I managed to sneak in a couple hours of work this afternoon. Tammy was getting Acacia ready to go to “Nanas” house so we could have a date night. So, I figured I would try to get a little work done while she was dropping the baby off. Tonight is pretty much a repeat of last night, except on the right wing. I managed to complete this wing a little faster than last night since I was familiar with what to do. It seems like this will be par for the course on building the wings: Learn from one side, and then you can do the other side a little faster/better.
I started out by clecoing all the ribs the right main spar, being sure I transposed the handed-ness of the ribs. Van’s only gives us the left side view of the wings, so they leave it up to the builder to be smart enough to “transpose” the layout for the right side. For example, a W-709-R (RIGHT handed inboard main rib) shown on the plans for the LEFT wing, actually would be a W-709-L (LEFT handed inboard main rib) for the RIGHT wing. Once you look over the plans and see how it goes together, its actually not as hard as it seems (trying to read from a blog post and do the figuring in your head makes it…weird. heh.).
Once I had all the ribs cleco’d to the main spar, I clecoed on the rear spar, double checking its orientation.
Now, it was time to match drill the main ribs to both the main spar and rear spar. That was simple enough, and didn’t take too much time. The last thing left to do was to cleco on the leading edge ribs, again, double checking the orientation and proper handed-ness and then match drill them as well.
VOILA! I have another piece of kit that looks like a wing should look! I still haven’t fully decided on what to do for wiring, but I still have some time. However, I think I may actually move on for now and start building the flaps and ailerons and leading edge skins. Its currently winter time in Tennessee, so my workshop is hovering around 60 degrees, which can making working with ProSeal (for the fuel tanks) and bit challenging. Spring and summer are only a few months away, so I will hold off on my fuel tanks until warmer weather. I am also considering doing the same for the wing stands. I think I would like to build the control surfaces while I have plenty of room in the shop. If I build the wing stands, I will loose a good bit of working area in the shop, so I will ask the experts on Vans Airforce if there are any gotchas to skipping ahead and building the control surfaces ahead of the stand and tanks. At any rate, here is all the photos from todays build session:
Google Photos Link: https://photos.app.goo.gl/Bx5tJyDEThlWKNPu1
Hours Worked: 2.5
4 months. Thats how long it has been since I have done any major work on the RV-7. Between work and family and then holidays, I really haven’t had much free time to get down to the shop and build. Having some time off for the holidays, I decided to put work and learning aside for a few nights while I am off and get some work done on my build. I only have a few ribs left to straighten and then flute, and they were the leading edge ribs.
These guys were a bit more tricky because of the curve on the leading edge, and I had to refactor my flange straightening tool so that it had a smaller “bite” to allow me to not mess up the very nice and sleek compound curve in the top of the leading edge. You can see how much smaller the anvil is on my flange bender in this photo:
In the bottom left of that photo, you will see the new anvil I cut from some spare oak I had left over from the first, wider, anvil. This worked great, and didn’t cause any warping or mis-shaping on the top curve. I did all the rib straightening down in the shop on my bench, and then moved my stack of ribs upstairs so I could use my wifes granite counter tops as a perfectly flat surface to do my fluting to bring the ribs back into flat.
Heres my finished stack of leading edge ribs, with their perfectly 90 degree flanges, ready for fluting. Notice how much warping there is from the forming process. This is why we flute the ribs:
And after about an hour and a half of fluting, I ended up with a nice flat stack of leading edge ribs.
Some needed a bit more than others, but they are much straighter and flatter now. I might have to do a little more here and there once I start mounting them on the spars, but I’d say I was able to get them 99% of the way ready. FINALLY I have all my ribs done. All the flanges are at 90 degrees, and they are all fluted to be as true as possible. This was probably the most boring work I have done so far, and I am SOO SOO glad I can move on to something else. Heres all the photos from tonights session in one album:
Google Photos Link: https://photos.app.goo.gl/0DF6VPiHYHkbKkjQ2
Hours Worked: 3.25
About a week ago, I decided to bring my wing ribs upstairs and do the fluting up here, since that doesn’t produce any filings or shavings. HOWEVER….I have had a lot going on family wise that I haven’t been able to spend much time on them. I’ll also admit that over the last few days I have actually been fiddling with these things to the point of frustration. I tried a few times to sit down and get the straight using the wood dining room table as my “flat surface”, and always end up frustrated because no matter what I tried, they never would come out straight.
You see, we have to flute the flanges on the ribs because during the forming process they will get bowed a bit. Fluting “shrinks” the metal down along the flange, pulling it back straight. See how they are from the factory:
It seems like a simple process, and it actually is…..if your reference surface is truly flat. 😐 Turns out, our dining room table is not exactly flat, and I was using this bowed/curved surface as my guide and my ribs never came out right. Once I realized this, thanks to my wife Tammy, I decided to use our granite counter tops, since I knew they’d be nice and flat. After switching over to the stone counters, I ended up using the “table top” method of rib fluting. This video shows how to do this method: https://www.youtube.com/watch?v=pIvFpVV6kIQ
The results speak for themselves. After I did the table top method, with the flanges sticking up I flipped the rib over with the flanges down towards the counter top to double check. Then I used a metal ruler to measure that the rivet holes were all in alignment. Some ribs (like the one below) only needed a couple of flutes, while others needed many more.
I ended up getting the process down pat, and was able to knock out 14 ribs using the granite counter to and “table top” fluting method. I did have to go back and re-do the ribs that I did on the dining room table, since they were not straight. I’ve got a lot more to go, but I think this method will help me knock them out quickly. Here’s all the photos from tonight’s work:
Google Photos Link: https://goo.gl/photos/pc9q3jqyrzesHnzn9
Hours Worked: 2.75