1. Entire framework is carefully shaped and sanded smooth, finishing with #400 sandpaper.
2. Framework gets a coat of clear dope at all points where it will touch the tissue, either Sig Lite Coat or nitrate.
3. Doped areas of framework are lightly sanded with 400 paper to remove "fuzz" raised by dope.
4. Another coat of dope is applied to the framework. Light sanding again if needed.
5. Oversize piece of tissue is placed over area of framework. Using a brush, acetone is applied to tissue where it
touches doped framework. The acetone instantly penetrates the tissue and causes the dope to become sticky, adhering the tissue to the framework. Work from rib to rib, upright to upright, etc., keeping the tissue snug as you go. Pull out wrinkles; re-apply acetone if needed to help. Work slowly and carefully. Be patient.
NOTE: Be sure the tissue grain runs spanwise on wings and tail pieces. This will prevent undue sagging between ribs. You can detrermine grain direction by tearing the tissue. If it tears straight and easy, that's the grain direction. If it tears with more difficulty and in a jagged fashion, you're going across the grain.
6. Shrink tissue with rubbing alcohol or water. If necessary, pin structure down to avoid warping as tissue shrinks.
7. Trim tissue using sharp razor blade, allowing a slight wrap-around at edges. Seal edges with clear dope. Give
finishing piece two coats of clear dope thinned 50/50 to seal and protect it. Do not use butyrate clear dope, as it
shrinks badly and will cause serious warps! Sig Lite Coat is butyrate, but with plasticizer added to prevent shrinkage. Aero Dyne in CA sells non-shrink nitrate dope, which I think works as well: www.freeflightmodels.com
For very light wing and tail structure, I pre-shrink the tissue by laying the pieces on a framed window screen and
spraying them with water. When dry, they are wrinkled and I iron them flat with a medium iron. The tissue will still
have a texture to it, but that won't effect flying qualities. Apply as above.
Those wheel pants can be covered by using wet tissue. Using a shallow pan of water, submerge the piece of tissue, then blot it with a paper towel. Apply as above. You'll find, with some practice, that wet tissue will conform to curved surfaces much, much better than when it's dry. You should be able to cover the pants with two pieces.
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