Scaling body along specific axis

[jwatte]

How do I scale the cylinder in this picture along the construction axis I created?

The "non-uniform scale" option only allows me to scale along the primary axes of the coordinate system.

I'm OK with re-setting the primary coordinate system, as long as the object doesn't move in the world assembly (there are more components, hidden right now.)

I just need to scale the object along that construction line.

[wmhazzard]

As far as I know, you can only scale on the primary axis.  

[wmhazzard]

You could rotate the body, scale it and then rotate it back. 

[jwatte]

That's what I was afraid of. That's unfortunate.

I seem to recall Inventor had a "set work coordinate system" widget for bodies, and I sometimes used it.

3ds Max has that, for sure, and it's sometimes quite the life safer!

[jwatte]

Unfortunately, the scaling coordinate system rotates with the object.

I need to somehow rotate the vertices of the object, without rotating the coordinate system.

Maybe I can do some shenanigans with CSG subtracting an empty block from it to "bake" it somehow...

This is after 45 degree rotation. You will note that the "arrows" tripod is now in the right alignment, but when I drag an arrow, it actually scales along the "coordinate system tripod" which is still in the off-kilter direction.

[laughingcreek]

Your looking at the component origin (i think), it's still scaling along the global origin.

[g-andresen]

Hi,

all seriousness I would never have the idea to "bend" someting like that in any form.
Rework the design and you save yourself time and trouble.

günther

[MRWakefield]

We might be able to offer greater assistance if you could give us a bit more information. What exactly is your end goal?

Can you attach your f3d file?

[TrippyLighting]

---

@jwatte wrote:

3ds Max has that, for sure, and it's sometimes quite the life safer!

---

Your mentioning of 3DS Max has me wondering whether you are trying to apply a workflow that is often used in Sub-D modeling in a CAD environment where it is very rarely used.

When I work in Blender I scale thigs very often. However, in 30 years of working with CAD I do not recall ever using the scale functionality let alone a non-uniform scaling. 

Edit: I have used scaling in Fusion 360, but not to re-size a mechanical component. When you import a complex SVG it is easier to extrude your shape and then scale the solid body, rather than the sketch with the SVG. So the scaling functionality does have its use cases, but it is usually not used for re-sizing mechanical components, particularly not in parametric modeling software.

In this case, it might simply be better to use the Move tool with the "Faces" option.

then the orientation does not matter as faces will be moved along the main axis of the cylinder.

[chrisplyler]

I've never used scaling in Fusion. Not even once. I try to model stuff so that I can change whatever I want by editing dimension or parameter values.

If the component is jointed into an assembly, perhaps you can delete that joint, scale the body as desired within the component, and then rejoint it back into position.

[laughingcreek]

I'm thinking the salient point for the op ATM is understanding the difference between moving a body and moving a component.  We can get into workflow bashing next.

FWIW, I use scale at the end of many models b/c masters for investment casting have to be scaled up by a certain percentage to allow for shrinkage.  I need both an actual size model and the scaled up master. not going to model it twice. 

[chrisplyler]

Okay, that sounds like a valid reason. Is that why the OP wants to do it?

[jwatte]

So, I ask how I do X, and I get suggestions that "X is rare to want to do."

I agree! This is the first time I want to do X! (Where "X" is "scale along a particular axis")

But, in this case, the reason is for manufacturability. Specifically, this is a thin wall tube that flexes when clamped in workholding, and flexes back when released. I don't want to make a precision plug to shove in the middle of this, adding cost and complexity, when I can just measure the deformation (0.45 mm) and scale down (really: squash, as I need to expand along the other axis) the part along the axis of clamping to generate the appropriate toolpaths.

For what it's worth, I could also achieve this by writing a script that parses the G-code and applies the appropriate scaling, but doing that for circular interpolation toolpaths is a major PITA, and having Fusion do it is so much better.

So, can I go back to the original drawing, and apply the scale there? Well, the circular section of the tube actually comes from a mating part, so I'd have to finagle that somehow, but the bigger problem is that I don't want that drawing to be scaled, because that drawing is "as intended" whereas the scaling at the end of the part modifier stack is "for manufacturing."

[chrisplyler]

Ah, I gotcha. Thanks for that thorough explanation.

Soooooo... if it isn't truly scaled... might you use an ellipse, instead of a circle, from which to extrude the tube? Then you could, for example change the X and Y dimensions of the ellipse from, lets say 30mm x 30mm (which would be a circle anyway), to 29.55mm x  30.45mm, which would represent your deformed condition?

Just trying to brain storm here. Don't know if that's suitable or not.

[laughingcreek]

I didn't say it right in previous post.  it scales along the component axis.  when you rotate, you have to rotate the BODY and not the COMPONENT.  that way the body will rotate in respect to the component coordinate system.  

[jwatte]

Thanks for the suggestions.

I did, in fact, rotate the BODY, not the COMPONENT, when rotating. I had Selection Priority set to Body.

I don't want to use an Ellipse, for the reason I suggested in the clarifying post: the part should be "as intended" in the assembly, and I just need to temporarily squash it when making toolpaths "for manufacturing."

I'm going to do some experiments with re-creating the cylinder using intersection between a big block and the actual part, to see if I can reset the internal coordinate system, and then scale along the axis I want.

[laughingcreek]

So strange. Turning a body with respects to it's components origin works for me.  May be if we could see what your doing, or an example model maybe.

[Dreistein75]

Is there a "suggestion box" for Fusion? Because scaling along an axis not equal to x/y/z is not that unimportant I think. I came to this post because I have the same problem. I have a M6 thread and I want to 3d-Print it, so I have to scale it a bit, but the part is very wildly embedded into the coordinate system, so I must scale along two specific non-x/y/z-axis... 

The previous tip with "rotate, scale, rotate back" does not work, because rotating back the scaled object does not bring it to the previous location.

[TheCADWhisperer]

---

@Dreistein75 wrote:

I have a M6 thread and I want to 3d-Print it, so I have to scale it a bit,…

---

@Dreistein75 
In my opinion this is not the best or even logical solution for your problem description.

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

[g-andresen]

Hi,

If you want to scale a thread for 3D printing, this can be done with the Offset Face tool under MODIFY.

Screencast

günther