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Fillet edge of cylinder


Ken

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The cylinder I first posted didn't take the fillet. But here's my real project where it's not working. The cylinder is actually not straight. Both inside and outside diameters taper, as in "draft" for injection molding. Hopefully not too complicated for fillet? I've got many more instances that are more complicated.

fICNHYK.jpg

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Yes I had to use multiple extrude for both inside cylinder (the void) and outside. How else to produce a tapered cylinder? But more to the problem, why can't the resulting edges take fillet?

Is fillet very limited?

If so, what other method is available to ease the edges of compound solids?

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One way to form the cylinder is to draw your 2d wall section profile (just one side) and sweep it around a locus at the axis. 2d objects in Top/Plan. The sweep will emerge with axis parallel to the z axis. This shape will take the fillet. Or better, draw the fillets into the sweep profile.

Another way is to draw the inner and outer circles at bottom, convert them to NURBS (This makes a group containing 2 NURBS curves), Duplicate in Place, Raise the second set to proper z height, Rescale the upper group (or just draw the second set at correct radii). Ungroup all, Loft surface from bottom outer>top outer>top inner>bottom inner. In the Loft dialog, select Ruled, Closed, Create Solid, Keep Curves. This creates a Generic Solid which will accept the Fillet.

Post back if not familiar with these techniques.

-B ubbthreads.php?ubb=download&Number=10067&filename=Sweep.png

ubbthreads.php?ubb=download&Number=10068&filename=Loft.png

Edited by Benson Shaw
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Ken,

I think its because it sees each segment as a separate surface so often the segments won't be big enough for your fillet radius and it fails. Sweeps and solids are much better behaved. Benson's methods will work. You could also use a pair of tapered extrudes, subtracting one from the other to create the hole.

I don't think the multiple extrude object has been updated for many versions. It may not take advantage of the Parasolid engine (its a guess but nothing else produces facetted geometry in quite the same way).

Kevin

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Ken et al - there is a better and more effective way to model this:

Step 1 - draw the base circle.

Step 2 - use Tapered Extrude to get the base 3d object.

Step 3 - use Shell to turn the shape into a tapered tube.

Step 4 - use the fillet tool to round the top edges.

Step 3 Note:

- use the Option key to select the bottom surface.

- use the Shift key to add the top surface to the selection set.

The process is shown in the attached image and file.

Using the correct techniques can make a big difference to the modelling outcome in Vectorworks. The 3D Power Pack pages can show you what to use and when. Take the time to explore all of the information available and your modelling will significantly improve.

http://www.vectorworks.net/3Dpowerpack/qtexamples.php

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You select the surfaces that you want open.

First you select the bottom surface (depressing the option key allows you to select surfaces that are behind other surfaces). Then with the Shift key depressed you click on the top surface to add that to the selection set.

The attached image shows the tapered extrude with two surfaces selected.

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Ken try doing two tapered extrudes and then use Subtract Solid to form the 3D object.

With Tapered Extrude:

- the base 2D shape needs to be Layer Plane

- positive angles taper the object inwards

- negative angles taper the object outwards

To get a larger top and a smaller bottom you can also use a positive angle with a negative extrude. You would then need to move the inner 3D object upwards by the height of the extrude.

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With Tapered Extrude:

- the base 2D shape needs to be Layer Plane

Good tip, Mike.

For some reason, my document is drawing new lines, circles, rectangles, etc in Screen Plane mode by default. The Document Prefs / Plane Mode is set to Screen Plane or Working Plane. But the same pref settings in another document (or new blank document) defaults, as desired, with drawings created in Layer Plane mode. This is the problem causing my Tapered Extrude from not working.

What other factors influence the pref settings?

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