Hi,
simple issue : substracting solid from solid and keep the result solid (!)
Any idea ?
TIA, Oliver.

Hello Oliver,
>> substracting solid from solid...
Dosen't look like two solids;-) Please explain: What is base object, what is substractor and what should the result looks like.
And if the file is not confidential - please post it - so everyone can have a look and maybe find a solution.

Have a nice day
Karsten

p.s.: Und ich dachte, nur der rote Baron kommt aus der Sonne ...

Hallo Karsten,

>> Dosen't look like two solids;-) Please explain: What is base object, what is substractor and what should the result looks like.
>> And if the file is not confidential - please post it - so everyone can have a look and maybe find a solution.

Base object is the cab, cut object is the cube, both solids.
Purpose : Cutting the window(s) out of the cab side(s).
3dm attached.

mfg Oliver.

>> p.s.: Und ich dachte, nur der rote Baron kommt aus der Sonne ...
nein, auch unsere Jäger in der BoB

The cab appears to be very, very thin, with two tested overlapping side pieces being the same to 7 decimal points, (or maybe more).
So maybe scaling up everything by 10 to the power 7 or so would help?

- Brian

Edit, scaling by 10000000 did not reveal any difference in the dimensions of two tested overlapping side pieces of the cab, so there seems to be no thickness,
so the "Solid" designation seems to be faulty, or else ???

I did not try 15 decimal places :-)

How is such a thin cab to be manufactured?
Even gold leaf only thins down so far:-)

Hello Oliver,

I think Brian is right! The wall thickness seems to be lower than the internal tolerance of Moi for identical points (I remeber to read 0.005). Is it created with Moi or an import?

-Karsten

Hi Oliver, yes it won't work well to have such an extremely thin wall thickness, if your thickness comes too close to around 0.001 units it will confuse the intersection process because it will consider both sides of the solid to be close enough to one another that they are considered overlapping each other.

- Michael

Thank you, guys !
What would be the best way to increase the cab wall strength ?
Tried Shell command, but to no avail.

The solid is difficult to work with, but after about 8 repeated tries:

There appears to be actual bevel thickness on the delta side of the cab solid.
There are two copies of the cab. One has a skinny delta shape, which will not quite match up with the other cab.
There would be a narrow sliver of a gap, between the "wrong" surfaces, or overlap, near or at the delta shape.


First of all, color the box magenta and hide it.
Secondly, Separate the solid cab.
Pick the "inside" surfaces, one by one, and color them say red. Join the red surfaces.
If more than one red joined surface occurs, some of the surfaces are the wrong ones, with a narrow gap or overlap, so swap a surface at or by the delta,
until the red surfaces are "continuous", without gap or overlap, and will join to one joined surface.
Hide the red surfaces.

Color the remaining "outside" surface say cyan. It should Join to one surface, if the red one joined to a different one joined surface.


Now the magenta box will trim the red cab.
The red cab will Offset Shell just fine, either outwards, or Flip inwards.

- Brian

It's not more simple to make a simple scale *100 for all objects ?
Make the Boolean operation
Then Scale * 0.01

Hi Pilou,

re:
> It's not more simple to make a simple scale *100 for all objects ?
> Make the Boolean operation
> Then Scale * 0.01

That's probably not going to help for this case - on one side of the object there doesn't seem to be any thickness at all, the inside and outside surfaces on one side are directly overlapping on top of each other. That kind of self-intersecting object will confuse the booleans.

@ Oliver - does Brian's file above solve it for you?

- Michael

Thanks again, Brian, Pilou and Michael !
Unfortunately, Shell didn't work for me, from a clean joined surface
I get a messed up joined surface, not a clean solid.
Basically, joined surface would be fine, but as you see
3D Coat, the program I texture in, obviously has Normal
problems after import.

Hi Oliver - shell in MoI for thickening a surface can only really work on a single surface or one that is all smooth. Areas that have several surfaces meeting at an angle to on another are much more difficult because the offsets become separated and need to be extended out in order to meet up with each other.

If you make your object a closed solid rather than a joined surface by capping it off, shell might have a better chance, but what I'd probably do would be to manually make the inner core by doing a curve offset of the top and bottom pieces and then lofting between those, then do a boolean to cut it out, see attached model.

- Michael

Ty, Michael, that did the trick.