Here we see some alternate views and versions of the shape governed by:
One is rotating one way, and the same shape of opposite chirality is rotating the other way. I've chosen R/r =E (approximately) because it results in a 90degree overcrossing at the center, which I think looks cool and seems like a natural choice.
Here is a closer look at the last image:
r = 7.;
R = 19.;
plaht1[d_, rotation_] := ParametricPlot3D[{
u^Sin[r/R t] Sin[t + rotation],
u^Sin[r/R t] Cos[t + rotation],
Cos[r/R t] Log[u]
}, {t, 0, R* 2 Pi}, {u, 1 + d (E - 1)/20, 1 + (1 + d) (E - 1)/20},
PlotPoints -> {1000, 10}, PlotRange -> All, MaxRecursion -> 0,
PlotStyle -> {RGBColor[1, 0.75, 0.6], Thickness[0.04]},
Boxed -> False, Mesh -> False, Axes -> False]
plaht2[d_, rotation_] := ParametricPlot3D[{
u^Sin[r/R t] Sin[t - rotation],
u^Sin[r/R t] Cos[t - rotation],
-Cos[r/R t] Log[u]
}, {t, 0, R* 2 Pi}, {u, 1 + d (E - 1)/20, 1 + (1 + d) (E - 1)/20},
PlotPoints -> {1000, 10}, PlotRange -> All, MaxRecursion -> 0,
PlotStyle -> {RGBColor[0, 0.25, 0.4], Thickness[0.04]},
Boxed -> False, Mesh -> False, Axes -> False]
plaht3[rotation_, viewvector_] := ParametricPlot3D[{
u^Sin[r/R t] Sin[t - rotation],
u^Sin[r/R t] Cos[t - rotation],
-Cos[r/R t] Log[u]
}, {t, 0, R* 2 Pi}, {u, 1, E}, PlotPoints -> {1000, 10},
PlotRange -> All, MaxRecursion -> 0,
PlotStyle -> {RGBColor[0, 0.25, 0.4], Thickness[0.04]},
Boxed -> False, Mesh -> False, Axes -> False,
ViewVector -> viewvector]
plaht4[rotation_, viewvector_] := ParametricPlot3D[{
u^Sin[r/R t] Sin[t + rotation],
u^Sin[r/R t] Cos[t + rotation],
Cos[r/R t] Log[u]
}, {t, 0, R* 2 Pi}, {u, 1, E}, PlotPoints -> {1000, 10},
PlotRange -> All, MaxRecursion -> 0,
PlotStyle -> {RGBColor[1, 0.75, 0.6], Thickness[0.04]},
Boxed -> False, Mesh -> False, Axes -> False,
ViewVector -> viewvector]
plaht5[rotation_] := ParametricPlot3D[{
{u^Sin[r/R t] Sin[t + rotation],
u^Sin[r/R t] Cos[t + rotation],
Cos[r/R t] Log[u]},
{u^Sin[r/R t] Sin[t - rotation],
u^Sin[r/R t] Cos[t - rotation],
-Cos[r/R t] Log[u]}
}, {t, 0, R* 2 Pi}, {u, 1, E}, PlotPoints -> {1000, 10},
PlotRange -> All, MaxRecursion -> 0,
PlotStyle -> {{RGBColor[1, 0.75, 0.6],
Thickness[0.04]}, {RGBColor[0, 0.25, 0.4], Thickness[0.04]}},
Boxed -> False, Mesh -> False, Axes -> False]
plaht6[rotation_] := ParametricPlot3D[{
{u^Sin[r/R t] Sin[t + rotation],
u^Sin[r/R t] Cos[t + rotation],
Cos[r/R t] Log[u]},
{u^Sin[r/R t] Sin[t - rotation],
u^Sin[r/R t] Cos[t - rotation],
-Cos[r/R t] Log[u]}
}, {t, 0, R* 2 Pi}, {u, 1, E}, PlotPoints -> {1000, 10},
PlotRange -> {{-E, E}, {0, E}}, MaxRecursion -> 0,
PlotStyle -> {{RGBColor[1, 0.75, 0.6],
Thickness[0.04]}, {RGBColor[0, 0.25, 0.4], Thickness[0.04]}},
Background -> LightGray, Boxed -> False, Mesh -> False,
Axes -> False, ViewPoint -> Front]
Do[Export[StringJoin[ToString[rotation], ".png"],
GraphicsGrid[{
{plaht3[rotation, {5, -28, 5}], plaht4[rotation, {5, -28, 5}],
plaht5[rotation, {5, -28, 5}]}, {Show[plaht5[rotation],
ViewVector -> {50, -75, 150}],
Show[plaht5[rotation], ViewPoint -> Top], plaht6[rotation]},
{Show[plaht1[14, rotation ], plaht1[16, rotation ],
plaht1[18, rotation ], plaht2[15, rotation],
plaht2[17, rotation], plaht2[19, rotation],
ViewVertical -> {-20, 15, 10}],
Show[plaht1[14, rotation ], plaht1[16, rotation ],
plaht1[18, rotation ], plaht2[15, rotation],
plaht2[17, rotation], plaht2[19, rotation], ViewPoint -> Top],
Show[plaht1[14, rotation ], plaht1[16, rotation ],
plaht1[18, rotation ], plaht2[15, rotation],
plaht2[17, rotation], plaht2[19, rotation],
ViewPoint -> Front]}
}, ImageSize -> 800, Spacings -> 0]],
{rotation, 0, 6.2, 0.1}]