Unable to subtract solid from solid

[dtaylor]

I have these two solids. I want to subtract the long thin one from the round wide one. When I try, nothing happens. Any idea why?

manhole invert 3d.dwg

[fahim108]

Very strange indeed! ...how did you model it? ...I hope you didn't copy-paste it from an older version of cad?

[dtaylor]

i drew it from scratch in 2011 using cylinders and boxes and snapping them to needed points. i saved it as a 2004 version for the forum so more people could open it.

[JD Mather]

How far from the 0,0,0 origin are you modeling? CAD programs don't like to be far from 0,0,0.

 

I checked the geometry in a next-generation 3D CAD program and it reported problems with the geometry.

[JD Mather]

Unstitched, Refit, Stitched and all is well.

 

But I would ask how you are going to manufacture that - the cut results in an infinitely thin intersection. In the real world some cuts will break through resulting in a nasty burr. (actually all parts will show a buldge from tool pressure.

[dtaylor]

I ended up redrawing it and subtracting each section of solid as I drew it.

[dtaylor]

Its a concrete channel poured in the base of a manhole

[JD Mather]

Try this one (acisin).

 

I ended up redrawing it and subtracting each section of solid as I drew it.

 

Oops.

ACIS.zip

[dtaylor]

Thanks though. Any idea why a problem like that pops up?

[JD Mather]

Too far from origin.

solidhist

AutoCAD is a antiquated program for 3D solid modeling....