Fin assembly 6

Traced the outline of the fin skeleton on the plywood blanks. The top line of the skins (specifically the forward part) is not well defined on the drawings, so I used the stabilizer airfoil to approximate the curve. Traced the outline of the stabilizer airfoil (nose part) with the axis of rotation marked, and made a paper template. Used the template to draw the top edge curve on the skins. Cut the two skins with a small overhang on fore/aft edges; the top/bottom edges were cut as close to final as possible, as trimming them later after gluing the skins will be difficult (top edge) or impossible (bottom edge).

Glued masking tape to the fore/aft edges of the right skin, then CA'ed spruce sticks to the masking tape (to be used for pressing down the skins). Mixed some laminating epoxy and added some red color pigment. Impressive, how only two drops is enough to add lots of color. The next step is sort of an experiment - I used laminating epoxy as the varnish, applied immediately before gluing the skins. Since this is the same epoxy that is used for the glue joints, and moreover, it is recommended to wet the plywood with pure epoxy before applying the bonding mixture, it should all work well. Applied the (varnish) epoxy with a short nap paint roller. Mixed some cotton-cab and glued the skin to the skeleton. Used spring clamps and woodworking bar clamps to press the edges of the skins to the fore/aft spars. The twist of the fin will need to be controlled carefully when the second skin is glued.