Torquing Wing Spar Fasteners

The AN3 fasteners used on the wing spar are 10-32. The Standard Aircraft Handbook calls for a torque of 20-25 inch-pounds. I set my torque wrench to 23 inch-pounds and torqued all of these fasteners. The AN4 fasteners used for the attach fittings call for a torque of 50-70 inch-pounds. For these I set my torque wrench to 60 inch-pounds. Once I torqued all of these I checked to be sure that not more than three threads were showing. After checking the threads I applied torque seal to each of the fasteners. Next, I started to setup for the assembly and riveting of the wing. I put my bench extensions back on the bench to allow me to assemble the spar with the tip ribs pointing at the floor. In order to leave room for the rivet puller I started by setting up the outboard ribs first. The rivet puller needs to work on the inboard side of the ribs.

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