Hi I'm new here and just discovered openscad. I work for a filament producer and have therefor much to do with 3d printing and CAD, but no idea of programming in general. I'm working on a similar Problem: I solved this by creating the same object again minus the wall thikness: x=1; // Wall thickness difference(){ cube([50,50,100], center=true); cube([50-x,50-x,101], center=true); } But this way one has to create the same object twice and keep track of the walls, were it needs to be substracted and were not. It is easy to get lost between them both. I'm hoping to find a solution, were I generate the part twice with a different x-value and make a difference out of both. The best I could come up with was like: x=1; // wall thickness for (i=[0:1]) difference(){ x=i; cube([50-x,50-x,100], center=true); } but it doesn't work like this. any suggestions? thanks in advance -- View this message in context: http://forum.openscad.org/make-an-object-hollow-with-constant-wall-thickness-tp14255p14475.html Sent from the OpenSCAD mailing list archive at Nabble.com.

for does an implicit union betweeen its children. And the syntax for difference() is always A-B1-B2-B3.... a=50; b=100; x=1; // small number e=0.01; module tube(a,b,x){ difference(){ cube([a,a,b]); translate([x,x,-e])cube([a-2*x,a-2*x,b+2*e]); } } tube(a,b,x); 2015-11-14 17:26 GMT+01:00 plasticmonk <deurer@rocketmail.com>: > Hi I'm new here and just discovered openscad. I work for a filament > producer > and have therefor much to do with 3d printing and CAD, but no idea of > programming in general. > > I'm working on a similar Problem: I solved this by creating the same object > again minus the wall thikness: > > > x=1; // Wall thickness > > difference(){ > cube([50,50,100], center=true); > cube([50-x,50-x,101], center=true); > } > > > But this way one has to create the same object twice and keep track of the > walls, were it needs to be substracted and were not. It is easy to get lost > between them both. > > I'm hoping to find a solution, were I generate the part twice with a > different x-value and make a difference out of both. > > The best I could come up with was like: > > > x=1; // wall thickness > > for (i=[0:1]) > difference(){ > x=i; > cube([50-x,50-x,100], center=true); > } > > > but it doesn't work like this. any suggestions? > thanks in advance > > > > > > > > > -- > View this message in context: > http://forum.openscad.org/make-an-object-hollow-with-constant-wall-thickness-tp14255p14475.html > Sent from the OpenSCAD mailing list archive at Nabble.com. > > _______________________________________________ > OpenSCAD mailing list > Discuss@lists.openscad.org > http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >

Another way to go is to to the wlls in 2d and extrude them: a=50; b=100; x=1; // small number e=0.01; module tube(a,b,x){ linear_extrude(h=b){ difference(){ square([a,a]); translate([x,x])square([a-2*x,a-2*x]); } } } tube(a,b,x); 2015-11-14 21:07 GMT+01:00 Peter Falke <stempeldergeschichte@googlemail.com> : > for does an implicit union betweeen its children. > And the syntax for difference() is always A-B1-B2-B3.... > > a=50; > b=100; > > x=1; > > // small number > e=0.01; > > module tube(a,b,x){ > difference(){ > cube([a,a,b]); > translate([x,x,-e])cube([a-2*x,a-2*x,b+2*e]); > } > } > > tube(a,b,x); > > 2015-11-14 17:26 GMT+01:00 plasticmonk <deurer@rocketmail.com>: > >> Hi I'm new here and just discovered openscad. I work for a filament >> producer >> and have therefor much to do with 3d printing and CAD, but no idea of >> programming in general. >> >> I'm working on a similar Problem: I solved this by creating the same >> object >> again minus the wall thikness: >> >> >> x=1; // Wall thickness >> >> difference(){ >> cube([50,50,100], center=true); >> cube([50-x,50-x,101], center=true); >> } >> >> >> But this way one has to create the same object twice and keep track of the >> walls, were it needs to be substracted and were not. It is easy to get >> lost >> between them both. >> >> I'm hoping to find a solution, were I generate the part twice with a >> different x-value and make a difference out of both. >> >> The best I could come up with was like: >> >> >> x=1; // wall thickness >> >> for (i=[0:1]) >> difference(){ >> x=i; >> cube([50-x,50-x,100], center=true); >> } >> >> >> but it doesn't work like this. any suggestions? >> thanks in advance >> >> >> >> >> >> >> >> >> -- >> View this message in context: >> http://forum.openscad.org/make-an-object-hollow-with-constant-wall-thickness-tp14255p14475.html >> Sent from the OpenSCAD mailing list archive at Nabble.com. >> >> _______________________________________________ >> OpenSCAD mailing list >> Discuss@lists.openscad.org >> http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >> > >