# Combine multiple ParametricPlot3D to export to stl file (w/o using Show[])

I have multiple ParametricPlot3D functions, that I am visualizing together using the Show[] operator. However, I cannot export this as an stl file

Some of my functions:

helix2 = ParametricPlot3D[{Sin[t] , Cos[t], t + k*Pi}, {t, -10, 10}]
L1 = ParametricPlot3D[{-0.544021111 + 1.542611823 l, -0.839071529 +
0.892143075 l, 10 + 0 l}, {l, 0, 1}, PlotStyle -> {Yellow}]
L2 = ParametricPlot3D[{0.412118485 + 0.082764213 l, -0.911130262 +
1.780090051 l, 9 + 0 l}, {l, 0, 1}, PlotStyle -> {Orange}]

DNA = Show[helix1, helix2, L1, L2, L3, L4, L5, L6, L7, L8, L9, L10]


When I try to export to an stl file, this message pops up:

What can I do to put my graphic in a form so it will be able to export as an stl file??

• What are L3 through L10? Show should work. The fact that it remains blue suggests the graphic never got assigned to DNA. – b3m2a1 Dec 5 '17 at 17:00
• Also possibly relevant: it seems to me that .stl files can't take a curve like helix2 in the format, so you may want to consider converting it to a Tube or something. For example, if I try Export["helix.stl", helix2], I get "Export::nodta: STL contains no data that can be exported to the STL format.", but something like Export["helix.stl", helix2 /. Line[pts_] :> Tube[pts, .04]] works much better. – Anne Dec 5 '17 at 17:31
• Interesting, you're right, I tried exporting one helix alone, one line alone, and it still didn't work. And L3-L10 are just more lines, they're not really relevant to the issue I'm experiencing. Thank you for trying – Connor Dec 5 '17 at 19:12