286 lines
11 KiB
OpenSCAD
286 lines
11 KiB
OpenSCAD
module threadPiece(Xa, Ya, Za, Xb, Yb, Zb, radiusa, radiusb, tipRatioa, tipRatiob, threadAngleTop, threadAngleBottom)
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{
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angleZ=atan2(Ya, Xa);
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twistZ=atan2(Yb, Xb)-atan2(Ya, Xa);
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polyPoints=[
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[Xa+ radiusa*cos(+angleZ), Ya+ radiusa*sin(+angleZ), Za ],
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[Xa+ radiusa*cos(+angleZ), Ya+ radiusa*sin(+angleZ), Za + radiusa*tipRatioa ],
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[Xa , Ya , Za+ radiusa*(tipRatioa+sin(threadAngleTop)) ],
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[Xa , Ya , Za ],
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[Xa , Ya , Za+ radiusa*sin(threadAngleBottom) ],
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[Xb+ radiusb*cos(angleZ+twistZ), Yb+ radiusb*sin(angleZ+twistZ), Zb ],
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[Xb+ radiusb*cos(angleZ+twistZ), Yb+ radiusb*sin(angleZ+twistZ), Zb+ radiusb*tipRatiob ],
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[Xb , Yb , Zb+ radiusb*(tipRatiob+sin(threadAngleTop)) ],
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[Xb , Yb , Zb ],
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[Xb , Yb , Zb+ radiusb*sin(threadAngleBottom)] ];
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polyTriangles=[
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[ 0, 1, 6 ], [ 0, 6, 5 ], // tip of profile
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[ 1, 7, 6 ], [ 1, 2, 7 ], // upper side of profile
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[ 0, 5, 4 ], [ 4, 5, 9 ], // lower side of profile
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[ 4, 9, 3 ], [ 9, 8, 3 ], [ 3, 8, 2 ], [ 8, 7, 2 ], // back of profile
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[ 0, 4, 3 ], [ 0, 3, 2 ], [ 0, 2, 1 ], // a side of profile
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[ 5, 8, 9 ], [ 5, 7, 8 ], [ 5, 6, 7 ] // b side of profile
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];
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polyhedron( polyPoints, polyTriangles );
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}
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module shaftPiece(Xa, Ya, Za, Xb, Yb, Zb, radiusa, radiusb, tipRatioa, tipRatiob, threadAngleTop, threadAngleBottom)
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{
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angleZ=atan2(Ya, Xa);
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twistZ=atan2(Yb, Xb)-atan2(Ya, Xa);
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threadAngleTop=15;
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threadAngleBottom=-15;
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shaftRatio=0.5;
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polyPoints1=[
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[Xa, Ya, Za + radiusa*sin(threadAngleBottom) ],
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[Xa, Ya, Za + radiusa*(tipRatioa+sin(threadAngleTop)) ],
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[Xa*shaftRatio, Ya*shaftRatio , Za + radiusa*(tipRatioa+sin(threadAngleTop)) ],
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[Xa*shaftRatio , Ya*shaftRatio , Za ],
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[Xa*shaftRatio , Ya*shaftRatio , Za + radiusa*sin(threadAngleBottom) ],
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[Xb, Yb, Zb + radiusb*sin(threadAngleBottom) ],
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[Xb, Yb, Zb + radiusb*(tipRatiob+sin(threadAngleTop)) ],
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[Xb*shaftRatio , Yb*shaftRatio , Zb + radiusb*(tipRatiob+sin(threadAngleTop)) ],
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[Xb*shaftRatio , Yb*shaftRatio , Zb ],
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[Xb*shaftRatio , Yb*shaftRatio , Zb + radiusb*sin(threadAngleBottom) ] ];
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polyTriangles1=[
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[ 0, 1, 6 ], [ 0, 6, 5 ], // tip of profile
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[ 1, 7, 6 ], [ 1, 2, 7 ], // upper side of profile
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[ 0, 5, 4 ], [ 4, 5, 9 ], // lower side of profile
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[ 3, 4, 9 ], [ 9, 8, 3 ], [ 2, 3, 8 ], [ 8, 7, 2 ], // back of profile
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[ 0, 4, 3 ], [ 0, 3, 2 ], [ 0, 2, 1 ], // a side of profile
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[ 5, 8, 9 ], [ 5, 7, 8 ], [ 5, 6, 7 ] // b side of profile
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];
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// this is the back of the raised part of the profile
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polyhedron( polyPoints1, polyTriangles1 );
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}
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module trapezoidThread(
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length=45, // axial length of the threaded rod
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pitch=10, // axial distance from crest to crest
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pitchRadius=10, // radial distance from center to mid-profile
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threadHeightToPitch=0.5, // ratio between the height of the profile and the pitch
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// std value for Acme or metric lead screw is 0.5
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profileRatio=0.5, // ratio between the lengths of the raised part of the profile and the pitch
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// std value for Acme or metric lead screw is 0.5
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threadAngle=30, // angle between the two faces of the thread
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// std value for Acme is 29 or for metric lead screw is 30
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RH=true, // true/false the thread winds clockwise looking along shaft, i.e.follows the Right Hand Rule
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clearance=0.1, // radial clearance, normalized to thread height
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backlash=0.1, // axial clearance, normalized to pitch
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stepsPerTurn=24 // number of slices to create per turn
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)
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{
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numberTurns=length/pitch;
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steps=stepsPerTurn*numberTurns;
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trapezoidRatio= 2*profileRatio*(1-backlash);
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function threadAngleTop(i)= threadAngle/2;
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function threadAngleBottom(i)= -threadAngle/2;
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function threadHeight(i)= pitch*threadHeightToPitch;
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function pitchRadius(i)= pitchRadius;
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function minorRadius(i)= pitchRadius(i)-0.5*threadHeight(i);
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function X(i)= minorRadius(i)*cos(i*360*numberTurns);
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function Y(i)= minorRadius(i)*sin(i*360*numberTurns);
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function Z(i)= pitch*numberTurns*i;
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function tip(i)= trapezoidRatio*(1-0.5*sin(threadAngleTop(i))+0.5*sin(threadAngleBottom(i)));
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// this is the threaded rod
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if (RH==true)
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translate([0,0,-threadHeight(0)*sin(threadAngleBottom(0))])
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for (i=[0:steps-1])
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{
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threadPiece(
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Xa= X(i/steps),
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Ya= Y(i/steps),
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Za= Z(i/steps),
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Xb= X((i+1)/steps),
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Yb= Y((i+1)/steps),
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Zb= Z((i+1)/steps),
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radiusa= threadHeight(i/steps),
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radiusb= threadHeight((i+1)/steps),
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tipRatioa= tip(i/steps),
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tipRatiob= tip((i+1)/steps),
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threadAngleTop= threadAngleTop(i),
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threadAngleBottom= threadAngleBottom(i)
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);
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shaftPiece(
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Xa= X(i/steps),
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Ya= Y(i/steps),
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Za= Z(i/steps),
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Xb= X((i+1)/steps),
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Yb= Y((i+1)/steps),
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Zb= Z((i+1)/steps),
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radiusa= threadHeight(i/steps),
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radiusb= threadHeight((i+1)/steps),
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tipRatioa= tip(i/steps),
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tipRatiob= tip((i+1)/steps),
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threadAngleTop= threadAngleTop(i),
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threadAngleBottom= threadAngleBottom(i)
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);
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}
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if (RH==false)
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translate([0,0,-threadHeight(0)*sin(threadAngleBottom(0))])
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mirror([0,1,0])
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for (i=[0:steps-1])
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{
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threadPiece(
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Xa= X(i/steps),
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Ya= Y(i/steps),
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Za= Z(i/steps),
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Xb= X((i+1)/steps),
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Yb= Y((i+1)/steps),
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Zb= Z((i+1)/steps),
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radiusa= threadHeight(i/steps),
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radiusb= threadHeight((i+1)/steps),
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tipRatioa= tip(i/steps),
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tipRatiob= tip((i+1)/steps),
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threadAngleTop= threadAngleTop(i),
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threadAngleBottom= threadAngleBottom(i)
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);
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shaftPiece(
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Xa= X(i/steps),
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Ya= Y(i/steps),
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Za= Z(i/steps),
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Xb= X((i+1)/steps),
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Yb= Y((i+1)/steps),
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Zb= Z((i+1)/steps),
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radiusa= threadHeight(i/steps),
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radiusb= threadHeight((i+1)/steps),
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tipRatioa= tip(i/steps),
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tipRatiob= tip((i+1)/steps),
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threadAngleTop= threadAngleTop(i),
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threadAngleBottom= threadAngleBottom(i)
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);
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}
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rotate([0,0,180/stepsPerTurn])
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cylinder(
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h=length+threadHeight(1)*(tip(1)+sin( threadAngleTop(1) )-1*sin( threadAngleBottom(1) ) ),
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r1=minorRadius(0)-clearance*threadHeight(0),
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r2=minorRadius(0)-clearance*threadHeight(0),
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$fn=stepsPerTurn
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);
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}
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module trapezoidThreadNegativeSpace(
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length=45, // axial length of the threaded rod
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pitch=10, // axial distance from crest to crest
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pitchRadius=10, // radial distance from center to mid-profile
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threadHeightToPitch=0.5, // ratio between the height of the profile and the pitch
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// std value for Acme or metric lead screw is 0.5
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profileRatio=0.5, // ratio between the lengths of the raised part of the profile and the pitch
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// std value for Acme or metric lead screw is 0.5
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threadAngle=30, // angle between the two faces of the thread
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// std value for Acme is 29 or for metric lead screw is 30
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RH=true, // true/false the thread winds clockwise looking along shaft, i.e.follows the Right Hand Rule
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countersunk=0, // depth of 45 degree chamfered entries, normalized to pitch
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clearance=0.1, // radial clearance, normalized to thread height
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backlash=0.1, // axial clearance, normalized to pitch
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stepsPerTurn=24 // number of slices to create per turn
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)
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{
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translate([0,0,-countersunk*pitch])
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cylinder(
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h=2*countersunk*pitch,
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r2=pitchRadius+clearance*pitch+0.25*pitch,
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r1=pitchRadius+clearance*pitch+0.25*pitch+2*countersunk*pitch,
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$fn=24
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);
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translate([0,0,countersunk*pitch])
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translate([0,0,-pitch])
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trapezoidThread(
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length=length+0.5*pitch, // axial length of the threaded rod
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pitch=pitch, // axial distance from crest to crest
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pitchRadius=pitchRadius+clearance*pitch, // radial distance from center to mid-profile
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threadHeightToPitch=threadHeightToPitch, // ratio between the height of the profile and the pitch
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// std value for Acme or metric lead screw is 0.5
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profileRatio=profileRatio, // ratio between the lengths of the raised part of the profile and the pitch
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// std value for Acme or metric lead screw is 0.5
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threadAngle=threadAngle, // angle between the two faces of the thread
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// std value for Acme is 29 or for metric lead screw is 30
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RH=true, // true/false the thread winds clockwise looking along shaft
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// i.e.follows Right Hand Rule
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clearance=0, // radial clearance, normalized to thread height
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backlash=-backlash, // axial clearance, normalized to pitch
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stepsPerTurn=stepsPerTurn // number of slices to create per turn
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);
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translate([0,0,length-countersunk*pitch])
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cylinder(
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h=2*countersunk*pitch,
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r1=pitchRadius+clearance*pitch+0.25*pitch,
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r2=pitchRadius+clearance*pitch+0.25*pitch+2*countersunk*pitch,$fn=24,
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$fn=24
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);
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}
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module trapezoidNut(
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length=45, // axial length of the threaded rod
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radius=25, // outer radius of the nut
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pitch=10, // axial distance from crest to crest
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pitchRadius=10, // radial distance from center to mid-profile
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threadHeightToPitch=0.5, // ratio between the height of the profile and the pitch
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// std value for Acme or metric lead screw is 0.5
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profileRatio=0.5, // ratio between the lengths of the raised part of the profile and the pitch
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// std value for Acme or metric lead screw is 0.5
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threadAngle=30, // angle between the two faces of the thread
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// std value for Acme is 29 or for metric lead screw is 30
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RH=true, // true/false the thread winds clockwise looking along shaft, i.e.follows the Right Hand Rule
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countersunk=0, // depth of 45 degree chamfered entries, normalized to pitch
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clearance=0.1, // radial clearance, normalized to thread height
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backlash=0.1, // axial clearance, normalized to pitch
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stepsPerTurn=24 // number of slices to create per turn
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)
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{
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difference()
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{
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cylinder(
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h=length,
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r1=radius,
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r2=radius,
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$fn=6
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);
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trapezoidThreadNegativeSpace(
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length=length, // axial length of the threaded rod
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pitch=pitch, // axial distance from crest to crest
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pitchRadius=pitchRadius, // radial distance from center to mid-profile
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threadHeightToPitch=threadHeightToPitch, // ratio between the height of the profile and the pitch
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// std value for Acme or metric lead screw is 0.5
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profileRatio=profileRatio, // ratio between the lengths of the raised part of the profile and the pitch
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// std value for Acme or metric lead screw is 0.5
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threadAngle=threadAngle, // angle between the two faces of the thread
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// std value for Acme is 29 or for metric lead screw is 30
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RH=true, // true/false the thread winds clockwise looking along shaft
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// i.e.follows Right Hand Rule
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countersunk=countersunk, // depth of 45 degree countersunk entries, normalized to pitch
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clearance=clearance, // radial clearance, normalized to thread height
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backlash=backlash, // axial clearance, normalized to pitch
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stepsPerTurn=stepsPerTurn // number of slices to create per turn
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);
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}
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} |