Creating a solid from a empty core

[Jimmy111]

I do a lot of CNC milling of molds for foundries. Lately I get a lot of models that need cores and they are made without regard to the inside dimensions. Usually I explode them and break them down as far as I can then delete all but the inside surface then reloft the geometry as a solid. More and more models are coming with very intricate cores.

Does anyone know of an easier method of creating the solid core.

Attached is a simple model of a simple part. How would the inside hollow area be created as a solid?

Thanks

Core.dwg

[JD Mather]

Something like this? Explode, delete, Patch and Sculpt

 

 

or this

http://home.pct.edu/~jmather/content/CAD238/AutoCAD%202007%20Tutorial%207.pdf

 

in later versions there is the surfsculpt command that should make all of this easier.

[Jimmy111]

Thanks. Ive seen the Autocad 7 tutorial before. My main concern is inside cores.

How did you do the top one?

[JD Mather]

Explode the solid. (copied first)

Delete the outer surfaces.

Patch the end holes.

Sculpt the surfaces to form solid.

 

I tried to attach the actual file (as in the image), but it was too large.

[Jimmy111]

Can you do this with Autocad 2010?

I can copy the inside surface but then how would you turn it into a solid. How are the ends closed especially if it is an irregular shape?

Thanks

[JD Mather]

I am not familiar with 2010 - do you see Sculpt as in image above?

Do you see Patch as in image above?

[Jimmy111]

No. I tried the comand line comands and no such luck either. I know 2013 has better capabilities but dont want to upgrade at this time.

[Jimmy111]

So no sugestions besides upgrade?

[JD Mather]

For really simple stuff you might use Thicken.

But I recommend for this type of work you upgrade to a modern MCAD program like Autodesk Inventor.

 

I hesitate to mention that free Inventor Confusion has Delelet Face and a Sculpt commands.

http://labs.autodesk.com

[Jimmy111]

I have Inventor 2010. Its just that most of my work is in Autocad and most of my customers use autocad and things need to be compatible.

[SEANT]

Copy the object 100 units to the left. Use SolidEdit on the original solid to delete the inside surface. Move the copy back to the previous position. Subtract the copy from the original.

 

Selecting the two solids during the Subtract operation will be a little tricky, but if everything works properly, the inner cavity should remain as a solid.

[Jimmy111]

Smartass.

I dont know why i never concidered deleting the face... It worked perfectly for a semi simple one.

Thanks a bunch. Saved me a ton of time.

[SEANT]

... It worked perfectly for a semi simple one.

 

 

No doubt.

 

This procedure may prove inadequate for more complex Structure/Cavity arrangements; certainly with not so regular end faces.

 

The task is interesting, though. Perhaps there are simple step to build the structure up to facilitate a breakdown. Do you have any examples of more complex Structure/Cavity models that can be posted? If a viable process reveals itself, I’ll try to convert it to automation.

[Jimmy111]

Ok here is one. Give it a try.

LT&1 intake.dwg

[JD Mather]

I have Inventor 2010. Its just that most of my work is in Autocad and most of my customers use autocad and things need to be compatible.

 

Inventor reads/writes dwg file. Customer can read the dwg fine from Inventor.

 

See attached Inventor dwg file LT&1 intake1_core.dwg

 

Or in later versions of AutoCAD Patch and Sculpt right to left in the image (same thing I did in Inventor).