the whole workflow to build a few things.

- Michael