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RIB

The Rib tool is very valuable if you want to create a rib, especially if one or more of the contact surfaces are non-planar (e.g. on a mold boss). When you create a rib, be sure to select the tangent surface.<?:namespace prefix = o ns = "urn:schemas-microsoft-com:eek:ffice:eek:ffice" />


I tried to load the graphics but ran out of space. Here is a zip file:


2006-10-04_080757_ribCreation.zip
 
A rib is just a special kind of extruded protrusion, commonly used in areas where a part needs to be fortified or where you want some kind of brace-like feature to increase structural integrity.


First, create a sketch for the shape of the rib. This sketch has to be an open sketch, and must attach to geometry in your model, so that geometry has to be in your list of sketch references.


After creating the sketch, with the sketch still selected, click on the Rib tool. You can add material on one side, the other side, or symmetric about your sketch. Make sure that the yellow arrow indicates that material will be added to the inside of the sketch (for some reason, 99% of the time when I create a rib, the arrow points to the outside of the sketch.


Voila. Your rib will be created. Now, the big question is, why use a rib instead of an extrude? Well, there are a couple of narrow circumstances.


First, since the rib is an open sketch, it will follow the shape of the geometry it is attached to. But that's true for open sketches in general, regardless of the Rib feature.


Second, an extrude adds or removes material normal to the sketch plane. Ribs have a special quality in which the "thickness" surface follows the shape of the feature it is attached to.


Case in point: let's say I have a part which looks like an extruded L. An extruded protrusion and a rib will look the same. But instead, let's say my part is a flat horizontalplate with a cylindrical protrusion sticking upout of it. If I create a rib consisting of simply a straight line from the flat plate to the cylindrical surface, the "thickness" surface will be rounded just like the cylinder, as opposed to flat as you would get with an extrude.


That, in essence, is the difference between extrude and rib. I agree with Bart. Probably 99% + of the time an extrude will do you just fine.


Dave Martin - Nx Rev
 
I wish rib be available in assembly mode with welding option.


In part mode it is only good for analysis purpose.


Israr
 

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