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Rounds

mgnt8

New member
Well, a new website but an old subject-


This has been bugging me for a long time but I've never been able to get a good answer to it. When a round fails and you get the message suggestion:


"Try to create feature as "Unattached", and complete it using quilts."


does this ever work? I admit out of desparation, I actually tried it once or twice but it never worked. What do you do with the quilt - use it for a cut? Never works.


Anybody know what this is about?
 
I'm sure I'm not talking about the same kind of rounds here, but here it goes. When I get a round that fails I usually can go back and re-select the edges that the round uses. This is of course in the failure mode.
 
The highlited edges that fail show up as thick red lines, I just LMB select each red line and then re-select each line (holding the control key). Most of the time this is ok, but some failures require me to not only de-select and re-select but also change radius value.
 
on rounds if u skip a beat on the cntrl holding it starts
another group. go into the properties menu and make sure ur adding the
references to the correct group
 
That's a very good point, puppet. I know that I don't use that part of the round feature (multiple sets) as much as I could because you can't do that in other CAD packages.
smiley2.gif
 
OK, my original question was not how to select edges for rounds but how to create round as "Unattatched" and complete it using quilts.
 
unattached simply leaves the rounds as surfaces instead of creating a solid feature with them. You can then treat them just like any other surface (quilt). You get the same functionality as if you created a surface round instead of a solid round.


PTC's advanced rounds class uses this functionality to create complex transitions between rounds that can not be accomplished with the Advanced Rounds transitions.


So ,yes... creating rounds as surfaces (either directly by surface rounds or indirectly by unattached solid rounds) has some advantages that make them useful in complex geometry creation.


If your solid round fails and you leave it as a quilt, simply trying to make a cut or a protrusion with it afterwords should not work... This is exactly what Pro/E would have done if there wasn't a problem in the first place. You will probably need to investigate what would cause the creation of a cut/protrusion with that surface to fail. It could be some tiny edges or overlapping surface or any number of things. f you are able to tweak your resulting surface such that these problems are eliminated, then you'll be able to finish your round... The bottom line is, you're going to need to use a little surfacing troubleshooting to get the job done.


-Brian
Edited by: Brian_Adkins
 
Thanks for the explanation. It seems pointless for Pro/E to suggest completing the round as a surface after it fails when there's no way it can be used for a cut or protrusion. Like you said, Pro/E would have done that anyway if there wasn't a problem in the first place. I suppose the resulting surface might possiblyyield some information about why the round failed, but this is more of an analysis technique.


In the end, "...create feature as "Unattached", and complete it using quilts" doesn'tseem like a solution at all. Why suggest it as one?
 
There are lots of users with surfacing skills who can quickly whip a 'broken' round into shape by tweaking the surface and then create a solid feature from it. Usually by trimming and/or extending the surface so that it meshes better with the surrounding solid geometry.


-Brian
 
The problem I have had is merging the surface afterwards. Creating rounds as surfaces has often worked (with a little tweaking) where a solid feature failed. Especially where blends or changing radiuses are required. After I had the feature then I had difficulty merging or quilting and changing back to a fully solids part.
 
That's my point. Trimming or extendingthe resulting quilt doesn't help me because I'm rounding an edge on a complex surface. Its not going to merge or solidify no matter how much I "tweak" it.
 
Where there is a will, there is a way. Many times the rounds will cut across edges of surfaces and not be able to complete the round. Sometimes manipulating the radius value... Lets say I need a R0.5 and it does not work. R0.49 or R0.51 might work which is usually good enough for government work. Sometimes changing the type of round to variable using the R0.5 might work. Sometimes changing the round to Surf/Surf will work when other avenues may not. Sometimes you need to put one round in before another. Other times you need to simplify the round by selecting single edges instead of multiple edges.


The last resort would be to convert the round to a surface. Why make things more difficult than they should or need to be. And, sometimes you have to accept a geom check and keep moving on
smiley19.gif
 

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