I have a problem. I'm used to CSG in povray where I can use a clipping plane to throw away anything on one side of the plane. I could cut a cylinder on a diagonal by using a rotated plane centered at the appropriate point. I am not seeing a similar functionality here. I want a slice of a cylinder. When I use a cube, the cube has size which throws everything off. Inch = 25.4 ; // define inches MC_ID = 46 ; Thick = 2 ; // MC_Len = (2 * Inch); MC_OD = (MC_ID + (Thick*2)); module MainCyl () { cylinder(h = MC_Len, r=(MC_OD/2), center = true, $fn=200); } // End of MainCyl module MC_Inside () { cylinder(h = (MC_Len+1), r=(MC_ID/2), center = true, $fn=200); } module Clip(){ cube ( size = [(MC_OD+1),(MC_OD+1),100],center = true); } difference (){ MainCyl(); MC_Inside(); translate ([0,0,30]){ rotate ([0,45,0]) { Clip(); } // End of rotate } // end of translate } -- View this message in context: http://forum.openscad.org/Clipping-a-cylinder-tp13578.html Sent from the OpenSCAD mailing list archive at Nabble.com.

Would this be what you are wanting? I modified two lines, the translation and the Z size of the cube Inch = 25.4 ; // define inches MC_ID = 46 ; Thick = 2 ; // MC_Len = (2 * Inch); MC_OD = (MC_ID + (Thick*2)); module MainCyl () { cylinder(h = MC_Len, r=(MC_OD/2), center = true, $fn=200); } // End of MainCyl module MC_Inside () { cylinder(h = (MC_Len+1), r=(MC_ID/2), center = true, $fn=200); } module Clip(){ cube ( size = [(MC_OD+1),(MC_OD+1),200],center = true); } difference (){ MainCyl(); MC_Inside(); translate ([0,0,sqrt(2)/2*MC_OD]){ rotate ([0,45,0]) { Clip(); } // End of rotate } // end of translate } -- don bright hmbright@fastmail.fm On Fri, Aug 21, 2015, at 04:06 PM, dbvanhorn wrote: > > I have a problem. I'm used to CSG in povray where I can use a clipping > plane to throw away anything on one side of the plane. I could cut a > cylinder on a diagonal by using a rotated plane centered at the > appropriate > point. > > I am not seeing a similar functionality here. I want a slice of a > cylinder. > When I use a cube, the cube has size which throws everything off. > > Inch = 25.4 ; // define inches > > MC_ID = 46 ; > Thick = 2 ; // > MC_Len = (2 * Inch); > > MC_OD = (MC_ID + (Thick*2)); > > module MainCyl () { > cylinder(h = MC_Len, r=(MC_OD/2), center = true, $fn=200); > } // End of MainCyl > > module MC_Inside () { > cylinder(h = (MC_Len+1), r=(MC_ID/2), center = true, $fn=200); > } > > module Clip(){ > cube ( size = [(MC_OD+1),(MC_OD+1),100],center = true); > } > > difference (){ > MainCyl(); > MC_Inside(); > translate ([0,0,30]){ > rotate ([0,45,0]) { > Clip(); > } // End of rotate > } // end of translate > } > > > > -- > View this message in context: > http://forum.openscad.org/Clipping-a-cylinder-tp13578.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

That gives the right shape, thank you! But it doesn't scale. I know OpenSCAD doesn't have clipping planes, I'm looking for a replacement, even if it takes the form of a module that I could use as a clipping plane. Sizeless objects are powerful. On Fri, Aug 21, 2015 at 3:28 PM, don bright <hmbright@fastmail.fm> wrote: > Would this be what you are wanting? I modified two lines, the > translation and the Z size of the cube > > Inch = 25.4 ; // define inches > > MC_ID = 46 ; > Thick = 2 ; // > MC_Len = (2 * Inch); > > MC_OD = (MC_ID + (Thick*2)); > > module MainCyl () { > cylinder(h = MC_Len, r=(MC_OD/2), center = true, $fn=200); > } // End of MainCyl > > module MC_Inside () { > cylinder(h = (MC_Len+1), r=(MC_ID/2), center = true, $fn=200); > } > > module Clip(){ > cube ( size = [(MC_OD+1),(MC_OD+1),200],center = true); > } > > difference (){ > MainCyl(); > MC_Inside(); > translate ([0,0,sqrt(2)/2*MC_OD]){ > rotate ([0,45,0]) { > Clip(); > } // End of rotate > } // end of translate > } > > > -- > don bright > hmbright@fastmail.fm > > On Fri, Aug 21, 2015, at 04:06 PM, dbvanhorn wrote: > > > > I have a problem. I'm used to CSG in povray where I can use a clipping > > plane to throw away anything on one side of the plane. I could cut a > > cylinder on a diagonal by using a rotated plane centered at the > > appropriate > > point. > > > > I am not seeing a similar functionality here. I want a slice of a > > cylinder. > > When I use a cube, the cube has size which throws everything off. > > > > Inch = 25.4 ; // define inches > > > > MC_ID = 46 ; > > Thick = 2 ; // > > MC_Len = (2 * Inch); > > > > MC_OD = (MC_ID + (Thick*2)); > > > > module MainCyl () { > > cylinder(h = MC_Len, r=(MC_OD/2), center = true, $fn=200); > > } // End of MainCyl > > > > module MC_Inside () { > > cylinder(h = (MC_Len+1), r=(MC_ID/2), center = true, $fn=200); > > } > > > > module Clip(){ > > cube ( size = [(MC_OD+1),(MC_OD+1),100],center = true); > > } > > > > difference (){ > > MainCyl(); > > MC_Inside(); > > translate ([0,0,30]){ > > rotate ([0,45,0]) { > > Clip(); > > } // End of rotate > > } // end of translate > > } > > > > > > > > -- > > View this message in context: > > http://forum.openscad.org/Clipping-a-cylinder-tp13578.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 > > _______________________________________________ > OpenSCAD mailing list > Discuss@lists.openscad.org > http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org > -- K1FZY (WA4TPW) SK 9/29/37-4/13/15

I added a # to your clip module to see the cube. <http://forum.openscad.org/file/n13581/OpenSCAD_clip_001030.png> It shows that perhaps you need to resize the cube so it clips the entire cylinder. I find making the cube a large margin bigger than the diameter of the cylinder is easiest to ensure you cut all the way through. <http://forum.openscad.org/file/n13581/OpenSCAD_clip_001032.png> However you could just multiply the cyl size by cos/sin of suitable angles and add Delta to ensure the cube is of a suitable dimension and is only slightly larger than required. module Clip(){ #cube ( size = [(MC_OD+1),(MC_OD+1),120],center = true); } see this one: http://www.thingiverse.com/thing:942124 Open it in customizer and see visualisation clip. Look in code for sin/cos associated with positioning the internal filament cut hole. -- View this message in context: http://forum.openscad.org/Clipping-a-cylinder-tp13578p13581.html Sent from the OpenSCAD mailing list archive at Nabble.com.

Your question is unclear. Does "I want to slice a cylinder" mean 1. "I want to cut a slice off a cylinder", or 2. "I want to cut a slice out of a cylinder", or . . . Be that as it may, you are probably not aware that you can make shapes transparent. In the code, I have disabled difference() and made Clip() transparent. This way, you can see what you are doing and decide for yourself how to adapt the code to your needs. Inch = 25.4 ; // define inches MC_ID = 46 ; Thick = 2 ; // MC_Len = (2 * Inch); MC_OD = (MC_ID + (Thick*2)); module MainCyl () { cylinder(h = MC_Len, r=(MC_OD/2), center = true, $fn=200); } // End of MainCyl module MC_Inside () { cylinder(h = (MC_Len+1), r=(MC_ID/2), center = true, $fn=200); } module Clip(){ cube ( size = [(MC_OD+1),(MC_OD+1),100],center = true); } //difference (){ MainCyl(); MC_Inside(); translate ([0,0,30]){ rotate ([0,45,0]) { # Clip(); } // End of rotate } // end of translate //} -- View this message in context: http://forum.openscad.org/Clipping-a-cylinder-tp13578p13583.html Sent from the OpenSCAD mailing list archive at Nabble.com.

Try the script below and change from union() to intersection() to difference() to see what you want Good luck and fun with OpenSCAD Jean-Paul AC9GH Inch = 25.4 ; // define inches MC_ID = 46; Thick = 2; MC_Len = 3 * Inch; Angle = 45; Height = 19; MC_OD = MC_ID + 2 * Thick; module MainTube() { difference() { cylinder(h = MC_Len, r=(MC_OD/2), center = true, $fn=200); cylinder(h = (MC_Len+1), r=(MC_ID/2), center = true, $fn=200); } // End of difference() } // End of MainTube module Clip(){ cube ([2*MC_OD,2*MC_OD,Height],center = true); } //union() { intersection() { //difference() { MainTube(); rotate ([0,Angle,0]) Clip(); } > On Aug 21, 2015, at 6:02 PM, wolf <wv99999@gmail.com> wrote: > > Your question is unclear. Does "I want to slice a cylinder" mean > 1. "I want to cut a slice off a cylinder", or > 2. "I want to cut a slice out of a cylinder", or . . . > > Be that as it may, you are probably not aware that you can make shapes > transparent. In the code, I have disabled difference() and made Clip() > transparent. This way, you can see what you are doing and decide for > yourself how to adapt the code to your needs. > > Inch = 25.4 ; // define inches > > MC_ID = 46 ; > Thick = 2 ; // > MC_Len = (2 * Inch); > > MC_OD = (MC_ID + (Thick*2)); > > module MainCyl () { > cylinder(h = MC_Len, r=(MC_OD/2), center = true, $fn=200); > } // End of MainCyl > > module MC_Inside () { > cylinder(h = (MC_Len+1), r=(MC_ID/2), center = true, $fn=200); > } > > module Clip(){ > cube ( size = [(MC_OD+1),(MC_OD+1),100],center = true); > } > > //difference (){ > MainCyl(); > MC_Inside(); > translate ([0,0,30]){ > rotate ([0,45,0]) { > # Clip(); > } // End of rotate > } // end of translate > //} > > > > > > -- > View this message in context: http://forum.openscad.org/Clipping-a-cylinder-tp13578p13583.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

Hi David, Below is a gist link to an OpenSCAD module that will fake a clipping plane using the cube object. It is based on POV-ray syntax. For example: difference() { sphere(3); fakeclipplane([1,1,2],2,10); } This will 'clip' a sphere of radius 3 using a plane with normal vector 1,1,2 at distance '2' from origin, using a 'cube' of size 10 to fake the plane https://gist.github.com/donbright/0ba2934c6c9b7b69c411 Please let me know if it is what you were looking for. --   don bright   http://github.com/donbright   hmbright@fastmail.fm On Fri, Aug 21, 2015, at 04:32 PM, david vanhorn wrote: > > That gives the right shape, thank you!   But it doesn't scale.  > > I know OpenSCAD doesn't have clipping planes, I'm looking for a replacement, even if it takes the form of a module that I could use as a clipping plane. > Sizeless objects are powerful. > > On Fri, Aug 21, 2015 at 3:28 PM, don bright <hmbright@fastmail.fm> wrote: >> Would this be what you are wanting? I modified two lines, the >> translation and the Z size of the cube >> >> Inch = 25.4 ; // define inches >> >> MC_ID = 46 ; >> Thick = 2   ; // >> MC_Len = (2 * Inch); >> >> MC_OD = (MC_ID + (Thick*2)); >> >> module MainCyl () { >>     cylinder(h = MC_Len, r=(MC_OD/2), center = true, $fn=200); >> } // End of MainCyl >> >> module MC_Inside () { >>     cylinder(h = (MC_Len+1), r=(MC_ID/2), center = true, $fn=200); >> } >> >> module Clip(){ >>      cube ( size = [(MC_OD+1),(MC_OD+1),200],center = true); >> } >> >> difference (){ >>     MainCyl(); >>     MC_Inside(); >>     translate ([0,0,sqrt(2)/2*MC_OD]){ >>         rotate ([0,45,0]) { >>             Clip(); >>         } // End of rotate >>     } // end of translate >> } >> >> >> -- >>   don bright >> hmbright@fastmail.fm >> >> On Fri, Aug 21, 2015, at 04:06 PM, dbvanhorn wrote: >> > >> > I have a problem.   I'm used to CSG in povray where I can use a clipping >> > plane to throw away anything on one side of the plane.  I could cut a >> > cylinder on a diagonal by using a rotated plane centered at the >> > appropriate >> > point. >> > >> > I am not seeing a similar functionality here.  I want a slice of a >> > cylinder. >> > When I use a cube, the cube has size which throws everything off. >> > >> > Inch = 25.4 ; // define inches >> > >> > MC_ID = 46 ; >> > Thick = 2   ; // >> > MC_Len = (2 * Inch); >> > >> > MC_OD = (MC_ID + (Thick*2)); >> > >> > module MainCyl () { >> >     cylinder(h = MC_Len, r=(MC_OD/2), center = true, $fn=200); >> > } // End of MainCyl >> > >> > module MC_Inside () { >> >     cylinder(h = (MC_Len+1), r=(MC_ID/2), center = true, $fn=200); >> > } >> > >> > module Clip(){ >> >      cube ( size = [(MC_OD+1),(MC_OD+1),100],center = true); >> > } >> > >> > difference (){ >> >     MainCyl(); >> >     MC_Inside(); >> >     translate ([0,0,30]){ >> >         rotate ([0,45,0]) { >> >             Clip(); >> >         } // End of rotate >> >     } // end of translate >> > } >> > >> > >> > >> > -- >> > View this message in context: >> > http://forum.openscad.org/Clipping-a-cylinder-tp13578.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 >> >> _______________________________________________ >> OpenSCAD mailing list >> Discuss@lists.openscad.org >> http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org > > > > -- > K1FZY (WA4TPW) SK  9/29/37-4/13/15 > _________________________________________________ > OpenSCAD mailing list > Discuss@lists.openscad.org > http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org