Stylized bolt

1 inch UNC dimensions
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ro=1./2​​ri=.8647/2​​p=1./8
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0.5
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0.43235
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0.125
Peak of threads
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ho=ParametricPlot3D[{roSin[t],-roCos[t],pt/(2Pi)},{t,0,16Pi},PlotStyle->{Black,AbsoluteThickness[3]},Axes->False]
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Valley of threads
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hi=ParametricPlot3D[{riSin[t+Pi],-riCos[t+Pi],pt/(2Pi)},{t,0,16Pi},PlotStyle->{Blue}]
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Shank
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c=Graphics3D[{AmbientLight[RGBColor[.9,.9,.9]],Opacity[.85],Cylinder[{{0,0,0},{0,0,8p}},ri]},Lighting->None]
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All together
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Show[c,ho,hi,ViewPoint->{8,4,2},ViewVertical->{.5,.25,1}]
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Side orthographic view
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Show[c,ho,hi,ViewPoint->{0,∞,0},ViewVertical->{1,0,0}]
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