Import Stl files (again, but different) and BOSL2

Hello everyone,

first let me introduce myself.
I am Henk, 57 years young.
I am building a boat, 6 meter long and designing it completely in openscad.
When finished, I use a CNC machine to cut out the parts.
First scale 1:10 (on a 3018 cnc machine), later real size. (on a maslov cnc
machine)

Now the thing.
Because I have a lot of parts, all with a lot of calculations, it slows down
my machine.
My solution seemed simple: export finished parts as STL, then replace the
code with the imported STL.
And it worked, partially, a bit, a little bit.
The imported parts couldn’t import or didn’t show when renderd.
On this forum I found the “perfect” stl problem, so I fixed the stl files
with polyfix (nice), freescad and blender.
And then the weird stuff started.
All of the Stl files imported fine, they all rendered fine.
But when I imported more than 1 stl and tried to render them, none showed
up.
So I created a program with just 4 import commands and activated them one by
one.
And I got strange outcomings.
1 – worked
1-2 worked
1-2-3 1 disappeared, 2 and 3  visible
1-2-4 all disappeared,
3 – worked
1-4 4 disappeared, 1 visible
Then with a second try, all outcomings changed.
Also when a stl disappears, it stay away and I have to restart openscad to
make it visible again.
In the preview it works fine.
I got 32Gb, I7, gtx 1650S, win 10, so a heavy machine.
Anyone a clue what’s wrong?

Also,
Has anyone experience with the BOSL2 library?, is it stable with openscad?

Rgrds
Henk





--
Sent from: http://forum.openscad.org/

_______________________________________________
OpenSCAD mailing list
[hidden email]
http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org

On 14.05.20 12:58, Kevig wrote:
> I am building a boat, 6 meter long and designing it completely
> in openscad. When finished, I use a CNC machine to cut out the
> parts. First scale 1:10 (on a 3018 cnc machine), later real
> size. (on a maslov cnc machine)

Uff, wow, nice! Please post pictures :-).

> My solution seemed simple: export finished parts as STL, then
> replace the code with the imported STL.

STL is especially bad for that due to how the file format is
structured. I would have immediately suggested using 3MF but
there's a bug in the release version (just fixed last week)
that can cause cavities to disappear. So you could give it a
try if none of the parts has internal cavities (which I assume
might be the case if it's for a CNC?).

There is currently a project started that covers on-disk
caching. I suppose that would be the best solution. So
crossing fingers that goes as planned.
(That's the "Help me in choosing the perfect key-value
datastore for persistent cache (GSOC 2020)" forum thread)

> Also when a stl disappears, it stay away and I have to
> restart openscad to make it visible again.

This sounds like an old bug that should not happen anymore
with the latest release. Which OpenSCAD version is it?

ciao,
  Torsten.

_______________________________________________
OpenSCAD mailing list
[hidden email]
http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org

@Torsten.
I am using 2019-5. (tried 2020-4, but it crashed).

I will try the 3mf suggestion, and you are right, no cavities in my design.

also a picture of my boat, without hull.
<http://forum.openscad.org/file/t2834/sparky.jpg>

and the goal(not exactly, somewhat like this)
<http://forum.openscad.org/file/t2834/Gerestaureerde-loodsjol.jpg>

rgrds
Henk



--
Sent from: http://forum.openscad.org/

_______________________________________________
OpenSCAD mailing list
[hidden email]
http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org

_______________________________________________
OpenSCAD mailing list
[hidden email]
http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org

The BOSL2 library is NOT stable.  It is still very dynamic, under rapid
development.  It is also supported and in its current stage you have the
opportunity to try things out and recommend radical (e.g. non backwards
compatible) changes before things settle down.  



--
Sent from: http://forum.openscad.org/

_______________________________________________
OpenSCAD mailing list
[hidden email]
http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org

On 2020-05-14 12:58, Kevig wrote:
Hello Henk,

Did you render with F6 in OpenSCAD?

An alternative to importing STL is to store the parts as 2D DXF or SVG
and import them as such + immediately use linear_extrude to the required
thickness. That is assuming all your parts are flat. Not sure if it
solves the problem, but maybe. At least it is necessary to find the
cause of the problem you are seeing, or else it might happen again.

Carsten Arnholm

_______________________________________________
OpenSCAD mailing list
[hidden email]
http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org

@nophead and Carsten

yes i did render with F6
I did use the possibility of SVG and extract to get the rib's and keel from
the drawing to a 3d model.
Unfortunally almost every part has angled, curved or round sides (see
picture)
(A future problem wil be to find a free slicer program, capable of creating
grbl g-code for these sides.)
<http://forum.openscad.org/file/t2834/spant-10.jpg>

@adrianv

thanks,
Then this library is not for me.
If i change just one part of the boat, everything has to be recalculated.
A missing or failing command will crash the boat and possible openscad, not
to mention the efford to repair the danage.

@all
As soon as i have results from the 3MF option, i let you know

rgrds
Henk



--
Sent from: http://forum.openscad.org/

_______________________________________________
OpenSCAD mailing list
[hidden email]
http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org

hello,

As promised the results of the 3MF experiment.
short version - no difference, same behavier

long version
i used 2 rib's of the boat Rib2 and rib3.
both renderd fine (F6) and imported fine.(no errors or warnings)
but when imported together and renderd none showed up.
when only one of both where imported and renderd with the rest of the boat
it didn't show up but the rest of the boat did.
when both where imported and renderd with the rest of the boat nothing
showed up.
when both are stored as one file (renderd together and exported as 1 3MF
file) it went fine.
When this (double) file was imported and renderd with the rest of the boat
nothing showed up
so??????????

tomorrow i am going to try it with 2 simple objects (2 cubes) and see what
happens

rgrds
Henk



--
Sent from: http://forum.openscad.org/

_______________________________________________
OpenSCAD mailing list
[hidden email]
http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org

On 16.05.20 17:52, Kevig wrote:
> i used 2 rib's of the boat Rib2 and rib3.
> both renderd fine (F6) and imported fine.(no errors or warnings)

Is it possible to share those 2 files?

ciao,
  Torsten.


_______________________________________________
OpenSCAD mailing list
[hidden email]
http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org

of course Torsten.

Boot_Spant_2.3mf <http://forum.openscad.org/file/t2834/Boot_Spant_2.3mf>  
Boot_Spant_3.3mf <http://forum.openscad.org/file/t2834/Boot_Spant_3.3mf>  
Boot_Spant_23.3mf <http://forum.openscad.org/file/t2834/Boot_Spant_23.3mf>  

rgrds
Henk



--
Sent from: http://forum.openscad.org/

_______________________________________________
OpenSCAD mailing list
[hidden email]
http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org

OpenSCAD version 2019.05

When I import any one of:
Boot_Spant_2.3mf    previews   renders
Boot_Spant_3.3mf    previews   renders
Boot_Spant_23.3mf   previews   renders

all three together
   Boot_Spant_2.3mf    previews only
   Boot_Spant_3.3mf    previews only
   Boot_Spant_23.3mf   previews only

two together
   Boot_Spant_2.3mf    previews only
   Boot_Spant_3.3mf    previews only

   Boot_Spant_2.3mf    previews  
   Boot_Spant_23.3mf   previews CGAL error

   Boot_Spant_3.3mf    previews
   Boot_Spant_23.3mf   previews CGAL error

ERROR: CGAL error in CGAL_Nef_polyhedron3(): CGAL ERROR: assertion
violation! Expr: e_below != SHalfedge_handle() File:
/mxe/usr/x86_64-w64-mingw32.static.posix/include/CGAL/Nef_3/SNC_FM_decorator.h
Line: 426






--
Sent from: http://forum.openscad.org/

_______________________________________________
OpenSCAD mailing list
[hidden email]
http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org

@lar3ry
you are right about the CGAL error.

I did try with some simple objects and it worked fine.

I also found out there is some construction fault in the exported files,
which is no problem for most program's, but is for CGAL
so i now suspect it had something to do with the way i constucted the spant.

i am now in painstaking the process of creating stl/off/3mf files of every
construction step and checking wich construction step causes the error.

i will keep you informed

rgrds
Henk



--
Sent from: http://forum.openscad.org/

_______________________________________________
OpenSCAD mailing list
[hidden email]
http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org