February 18, 2015 – Well, it was time to do the conical bends. This is a transition at the aft corner of the sideskins to the belly. The sideskins have an “ear” that has to be bent, or mare accurately, rolled, to fit the contour of the fuselage.
I took off the right sideskin, and put it on the table. The biggest fear here is that the forward corner will crack because the bend radius is quite tight. I deburred the relief hole and the edges to alleviate against cracking.
I took my cues from other people’s websites, and set it up as follows:
I drilled a piece of scrap angle to the holes on the edge of the skin at that “ear”, and secured my bucking plate to the skin and the table at the bend line:
I gently started the roll. I used a crescent wrench on the end of that scrap angle, although I found that it was generally just as effective to do the bend by hand.
I rolled it past 90 degrees to allow for springback. The only problem I was having is that the end cleco nearest the small radius bend was pulling. You can see that in the picture above.
Here’s how it looked when I stopped rolling:
No cracks.
I fitted the skin back in place. The clecoes all went right in, which is good. I don’t really like the forward end at the small radius. I’ll rework that for a smoother transition later on, but I’m generally happy with this side.
Time: :45
