can't move a sketch

[Anonymous]

I'm struggling to do very basic things in Fusion 360, including moving sketches.  The instructions here do not work for me at all:
http://fusion360.autodesk.com/resources/akn/view/NINVFUS/ENU/?guid=GUID-FFD25CD3-0707-429E-B0E6-B7F9...

For example: I sketch a centerpoint circle.  Then I want to move that circle.  I right click, select 'move,' and the dialogue pops up saying "no selection."  The circle is no longer select-able.  WTF #1.

I change mode from "bodies, sketches.." to "move sketch objects" and now I can select the center point and get the manipulator.  Progress!  Then I move it along the x axis, lets say 300mm, click ok, and... nothing happens.  WTF #2.

Going back, I find the only change I CAN make is rotating the circle about a moved pivot point.  For some reason that actually moves the sketch.  WTF #3.

Clearly I'm missing something...  

[Anonymous]

Yes, I'm aware of the maths involved with conics. I had a go at creating a conic section and was immediately struck by the limitations of that option. As jeff indicated in his advice I think using a .csv file and splines will be the better option.

[Anonymous]

Regarding the overlapping lines, I wasn't aware of how to use the dimension option. And it's still not clear to me how I enter coordinates to define a point in a sketch. I'm resigned to spending a day trying to figure out how the developers conceived of that process.

Back in the 1980s we developed a language for defining the geometry and wrote a compiler to parse the user geometry definition and create what Fusion 360 calls the "sketch". So I am familiar with the concepts. My point is that even that level of knowledge is not enough to alleviate the feeling of struggling with the UI.

On this community there is an additional struggle that I feel which is shifting the blame for inability to use the UI back onto the Noob. I've been involved in a lot of tech developments and that shifting is a really bad habit that gets in the way of continuous improvement of the product.

Of course you can dismiss me and my experience and pursue a feeling of self-satisfaction if you like. Up to you.

[TrippyLighting]

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@Anonymous wrote:
...I think using a .csv file and splines will be the better option.

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That really depends what accuracy in your result you are looking for. At the current time, whatever we propose will be a workaround.

If you do go ahead with the .csv workflow, try to limit the number of points. It will likely require some experimentation.

oNce you have the points in a sketch in Futons 360, you will need to use a fit point spline to connect the "dots".

A fit point spline in Fusion 360 is a 5-degree multi-span spline. With too many points the curvature of the curve will not be smooth and look like a saw-tooth profile.

[Anonymous]

I am designing a parabolic dish antenna for a wavelength of around 20cm. My accuracy requirement is 1/10th of a wavelength, so 2 cm accuracy in a 4m diameter. The spline fit will be sufficient.
Thanks for the advice about the number of points. I'll try around 10 points for starters and see how that goes.

[Anonymous]

Moving onto the actual problems within Fusion 360, I have attached the geometry, ie "sketch", of a couple of imported splines. I have a short spline which I intend to be part of a hub, and the longer spline will be the surface of the larger parabolic surface. Yes they overlap, but the shorter spline and longer splines will have different profiles in the xz planes and during the design of this although the end products was overlap, they will overlap on the journey. Perhaps you might enlighten me on why overlapping geometry is not a good idea.

However, my main issue at the moment is why the splines do not appear to be in the xz plane, and I can't select the z axis for a surface revolution around the z axis?

The other thing is, now these curves start at 0,0,0 and I can move them. I tried them at different locations as well, but left them here as this is my prefered location if that's possible.

[Anonymous]

Sorry Jeff, I meant the previous response to be a reply to your earlier advice.

The splines from the import of the CSV are attached. 

Just trying to figure out how to select the z-axis for a surface revolution of the splines.

For some reason Fusion 360 doesn't see the splines as being in the XZ axis and I'm struggling with how to put the curves in that plane or select the revolution axis.

[TrippyLighting]

 You can revolve this without having that on the XZ plane:

[Anonymous]

I can replicate everything you did except for retaining the surface when I hit "ok" for the surface revolve. Then I get a message "1 error(s) Revolve1, The path is tangent to the profile. Try adjusting the path or rotating the profile"

I tried importing the same spline into the xy axis and can revolve an axis. 

Then all I need to figure out is how to rotate the spline sketch into the xz axis. Or alternatively rotate the resulting body.

[TrippyLighting]

I should have attached he model to my last post. Here it is.

[Anonymous]

Thanks, I imported that and have the dish now. Unfortunately I can't replicate how you did that at the moment, so doesn't help for future issues for me.
I can import the spline into the xy plane. Just wondering if there is any way to rotate that sketch into the xz plane?

[TrippyLighting]

After extruding the spline, make sure you hide the sketch(folder), when you select the profile for revolution you don't select the sketch, but the bottom edge of the extrusion.

Not sure this is the issue but it's worth a try.

[Anonymous]

Ok, that was the problem, I was selecting the sketch not the bottom edge of the extrusion.
After I have created the surface I am left with the extrusion as well as the surface. Just wondering what you recommend about removing or deleting the extrusion? At the moment I have removed it only.

[davebYYPCU]

Remove is correct,

Delete will also delete the dish.

Might help....

[Anonymous]

This is the start of the next step on this and I'll possibly move to another thread or start another topic.

So I have created a "component" with the parabolic surface and hub, and I can move that about as a single unit (I guess that what Fusion360 means by component?).

Now I want to create a parabolic square section. I did that based on the parabolic spline sketch and it seems to want to go into the root Bodies folder. I then create a new component called "spokes" and try to copy (drag or copy into group, don't know what is best to use) but it won't go into the Spokes component. So I do the usual google of the problem and I am finding old posts that seem to imply that there are limitations on rearranging the elements of the component hierarchies. Is that right? Or can the hierarchy (see attached) be arranged, that is after the spoke square section has been created can it be sent to the spokes component---as the first of a number of similar spokes? 

[TheCADWhisperer]

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@Anonymous wrote:

Back then our users were the machinists that operated the mills and lathes on the shop floor.

It would have been very easy to consider ourselves superior to the machinists, ...

...or advising against using (0,0,0) (the natural place to want to put a mathematical function) as the root for our designs. 

@Anonymous 

Back then when I was out on the shop floor first thing I would do when setting up a mill or a lathe was to establish the 0,0,0 datum.

When I finished a part - it was removed from that datum and moved to wherever in the world (literally) necessary to assemble with mating components.

I do the same thing in any CAD.

I teach the BORN Technique in CAD. The Origin is an absolute datum.

The component can be moved in the virtual CAD world to wherever is needed to assemble with other components.

Geometry is geometry. 

[TheCADWhisperer]

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@Anonymous wrote:
I may run my attempts at my design in parallel with another CAD product and see which way I will go. The nature of help I get from Autodesk and the community will be an important factor in deciding which way I should jump.

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@Anonymous 

You might also check out Autodesk Inventor Professional.

Inventor Professional includes >> 2D Equation Curve and 3D Equation Curve << functionality and much better integration with Excel.

>>The Inventor Professional user forum<<.

BTW - Inventor Professional also includes Sketch Block functionality that would make this entire thread discussion unnecessary if this basic functionality was in Fusion 360.

[Anonymous]

Thanks, that's useful. It does pay to look more broadly at a problem and see if we are even in the correct product. Fusion 360 was recommended to me and it looked like one of the leading products in CAD/CAM and that's why I am here. However, it may be for the scientific-engineering applications I am looking at that Inventor may be a better option. I will investigate further.

[Anonymous]

It's interesting that the original problem I was having was that I couldn't move the spline and I was advised not to put the origin of the parabola on (0,0,0) as that would constrain the curve and I wouldn't be able to move it. But when I followed the other bit of advice about importing the spline coordinates that problem went away. I now have a spline parabola that starts at (0,0,0) and I can move it. So it seems to be a non-issue. There was something about the way I was defining the coordinates that caused the original problem that has now gone away. So it's a non-issue now.

Your comment about BORN is also interesting. I was just watching a Youtube video about BORN. That takes me back to an earlier comment someone made about "explaining a user interface". It's really important that the developers tell the users what design philosophy they are using for a product. Is it BORN technique? Then we need to know that so that users and developers are on the same wavelength.

[TrippyLighting]

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@Anonymous wrote:
 It's really important that the developers tell the users what design philosophy they are using for a product. Is it BORN technique? Then we need to know that so that users and developers are on the same wavelength.

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The BORN technique applies pretty broadly across all history-based parametric design software.
Not sure what video you watched but here's one I can recommend.

Following this link is an older PDF predating @TheCADWhisperer's video that also explains the BORN technique.

[Anonymous]

Yes, that's the video. Just saying it might be worth pointing Noobs at the material about BORN. Although I had been involved in software development in CAD/CAM in the early 1980s I don't recall that term from back then.