When building model airplanes, it is important to remove the seams and the joint lines. For most assemblies, crack and gaps become common through fitting. The most common issues pertain to the mating lines and wing roots of both sides of the aircraft's fuselage.
Materials you'll need for this project include different grades of sandpaper, a paint brush, sharp hobby knife, a container with some water and a paintbrush. You can also add the Tenax-7R and model putty.
If you'll be utilizing hazardous materials as you build model airplanes, make sure there's plenty of ventilation throughout your working space. Check the labels and warnings on the containers of these chemicals.