Hi Julian,

  The problem is that you create a large density map for your protein, but then Chimera doesn't display it at full resolution, because it is so large.  To make Chimera display the contour surface of the full resolution map set the "Step" value in the volume viewer dialog to 1, or use the equivalent command "volume #0 step 1" after the molmap command.

  Making the grid spacing 0.1 (40 times smaller than the resolution of 4 Angstroms) is likely to create a huge STL file that the printer will have trouble with, and it won't give any smoother appearance than say 0.4 I think.

Tom


On Nov 20, 2013, at 7:54 AM, Julian Gough  wrote:

Dear Tom,

I read what you wrote here:

http://plato.cgl.ucsf.edu/pipermail/chimera-users/2013-May/008825.html

I am really struggling to make an STL file for a coiled coil protein for 3D printing. What I see happening in Chimera does not seem to correspond to what you say, i.e. I use "molmap #0 4 grid 0.1" which according to you should be super-smooth -being far beyond what you suggest-, but the STL file that I export still has very large and obvious triangles.

I have played with it a great deal and I cannot find any way to control the number of triangles in the STL file. Whatever parameter I use for the grid, the output file is roughly similar in size. I can certainly fill the memory and crash it by making the grid smaller, but this is not reflected in the exported STL file.

ANy guidance much appreciated.

Julian


-- 
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Julian Gough
Professor of Bioinformatics
University of Bristol
Department of Computer Science
Merchant Venturers building
Woodland rd, Bristol, UK, BS8 1UB
Tel: +44 (0)117 3315221
Web: http://bioinformatics.bris.ac.uk
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