Manipulating some sketch line elements but not others

[fred.dV9264]

I'm a newish user. Been through a number of tutorials and the help but most so far are command based rather than technique based. Also I probably don't know the real terminology, hence I can't find an answer when searching.

Issue. I have a simple, single closed loop line in a sketch that I am using to create a revolved solid.

It becomes a funnel (replacement part for a broken one from a sausage stuffer)

Having got the base the correct size, I wish to make 3 different sized nozzles.

However, if I simply select the lines that make up the nozzle wall and move them outward, the lines that form the base section and the funnel angle move slightly and resize slightly resulting in a part that will not fit.

Clearly the way that the line/curve adjusts is not simple. Unfortunately I don't really understand the way that the line geometry works in the first place nor how the constraints on the line segments, (of which there appear to be many) work when modifying the line.

I've not changed any defaults that I can think of other than some of the display parameters so this model is created with a 360 default setup.

Can anyone advise if there's a simple way to achieve what I am after and why what I'm doing doesn't work and/or where I could find documentation/a tutorial on the principles of how the line works within fusion 360 so that I can make line manipulation easier in future.

Thanks.

[wersy]

You need to fully constrain the sketch.
Then you can edit all dimensions as you like.

[hamid.sh.]

I don't see any dimensions added in your sketch. Anyways, if you keep the sketch simple, leave fillet and offset to solid tools and make a fully defined sketch it will be pretty easy to change sizes:

File is attached, please take a look at my sketch and timeline.

[fred.dV9264]

Thanks, but having looked at your quick sketch / solid either I'm misunderstanding or I didn't explain well enough what I am after.

By fully constrain I assume you mean lock all the parts of the line together in this instance - as I can't move individual pieces of the line in your downloadable sketch.

What I want to achieve is being able to move the 80mm section away from the revolve central line (to increase the funnel spout diameter), while the 8 mm section stays exactly where it is  (in both x and y directions, so that the part will fit in the main tool cylinder and the retaining nut) while the "angled" section of the funnel adapts (i.e. changes length and angle as required).

I had assumed that moving some sections of the line would do this automatically ( a bit like visio does when moving line segments)  but this doesn't seem to be the case with what I have here. With yours I can't modify anything.

I'll go look up constraints later this afternoon if this is at all possible but pointers to how gratefully accepted.

[wersy · Accepted solution]

Another way could be to use surface.
Then you need only a single line.

Rotate it in surface mode

Thicken it

[wersy]

As I have already described.
All dimensions can be changed independently.

[TheCADWhisperer]

@fred.dV9264 

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

You must have missed something in the Tutorials.

Blue (unconstrained) lines should drive you crazy..

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@fred.dV9264 wrote:

I'm misunderstanding 

 as I can't move individual pieces of the line in your downloadable sketch.

What I want to achieve is being able to move the 80mm section away from the revolve central line (to increase the funnel spout diameter)…

With yours I can't modify anything.

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You “move/modify” by editing the dimensions.  Absolutely predictable and robust.

Edit sketch.

Double click on dimension(s) to edit.

[davebYYPCU]

Your sketch is not stable, so moving one part can have unstable results.

with correctly placed Constraint and dimensions, you can change the mouth size, the rest has to be able to adjust, 

In the examples given I would not specify the funnel angle, just the length / height of each Cylindrical segment, and the overall length - Changing the outlet opening to X will change the funnel angle, but not change the mouth end.  @Anonymous.sh Sketch is as I would start with, you can add the Offset and fillets as an optional sketch workload.

Terminology for that is changing parameters in fully defined sketches.

Might help....

[fred.dV9264]

Hmmm, I've tried replying twice (before I accepted a solution). the system previews it, accepts it and displays it, then it isn't there when I go back.

Any idea where I can go to ask for support on the forum??? Nothing obvious.