Fan blade modeling

[jdmech]

Hi folks - 

Veteran Inventor user and now NEW Fusion 360 user (maybe).

I'm just getting my feet wet on this new release and pretty impressed so far.

I was wondering if there is a tool or function available to create a twist in a solid or component.

I realize that creating a loft feature is available but requires many steps in order to create a simple

DC muffin fan blade. I was trying to find a model aleready available but no luck so decided to model it myself.

30mm DC fan

Thanks! - JD

[sachlene.singh]

Hi JD,

I was modeling an auger recently and had the same question. I found this post by Nathan Chandler very helpful: http://forums.autodesk.com/t5/sketching-sculpting-modeling-and/helical-sweep/td-p/5186239

The way to currently model a twisted shape (e.g. blade of a fan) is by using a 3D sketch as a rail for a loft feature. I created the profile for the blade every 90 degree of twist, but you can experiment with how many you need to get the accurate shape.

I hope this helps,

-Sachlene

[NicolasXu · Accepted solution]

Hi JD,

There is a simple Fan model I once created to test Fusion (attached). I tried the insert workflow and no errors. I was using the Project to Surface to generate the 3D spline. Please feel free to check and see if it helps.

Best Regards,

[jdmech]

Thanks very much Nicolas - 

Very smooth model. I'll try your work flow.

Thanks! - JD

[jdmech]

Ok - so I examined your workflow and it's great, but leaves me with a question:

Q: When the fan blade sketch profile is projected to the cylindrical surface of the hub,

how does the projected line (colored purple) have a twist in it? You can see it at the right end where it

lifts up. After lofting, it clearly looks like a perfect blade with a twist. The line seems to act like it was directed to twist

on a rail.

Thanks - JD

[NicolasXu · Accepted solution]

Hi JD,

The projected curve (colored purple) is generated by sketch “Project To Surface” command. When we project sketch curve onto the cylindrical surface, we can specify the projection direction. In this case, the normal of the cylindrical surface is used (i.e. closest point). The twist is controlled by the normal of the surface. In the following screencast, we can see the projection direction is pointing to the center of the cylinder.

I’m not 100% sure if the shape matches the blade in real products, but the advantage of the Project command is Fusion can keep the association between the sketch curve and the projected result. 

I hope it helps, please feel free to let us know if any questions or feedback.

[jdmech]

Great explanation Nicolas - 

Thanks very much!