CREATING SMALL FIBERGLASS PARTS

 

          Gathering all the thoughts I’ve heard on the subject, I set out to make some parts such as gear doors and cowl flaps for my Bonanza. I knew the first step was to have all the contours sanded smooth and shaped to the final shape I wanted.

 

          In the case of the nose gear doors, this meant the cowl was fitted and blended into the fuselage. The first step is to draw the desired final outline of the parts directly on the fuselage; be sure to have some alignment marks to assist you later in the process.

 

          Now we take some transparent MonoKote and iron it down over the area to be duplicated. Why? So we can see the lines drawn earlier after the resin and cloth parts have been made and then trace the marks of the outline directly on to the parts. Thanks to master scale builder Dave Platt for the idea of using the transparent parting material!

 

          For these parts, I use several layers of cloth starting with 6oz and ending with 3/4oz. We are looking for strength without excess weight. Use your old credit cards to really squeegee all the excess resin off the cloth just as described in the Fiberglass Finishing Techniques article.

 

          After curing, sand the newly created part smooth. This is the time to trace your lines and alignment marks. Now you can pop the parts off the MonoKote. Cut out the fuselage where necessary, then carefully cut and fit the ‘glass parts to fit. Be sure to allow some tolerance for shifting under air loads.  The photos show the doors being fitted and hinged using BVM Offset Hinges.  

         

          Another photo shows one of the ‘glass cowl flaps fitted; this slot is used to provide cooling air exhaust. In view are the exhaust extension and the Fuel Dot.