John,
I sent you mail on this, but here it is so others can see it:
————————————————————-
<<Utilitie`DXF`
<<Graphics`Graphics3D`
bx = 6 Cos[u] (1 + Sin[u]);
by = 16 Sin[u];
rad = 4 ( 1 – Cos[u] / 2);
X = If[Pi < u <= 2 Pi, bx + rad Cos[v + Pi],
bx + rad Cos[u] Cos[v]];
Y = If[Pi < u <= 2 Pi, by, by + rad Sin[u] Cos[v]];
Z = rad Sin[v];
klein = ParametricPlot3D[{X, Y, Z}, {u, 0, 2 Pi}, {v, 0, 2 Pi},
PlotPoints -> {48,12}, Axes -> False,
Boxed -> False, ViewPoint -> {1.4, -2.6, -1.7}]
WriteDXF["klein.dxf", klein]