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3D Subtract Creating 2 Non-touching solids
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* June 28, 2019, 05:30:14 AM
I really apologise for the run of questions.  I am trying not to ask much as I am aware that it is not your job to teach me TurboCAD.  I am however well over a dozen hours into this so I feel I am generally doing quite well!!!

I have modeled the inlet path for a car engine from the air inlet horns/trumpets to the end of the inlet manifold.  The result is a series of 3D ACIS solids that I am happy with.  In order that I can load this model into a CFD program (more steep learning curves lol) I need to create a solid from the internal bore of these solids i.e. make a solid that represents the airflow area.

What I have tried is to put a solid cylinder around the model such that it is fully encased.  I then 3D Subtracted my model from the large cylinder.  That resulted in a single solid that was made of 2 non-touching parts.

To remove the excess solid i.e. the outer part of the newly formed solid, I exploded it, selected the outer bit and deleted it.  I thought I was doing pretty well until I noticed that TC was now treating the remaining part as a TC Surface.  I tried to convert it back to a solid but it ends up being very faceted which I don't want.

I assume I have approached this in the wrong was somehow?  Maybe the way I created the internal 'airflow' model?  Maybe there is another way to remove the excess without exploding (and without creating a million 3D objects to slowly 3D Subtract the rubbish away)?

I would appreciate your thoughts....

WEBER DCOE 50 Inverse.TCW is pre-3d Subtract
WEBER DCOE 50 Inverse2.TCW is post-3D Subtract

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June 28, 2019, 05:35:25 AM
#1
To remove the excess solid i.e. the outer part of the newly formed solid, I exploded it, selected the outer bit and deleted it.

This is what did it.  To separate (or remove) two non-touching sections of one ACIS Solid, use the 3D Slice command.  There are several options; the simplest is to find a view that presents an open space between the two where you can draw a straight line (two clicks only).  After that, you can delete the undesired part.


Jeff

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TC Pro Platinum 2019, 2018, 2017, 2016 & 2015 (all with LightWorks & RedSDK) & V21
System: i7-5820K @ 3.30GHz, ASRock X99 Extreme4, 16GB DDR4-2133 RAM, Gigabyte GTX 970, Samsung NVMe SSD 950 (256GB), Windows 7 Pro (64-bit) SP1


* June 29, 2019, 12:10:28 AM
#2
That would work if the surfaces were straight but mine are angled and curved.  Guess I could pick away at it bit by bit but that is what I am trying to avoid.  Maybe I have not understood you.

I was looking for a way to make the thickness of my original object bigger on the outside then I could 3D Subtract.  Yet to find a way to do that though......

** EDIT **
I have removed most of it.  I cut the 2 part solid into slices depending on its profile i.e. a few sections have straight edges, a few have straight but angles and only 1 in an angled/compound profile.  I created a temporary cylinder then used that to 3D Subtract.  I am yet to work out how to do the bell mouth bit but still working on it.
« Last Edit: June 29, 2019, 01:01:07 AM by MK1_OZ »

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June 29, 2019, 01:14:52 AM
#3
There are a variety of ways to remove pieces of a 3D object.  The 3D Slice command has many methods (Slice by Line, Slice by Plane, Slice by (ACIS) Surface, Slice by Workplane and Slice by Facet).  You can also create objects that surround the volume you want to remove and 3D Subtract.

It may even be useful to use the part of the object you want to keep as a template for creating a new (clean) object.


Jeff

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TC Pro Platinum 2019, 2018, 2017, 2016 & 2015 (all with LightWorks & RedSDK) & V21
System: i7-5820K @ 3.30GHz, ASRock X99 Extreme4, 16GB DDR4-2133 RAM, Gigabyte GTX 970, Samsung NVMe SSD 950 (256GB), Windows 7 Pro (64-bit) SP1


* June 29, 2019, 05:47:48 AM
#4
Cheers.  I got there in the end.  Lots of slicing and 3D subtracting then redoing it all due to seeing some weird surface artifacts.  Reasonably happy now.  Many thanks.

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