Why do I lose components after editing a sketch?

[mpulliam6CT22]

Hi,

I am really having a difficult time understanding Fusion 360 design logic.  I feel like it is at odds with how I work and the result is that I end up going around in circles, completely unable to draw a simple design.  I have watched a LOT of tutorials, they are very helpful, except that they are designed in a very linear process.  What I mean is that the instructors seem to know exactly what their design is, with the shapes already laid out and dimensions.  So everything works.

However, when I have to design something, I lay out the general shape, and then go back and add details, joints, change shapes, fiddle a bit, push/pull etc.

I completely wreck my design every time and have to do complete design do-overs multiple times.

For example, I just designed a platform bed.

I created a base with four sides and multiple slats.  Every piece was a separate component.  Every dimension was parametric.  Then after, stepping back and looking at it, I decided to change the shape of the very first side I created, adding a curve and a cut out.  So I edited the sketch and changed the features.

Then I extruded it and low and behold - I lost every single component I had created except for the one I was just working on.

WHY?

How do I keep this from happening?  It is not obvious what I am doing is a mistake, because particular problem hasn't happened before, I seem to just have natural instinct for finding the way Fusion 360 doesn't want to be used.

[James.Youmatz]

Hi @mpulliam6CT22,

Without seeing the model I can only speculate as to what might be going on here. My guess is the change you made might have had some downstream effect on your timeline that is causing some errors in the timeline. Can you share a public link to the model so I can take a peek and see what might have happened?

Also, based on what you are describing, have you tried experimenting with direct modeling as opposed to parametric modeling (with the timeline history). If you like to make changes as you go and aren't completely sure of the end result, then direct modeling may be a good environment for you! It allows the user a little more control over these edits as it won't recalculate pre-existing geometry. Edit: Just read that you said every dimension is parametric, so perhaps this might not be the best option then. Once I see your model I can make better suggestions. 

[mpulliam6CT22]

Thanks,

http://a360.co/2ctUdjB

No, I haven't used direct modeling because I don't understand the pros/cons.  It hasn't been explained or touted in any of the tutorials I've watched.

[mpulliam6CT22]

I don't understand why the public link takes to you to a render of approximately half of my design?

[mpulliam6CT22]

ok, it updates when I save it.

I see.

[James.Youmatz]

Hi @mpulliam6CT22,

So without knowing the changes you made, my guess is that the sketches you edited, caused some changes that made the joints invalid/made the components lose reference in your timeline. The timeline has warning messages on a few of your snapshots (the moved components) saying that the compute has failed due to joint conflicts. I don't mind working with you to solve these (I'd probably have to do a 1:1 session with you to see how it was supposed to be built), but I did notice in another post (http://forums.autodesk.com/t5/design-validate-document/no-alignment-suggested-by-geometry-could-be-f...) that it seems you have moved on past this. Is this model in a working state now?

Thanks,

[mpulliam6CT22]

Basically I made 2 components and a lot of copies.

I went back and changed the first component's sketch and everything moving forward disappeared.

It was easier just to re-make the 2nd component and remake copies than it was to figure out what went wrong first.

I just wanted to see what I was doing wrong for the future.  Maybe it was the joints.

The use of joints has been problematic for me, I keep using them bc I was taught it was the right thing to do, but I guess they can cause more trouble than they are worth in the design process.