Urupema: covering wings with glass and building canopy frame

After giving the wings a final fit, filling some minor uneven surfaces on the lower side of the wing with polyester putty, the next step is covering the wings and elevator with 49gr glass fiber (lower side of the wings first). Before doing so we apply a watery primer (to avoid too much resin being absorbed by the abachi wood), which is slightly sanded and then the wing is wiped clean of all dust. The 49gr glass is applied with a roller and resin that has white colorant added as well as around 15% methanol (50gr resin, then add hardener etc. per wing). The methanol makes the resin very watery and easy to apply using the roller (and an old teflon frying pan).

I also finished the canopy frame and started builing the “lock”. The canopy frame looks quite good already, but will need a layer of filler before I can spray paint it. It was built by applying tape around the canopy base and two coats of liquid wax on the  areas where the canopy frame is lying on the fuselage. The frame is then built using first a bit of thickened epoxy (with micro-balloons and a bit of aerosil), then adding a bunch of carbon fibers. It is then further “filled out” with thickened epoxy. After giving it a rest of a few hours, allowing it to harden out a bit, I first rolled the upper side of the frame (after first applying cling film), to even out the top surface. I then filled any small uneven bits with thickened epoxy again and applied two layers of glass (280gr and then 160gr), and allowed it to harden out like that.

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