Trouble Creating a Shell with a Loft

[Anonymous]

I created a lofted object.  It will not respond to the shell command.  I can not select the object when the shell window is open.  No error message.  It is a simple form.  No cuts, sections or additional features.  Thanks.    

[TheCADWhisperer]

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

[Anonymous]

I think the model is attached.  I have not done this before.  

[TheCADWhisperer]

You have a Surface Body, not a Solid Body.

Perhaps Thicken is what you want.  (see attached file)

Actually, after taking a second look - I recommend that you go through the Tutorials and then come back and try this part again.

Your Sketch1 is not fully defined?

Your geometry lacks symmetry that I would expect to see.

I can't help but wonder if a simple Revolve of a single circle would return the geometry that you need.

[Anonymous]

Is there a way to convert a surface body to a solid body?  I am looking for a uniform wall thickness.  

I have been through quite a few tutorials.  Which ones do you recommend for this problem?

What do you mean by "not fully defined"?   This is a test run.  Most of the features after the history marker are obsolete.  

I can fix the symmetry.  The edit form command is not always consistent.  I may have to mirror one good side to get a match.  How would i produce the bulge by revolving a single circle? 

Thank you.   

[TheCADWhisperer]

---

@Anonymous wrote:

1. Is there a way to convert a surface body to a solid body?

2. What do you mean by "not fully defined"?  

3. How would i produce the bulge by revolving a single circle? .   

---

1. See the file that I attached.  Thicken will convert from surface to solid.

2. I can drag geometry all over the screen.  As a machinist - first thing I expect is absolute datums.

3. I assumed the bulge was an anomaly since it was not symmetric.  But how would the mold for this be made in the real world. Could this be a combination of a torus section and a sphere?

As a machinist - I try to design for manufacturability (but it might have been hand made "art").

[Anonymous]

1.  Thicken seems to work.  Why does thicken work and not the shell command?  

2.  The distances to the origin are correct.  I have trouble telling when a dimension is locked.  

3.  The bulge is intentional and will be controlled.  It is not spherical.  The spline is also not a single radius.  

4. For manufacturing, think castings, which we have used, and forming dies which we are designing.  

Are there problems with lofted models?  According to the tutorials, I should be able to modify this like any other model.  I have tried to extend tangents on either end of the elbow and they are distorted or incomplete.  There are many other features which need to be added to this shape.  Their form and locations are critical.  So far this is not user friendly.  

[JDMather]

---

BbrownME1 wrote:

 So far this is not user friendly.  

---

I would expect significant training/experience before tackling what I think is the geometry that you are after.

Sketch1 is particularly troubling to my way of modeling.

[TheCADWhisperer]

---

@Anonymous wrote:

2.  The distances to the origin are correct.  I have trouble telling when a dimension is locked.  

I use the Origin as my dimension datum - just like out on the shop floor on lathe or mill.  The first thing I do is establish 0,0,0.

Turn on your sound to see the issue that I am seeing with Sketch1.

[Anonymous]

The straight lines you see are reference locations for future features that have not been added yet.  Feel free to change them to reference lines and constrain them if it helps or erase them.  

The spline is not a radius.  It is a specific arc and the curve changes continually.  (26.865 along one axis, 23.1 along the other.)    I can assure you that we can set up the machine to produce this part.  It is creating an accurate model that is the problem.  

[TheCADWhisperer]

I do not see a spline in Sketch1.

I do see an arc with a radius of 26.836621518

[Anonymous]

Recheck the dimension at different points on the curve. It should not be a fixed radius.  If it is, I will have to correct it.  

[davebYYPCU]

Back to thicken / shell question, 

the modelling area area is for solid models, the patch area for surfaces, and are sort of task specific, 

both areas can be accessed at any time, for the job to be done, but the shell command is not available in the Patch menus, and only creates consistent wall thickness from a solid.  

The thicken command is available in both menu sets, saves a bit of area swapping, or some flexibility.

Might help...

[Anonymous]

Thanks.  My first test, I created a cylinder and used shell.  It worked perfectly.  When I go to sculpt, is that actually under patch?  

[davebYYPCU]

T-Splines are hybrid

Has its own area, similar to sketches, edits are inside the box, when you close the box, it is available in other areas.

By hybrid I mean, that they create either, solid or surface, if a form body is closed it will be solid, if it is not a closed body it will be a surface.

I have thought of exceptions but that is the generally speaking description.

[TheCADWhisperer]

---

@Anonymous wrote:

Recheck the dimension at different points on the curve. It should not be a fixed radius.  If it is, I will have to correct it.  

---

In 30+ years of working with geometry - I have never seen an arc with more than one radius. It is what it is. Doesn't matter where I check - the radius is the same.