Are you talking about building a sketch and model from a photo? If so, we have a basic tutorial on that here (Tutorial - Modeling an Exhaust Fairing):
http://eaa.org/swu
You may also be interested in following Eric Haddad's YouTube Channel for 3D-printed RD models:
https://www.youtube.com/channel/UCeo...kakABBJChjSn-A
Eric is one of our support volunteers that DS SolidWorks sponsors and they encouraged him to connect with us. Interestingly, he has modeled two 3D-printed RC aircraft that are based on unique aircraft from the EAA Museum (Phil Lockwood's AirCam that flew the Amazon for National Geographic, and Art Scholl's original Super Chipmunk).