Newbie Problem Shell/Offset complex Geo All  1-6  7-14

 From: Michael Gibson 17 May 2010  (7 of 14)
 3543.7 In reply to 3543.4 Hi Rogurt, see here for an example of how to make a rounded edge without making a degenerate corner: http://moi3d.com/forum/index.php?webtag=MOI&msg=3473.3 - Michael

 From: Michael Gibson 17 May 2010  (8 of 14)
 3543.8 In reply to 3543.6 Hi Rogurt, also see this other post here: http://moi3d.com/forum/index.php?webtag=MOI&msg=1127.4 For a description and illustration of what a degenerate corner on a surface looks like. When a surface has its own control point grid organized in this way it is easy for the surface to become self intersecting as shown there, and that basically creates a micro tiny fold in the surface and that means the surface normal (which is a key thing used in offsets) can flip around wildly in that little spot. So rather than making a surface that has that kind of degenerate corner in it, it will be better for offset to have a larger surface that has its control points in a more regular grid pattern instead of having corners of the grid bunched or stretched, and then have a trim curve that cuts away the excess area of the surface. You can have all kinds of complex trim curves on a surface without it affecting the surface normal, but if the surface's own control points are bunched up or folded back on themselves it is a no-go for offsetting that. - Michael EDITED: 17 May 2010 by MICHAEL GIBSON

 From: Rogurt 18 May 2010  (9 of 14)
 3543.9 In reply to 3543.8 Thank you all. @Paolo I understand these 3 samples are edits displaying the development from left to right. I tried to offset/shell the left one by 0,2 - wont work. @Michael I am using the V1 30 days trial. I havenĀ“t got a key so no v2 beta download. EDITED: 18 May 2010 by ROGURT

 From: Rogurt 18 May 2010  (10 of 14)
 3543.10 In reply to 3543.9 All right. Now I dumped the whole shell attempt and duplicated the object, scaled it and did a boole. Result looks fine and calculation is way faster than "shell". So on to the next question: how can I bevel the upper edges via "filet" since I havent got continuus edges/splines I could select... Thanx for your patience with me so far :-)

 From: Michael Gibson 18 May 2010  (11 of 14)
 3543.11 In reply to 3543.10 > So on to the next question: how can I bevel the upper > edges via "filet" since I havent got continuus edges/splines > I could select... Hi Rogurt, I'm not exactly sure wehat you mean by not having "continuous edges" - surely you must have a set of edges that touch each other? You can select multiple edges to be filleted, you don't only have to select a single edge at a time. So for example here I've selected 3 different edges at the top of this object: And then I ran Fillet to make this result: Edges that are not smooth to one another will have "corner patches" added to them to connect them up. One thing to be aware of though is that Fillet is also a sensitive command similar in several ways to Offset. In fact a part of the fillet calculation involves generating offset surfaces and intersecting them. So if you have things like little folded areas or tight bends in your shapes, it is likely to cause a problem with fillet in a similar way it caused problems with offsets. - Michael Attachments: