Abstract: A substantially all wood, lightweight, inexpensive tool that includes two elongate laterally adjustable base members that have longitudinal slots therein that are removably engageable by dowels to grip marginal edge portions of a sheet covering material therebetween. The span of covering material extending between the base members may be coverite, silk, monokote, solar film, silk span tissue, 3/4 inch fiberglass or the like. The tool when so containing the covering material is caused to overlie a wing or other desired portion of a model airplane that rests at a sufficient elevated position on a flat horizontal surface that the base members do not contact the latter; and the weight of the tool tensioning the span of covering material so that the latter extends over the leading and trailing edge of the wing. The span of covering material may be heat sealed or otherwise secured to the wing or model aircraft component.