<September 12, 2007>
Longeron Downward Bend and Twist
It was bend and twist night here at the RV7 factory. I finished the longerons by putting the downward bend and twist on the front of each. I am glad to be done with these. Itís not that they were hard, just a little annoying. RV-7 builder Mike Bullock gave me a suggestion, and that was to bend the longerons in short sessions rather than trying to do it all in one day. Thatís exactly what I did and I think his suggestion worked well for me and my personality. Thanks Mike.
Clamped and reading for a beating! The small clamp was put on to keep the longeron from moving out of the vise when I pounded on it.
After a couple minutes of stress relieving hammering, the bend was complete. I used my digital level to get as close to the 5.6į called for in the plans, and wouldn't you know it, it was perfect from the first attempt when compared to the fuselage skin.
Once I was satisfied with the downward bend, I used my adjustable wrench to put the prescribed twist into the longeron. It amazing how much you have to twist this around to end up with 17į of twist. I got it as close as I could, but I am not too worried about being exact here as there is plenty of play to adjust things as needed later.
I repeated the process for the right, and wouldn't you know I got it almost perfect the first try. What is going on here tonight?
I then marked the canopy decks for trimming as is required for a tip-up canopy, but I am going to wait to trim these until the fueslage goes together.