Well it has just gone 11:45pm and the current temperature is 82F. Ok, I am in Australia. And I think we hit 100F earlier today. Anyway, I had planned to finish the carbon fiber layer on the underside of the wing today but realized it would be an impossible task in this heat. I did about 1/3 of the wing last night when the air temperature was 66F and found that even with the slow acting hardener and my one pair of hands, the resin was curing faster than I would have liked. I was busier than a one armed brick layer in Beruit.(Australian saying). Today was a definite no no for large scale resin work. I did some work on a bellcrank, cut some more carbon fiber for the wing.........while I am on the subject, cutting all this fabric on the 45 degree bias has left me with heaps of offcut wedges. Think I will have enough to build a delta wing after the KR! I also cleaned up the garage and before throwing out some scrap CF and FG pieces I decided to heat test light and dark colors with a small temperature gun.
I had 3 pieces of cured composite. The first piece of carbon fiber had been peeled off some composite work, so it had the dark micro stuck to the underside. The second piece was the aileron trailing edge offcut so it had 1/8" flox between 2 layers of carbon fiber. The third piece was a single layer of fiber glass. I used a pressure pack can of gloss white paint on the end of each as can been seen in this photo http://www.kr-2s.com/krnet/temperature_600.jpg The air temperature at the time was 92F and readings were taken at one minute intervals until they became stable.. 0 1 2 3 4 5 CF black 79 137 142 144 146 145 CF white 74 110 119 118 118 118 0 1 2 3 4 5 6 7 8 9 10 CF flox black 82 116 127 129 134 139 138 140 141 141 141 CF flox white 74 103 109 109 109 110 112 114 114 115 115 0 1 2 3 4 5 FG clear 78 117 114 114 116 113 FG white 73 109 108 109 110 108 I am not drawing any conclusions at the moment but I was amazed at how quickly peak temperatures were reached. Cheers -- Darren Crompton AUSTRALIA My web site: www.kr-2s.com
