So Facebook reminded me this morning I hadn't posted to the blog in a little while but rest assured I've been busy at the shop.
First I had to tape together each of the four sections of wing rib templates and make sure the matched the plans. I used the form template as a rough guide and pinned both to the table for measuring:
After confirming the template is exactly as per the plans, I unrolled a sheet of 0.025" sheet and traced out 12 rear wing ribs and 2 root ribs. It's a bit of a challenge to arrange them to minimize waste:
It took about an hour, but I managed to get the big sheet cut down to manageable size then separated each of the ribs as rough cuts using the bandsaw:
Lots of final trimming and edge sanding in my future!
Work continues on my forming blocks. Now that I have them cut out and sanded to final size, the next step is to router a 1/8" roundoff edge on the inside (metal facing) edge. This prevents the aluminum from bending too sharply:
Next, I needed to figure out a way to bevel the outside edge of each form to create springback relief. Aluminum, particularly thinner gauges needs to be bent 6 to 10 degrees past 90 degrees in order to spring back to the intended angle. Turns out Ron still has the table adapater he made for his forms:
Here you can see a nose rib form sitting on the adjustment table just before I sand away the springback angles:
Here is a good picture showing the nose rib forming blocks, stacked as they would be in use. The routered edge and springback angles can clearly be seen:
Just to confirm everything matches up, I placed the aluminum nose rib blanks between the form blocks for a picture.... perfect fit and ready to start bending soon!
Encouraged by my success, I continued onwards with the rest of the form blocks for the tail group and they too are ready for bending aluminum blanks. Really pleased how these turned out:
Work also continues on the 701 wing repair. As part of the tip extension, two new full ribs will be inserted between the last factory rib and the wing tip. The necessitates cutting back the original rear rib channel:
Trimmed of the flanges of the existing rear channel leaving a long tab that will attach to the new wing rib we are inserting at this location. Once I have the wing rib in final position, this will be trimmed accordingly:
This new ribs will form the support for the wing skin extension joint and a second rib will provide the outermost structural pick up point for the extended flap and slat lengths. Here is the first extension rib test fit in place:
Next up, figure out where the second rib needs to be by determining where the outermost flap and slat pickups will be. Once I know that, I can make a new rear channel and also decide on the second part of the spar cap/web inner doubler. It will have to be attached to ribs too.... phew.
Progress... back to the shop again for the day tomorrow, hopefully to finish off the wing rib blanks and the wing rib form blocks. Thanks for visiting!
Husband, father and 911 dispatcher. Long time pilot with a licence that burns a hole in my pocket where my student loan money used to be. First time aircraft builder. Looking to fly my own airplane.