topic Re: Sketching arcs... in Fusion Design, Validate & Document Forum

Sketching arcs...

SA2020 — Fri, 21 Apr 2017 22:39:08 GMT

I've attached a sketch that I'm working on. The open section on the left side of the part is .138 wide and I'm trying to create an arc from each of those endpoints, winding up with a radius of .100. The arc rises above the work by .035.

I'm able to create an arc from each of those endpoints, but I can not control the radius that I want to end up with, .100. I select the right side face when I begin the sketch and when I do create an arc, it's out in space, not at the end points between the .138 width. I also can not control the .035 height that I want.

Any suggestions? After creating the sketch, I want to turn this into a solid. After I figure out the arc issue, I need to extend the cylinder down by .165.

Re: Sketching arcs...

etfrench — Sat, 22 Apr 2017 01:56:33 GMT

It would help if you used CAD definitions for directions and planes. Above could be on the Z axis or the X axis depending on how you view the drawing. In any case create an offset plane at the point you want the arc. Add a sketch to the plane. Project the endpoints from the original sketch. Use a 3 point arc, selecting the endpoints and any midpoint. Create a radius dimension on the arc and set it to .100. Note: The height of the arc will be 0.27619063". It is not possible to create a .100 radius arc with a .138" base line and have the height equal .035.

Note: This is shown on the XY plane, but it could just as easily be done on the YZ plane.

Re: Sketching arcs...

SA2020 — Sat, 22 Apr 2017 13:50:50 GMT

How do I define which plane I want to work in? I noticed that was my first challenge. Also, after defining which plane I want to work in, can I rotate or rotate to a different view?

This is the part that I'm trying to sketch and then create a solid for:

Re: Sketching arcs...

TheCADWhisperer — Sat, 22 Apr 2017 14:21:18 GMT

There are several dimensions missing in your latest image post.

Can you File>Export your *.f3d file to your local drive and then Attach it here to a Reply?

Whoever made the original - fudged on the given dimensions.

Re: Sketching arcs...

SA2020 — Sat, 22 Apr 2017 14:50:34 GMT

Those are the only dimensions that I have. I don't know who created it, but agree that it's confusing.

How did you create a solid for what you posted? That looks exactly like the isometric view that I have for this print.

Re: Sketching arcs...

TheCADWhisperer — Sat, 22 Apr 2017 14:57:24 GMT

@SA2020 wrote:

1. Those are the only dimensions that I have.

2. I don't know who created it, but agree that it's confusing.

3. How did you create a solid for what you posted? That looks exactly like the isometric view that I have for this print.

1. I don't believe this statement. I think you cut off the dimensions for the outside diameter (cylinder) and inside diameter (hole) in the image that you attached.

2. Well, I don't think so much as confusing as just plane wrong. I used the dimensions that are trivially easy to measure (R.1 and .035), the chord distance would be difficult to measure in the real world - and even more difficult to control. It is simply not needed (and wrong in the given image).

3. Have you gone through the Help>Learn Fusion and Getting Started? The modeling process is all recorded in the timeline (same as in SolidWorks).

Re: Sketching arcs...

SA2020 — Sat, 22 Apr 2017 15:49:19 GMT

1) OD is .570 and the ID is .375. I had those on my initial sketch, so I figured that was a given.

2) That's what I'm dealing with, I can't control that.

3) I have not done what you recommended. I was going to create a wireframe first, then extrude from there.

Re: Sketching arcs...

SA2020 — Sun, 23 Apr 2017 18:44:59 GMT

How can I finish the wireframe so that I can extrude from there? Or is there any easier way to do this?

Re: Sketching arcs...

etfrench — Tue, 25 Apr 2017 05:34:07 GMT

@TheCADWhisperer's method is the simplest, but this video shows the hard way anyway. Please note all of the dimensions I used were not correct

Re: Sketching arcs...

SA2020 — Wed, 26 Apr 2017 00:57:44 GMT

Thank you etfrench. I will spend some time and give it a try. Thanks again for the help.