Hello i went through a guide with torodial bend : Tutorial: How to model Tire in PTC Creo Parametric and show design intent - GrabCAD
I did the basic part but what i wonder is how he does step 11 and build on (extend) the sides of the tire. I cant choose the side or anything what is best way to do? he says to the step 11 description that he used revolve cut etc, but should you instead before making the Bend have a wider part where the sides are not with pattern like this:
STEP 11 - HIS PART IS TO THE LEFT, MINE IS TO THE RIGHT
He's just saying you can add any other feature you wish at the end. It looks like he added another revolve to add in the extended sides. There are a few ways you can do similar things in Creo. You can also look at the Flatten-Quilt / Flatten-Quilt Deformation commands. This offers another potential method for achieving similar geometry.
Toroidal Bend is one of those rarely used niche functions in Creo. Some people make them to just to demonstrate their prowess but you rarely see anything created with them other than a tire. Literally, they may as well have just called it Tire Feature. However, flattening a quilt and then bending back solid geometry created from it can yield some pretty amazing results. I'd encourage you to give it a try!
Hello brian and thanks for the answer. okey but how did he use the revolve to extend the side? and make the revolved geometry be coincident with the tire geometry (as you cant select the side of the tire where his revolve extends)
Ok thanks, I will look it up
We use toroidal bends all the time. It's a good method to create bent metallic parts that have non-trivial features installed in them in the flat pattern. Stuff like tapered regions, multiple depth pockets, and countersunk/counterbored holes. These types of geometries would be very difficult if not impossible to do without this feature.
You're saying "non-trivial" features - which, I assume, means you care about them. What about the deformation you're getting with the toroidal bend feature though? You can also bend and twist things using Spinal Bend or any of half a dozen Warp features. The problem is that you're losing some fidelity and locational accuracy with the bending feature.
If you're controlling features precisely in the flat pattern and then bending with Toroidal Bend, I don't think you're really gaining much over other forms of bending. You can do some incredibly complex things using deformed quilts, too - but ultimately once the thing is bent into a strange shape, accuracy is lost.
Am I missing something?
The final geometry we are looking for is the bent shape. The deformation is what happens anyway. I.e. a countersunk hole, simple in the unbent part, becomes a complicated Dali-esque shape in the bent part. It becomes a bit troublesome when trying to assemble screws and such, but that's the price we pay for not having to drill and countersink the holes on a bent part. The accuracy of the geometry is sufficient for what we are building.
Let's start with a simple example: I have a toroidal bent which becomes a bushing. In the 2D drawing I want to have the bushing and the unbent feature. How can I do that?
What I usually do is build the model as the flat part first with features maybe like this:
- Main shape
- Holes and other added features
Then I define the toroidal bend.
I then define a family table, with entries that are called something like "part-bent" and "part-flat". I put the toroidal bend feature in a family table column, and make it "Y" for the bent one, "N" for the flat one.
On the drawing, you bring in the flat instance, define all the dimensions and stuff for it, then add the model for the bent one, and define views for it. You can have as many models as you want in a drawing. It just gets a bit tricky when you're setting view scales - you have to "set" the current model to set the scale for the views that show it.