An infrared thermometer with laser pointer (above) allows accurate temperature control for covering purposes. Weldwood contact cement (below) by DAP Industries provides excellent adhesion of “Ceconite” while providing low VOC's and water cleanup.
I like a waterborne contact cement such as Weldwoods’ Nonflammable because of its water cleanup capability and low volatile or- ganic compounds (VOC). For this application we are going to ad-
here the fabric to the frame with waterborne contact cement thinned 10% with distilled water. Twenty or thirty cc’s is usually enough cement to do several large wing pan- els. A small foam brush works well for ap- plication. Note that although this is “contact cement” we’re setting the fabric in place with the cement “wet”. The wing in this il- lustration is elliptical and a bit more chal- lenging than a rectangular wing. I cut the fabric into four pieces for the top
and bottom and left and right wing panels. Starting with a top wing panel, apply cement to the leading and trailing edges, the wing tip and inboard wing panel. Position the fab- ric so there is approximately ½ to ¾ inch ex- tending past the trailing edge. Work the fab-
FLYING MODELS
ric into the cement around the periphery of the airframe pulling it tight and working out the wrinkles as much as possible. This wing has only a leading edge stringer for attachment of the fabric so care must be taken to ensure total adhesion pri- or to the heat shrink process. With a sharp pair of scissors or razor blade, trim the fab- ric smoothly to the contour of the leading edge stringer. Now apply cement to the bot- tom of the trailing edge and wrap the fabric around the back of the trailing edge secur- ing it to the bottom panel. Trim the wing tip fabric to its contour leaving a slight over- hang. Cut slits in the fabric to the edge of the wing tip at the points of greatest curva- ture. Apply contact cement to the edge of the wing tip and work the fabric around the curvature. With the preheated iron work the fabric further into the curve. The fabric will shrink, forming to the contour of the wing
tip. Now seal the entire glued periphery us- ing the iron to work out any wrinkles in the fabric being glued. Do not shrink open bays yet! This process helps to cure the cement and firmly attach the fabric to the frame. Repeat the cement application to the pe- ripheral structure on the top of the wing. Apply the fabric as before, pulling it as tight as possible while working it into the cement. Trim the leading edge so the fabric follows the contour of the leading edge. This fabric edge will be visible so care should be taken to trim a smooth contour. Next trim the fab- ric flush to the trailing edge and finish the wing tip as before. Check to make sure the fabric is sealed all around the airframe. If any areas are not sealed, a little cement on the surface can be worked in through the weave and sealed with the iron. Any wrinkles remaining can be worked out during the heat shrink process. Note that for rectangular wings it
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