Equivalent SW Co-radial constraint in Fusion

[ehlertk]

Hello!

I am relatively new to Fusion, but I have a moderate understanding of CAD modeling from years of interspersed use and teaching. I am a faculty member who teaches modeling to freshmen and we need to use 360 because it is both PC and Mac compatible while also being accessible with the student's university credentials. In an effort to make the modeling more exciting to students, I wanted to convert the basic instruction on useless parts that are essentially thought exercises to something they could connect to. I decided to move to modeling a Rubik's Cube. 

I am trying to replicate a model from a SW instructional video here https://www.youtube.com/watch?v=hu9ajQ3giP0 in Fusion 360.  However, there is a step in the instructional video I can't seem to replicate in Fusion. 

At around 11 minutes, the creator sets a "co-radial" constraint for an arc in the sketch. The arc is set to be co-radial to a spherically cut surface from a previous revolution. This allows the second extrusion to smoothly abut to initial model as seen in the screenshot below (if you start at 11 minutes, you can see the whole process). 

In Fusion, I've tried to use the concentric and tangent constraints but these fall short of what I need (the outer radius of the inner wedge to be smoothly attached to the inside of the spherically cut cube). File is here: https://a360.co/4bqgR8y 

Am I missing something? Is there a different way I could be setting up this part to leverage the tools I have access to in Fusion? 

Thanks for your help!

[TheCADWhisperer]

@ehlertk 

Here is a trick that I use in SolidWorks when something doesn't constraint as expected (same trick works in Fusion). Click and drag unconstrained geometry and observe.

Looks like Coincident Constraint between the center points would be the logical choice. Just like in SolidWorks.

[ehlertk]

I appreciate the suggestion, but I think I wasn't clear with what I need. Here is another image, even after taking your advice, dragging the center and making it coincident. The goal is to get the intersection of these two shapes. Because my extrusion is straight but the wedge is spherical, there is a gap between my extrusion and my cut shape which is not something I want. I can't just create the extrusion profile and run revolved cut for the wedge because I need the inside radius to have a straight extrusion. 

[TheCADWhisperer · Accepted solution]

@ehlertk 

Your sketch does not match the sketch shown in the video (and isn't needed - the SolidWorks user doesn't know how to use SolidWorks judging only from the video).

I will Attach corrected sketch in a moment.

@ehlertk 

Turn off the visibility of the Analysis after examination.

I could have simplified this further as the sketch isn't even needed, but I don't want to confuse the issue.

[TheCADWhisperer]

@ehlertk 

Would you like to see how I would have modeled the part? (In both SolidWorks and in Fusion.)

[TheCADWhisperer]

@ehlertk 

Did you figure this out?

I expected there would be additional questions.

[ehlertk]

@TheCADWhisperer 

Thank you for your help! With classes and meetings, I was just able to return to this to see if your solution was what I needed. I was able to test it out and get it to work. 

Thanks again for your willingness to help and share your insights!

[TheCADWhisperer]

@ehlertk 

I taught CAD for 30 years.

When I get a chance, I will create a video of how I would do this geometry.

Check back.

[TheCADWhisperer]

@ehlertk 

[ehlertk]

Thank you @TheCADWhisperer! This is great!