AnsweredAssumed Answered

pipe, not sweep

Question asked by irmeli rehbein on May 20, 2012
Latest reply on May 26, 2012 by irmeli rehbein

we all know, sometimes if you want to add a very shallow or steep chamfer (one direction is much bigger than the other) the feature does not work.

 

pipe_1.JPG

 

pipe_2.JPG

 

 

now in other programs you have a pipe command where you select any 2d or 3d sketch and input the radius of the pipe.

in solidworks i have to use the sweep command - so i have to create another sketch (circle) and extrude it along the 3d sketch.

pipe_3.JPG

 

 

 

with this swept surface i can trim away. bottom surfaces trimmed by big sweep.

 

pipe_4.JPG

 

 

i can use different radii for the trims. small radius for the top trim.

pipe_5.JPG

 

and from there i can loft these edges with compound curves.

pipe_6.JPG

 

 

the problem is - the swept surface is not a very clean surface. now of course i can't have a equal or bigger radius for the profile, than the minimal radius of the path curve.

 

but even when i chose a smaller one, the swept surface is wrinkly (due to surface tensions) and results in a nasty trim. i checked all options of the swept surface like minimum twist etc..it often results in a bad surface when the radius is a bit big.

 

--> so i wish we had a pipe command that gives me a clean surface or solid from a single 2d or 3d sketch.

 

 

so here is a cumbersome way (on another part)

 

again, i want a very shallow chamfer, going 1mm down and 3mm outside

chamfer_1.JPG

 

chamfer_2.JPG

 

 

so from the top edge i use a ruled surface going inside the hole tangent to the surface. then another ruled surface going down, perpendicular to the first ruled surface. then again perpendicular to the second another ruled surface - big enough to penetrate the extruded hole. this way i now have a clean ruled surface with wich i can trim.

chamfer_3.JPG

 

 

trimmed away surface with ruled surface

chamfer_4.JPG

 

 

for the top surface, an offset curve from the original curve that create the hole is fine. i trim with that offset curve.

chamfer_5.JPG

 

now i can loft or patch the surface and filet it.

chamfer_6.JPG

 

 

i know there are many other ways to do this, i just wish we had a pipe command.

 

 

EDIT:

 

here you can see the chamfer feature fails, because in one direction the distance is too big (3mm)

 

ch_feature_1.JPG

 

 

with 2.5mm it works - looking at the resulting outer boundary of the chamfer the minimal radius at the 'waist' of the 8-shaped cut is big enough, it should even allow a 4mm chamfer in that direction - but it does not..hence the work around

 

ch_feature_2.JPG

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