If you go up one level you will find a fine selection of custom connecting 
rods and side rods I've produced for Lego steam locomotives. These rods are 
available here: http://www.bricklink.com/store.asp?p=zephyr

Ronald 'Duq' Vallenduuk has developed a basic part design and subparts for 
LDraw based on these rods for his own use and he has graciously allowed me to 
share these files with you. I've merely expanded his template to use my own 
naming scheme and include many of the rod designs I've fabricated. Be sure to 
visit Duq's Flickr page or Bricklink store:

   http://www.flickr.com/photos/duq/
   http://www.bricklink.com/store.asp?p=Duq

For details on working with unofficial parts like this please visit 
http://LDraw.org but here's my quick description.

1) Find your ldraw directory

2) If you do not already have one, create a folder: Unofficial, and then a 
subfolder: parts, and finally a subsubfolder: s

   ".../ldraw/Unofficial/parts/s"

3) Download the .dat part files that you are interested in from this 
directory and store them in the parts folder from #2

4) Download ALL of the files from the s folder here and save them in the s 
folder from #2

5) Open your chosen LDraw software package and rescan your parts list (as per 
specific software directions)

6) Make beautiful virtual models


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Note, you may also need to install the latest LDraw parts update (2013-02 or newer), 
available from:

   http://LDraw.org
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