October 5, 2007
Ribs
OK... last time we finished up the spar caps so now it is time to move on to the rib work.  I am glad I did not try and scratch build these. Time is becoming more and more of a factor.  My wife is Pregnant again!  My goal is to finish the wings before the baby is born. This gives me about 8 months to finish them in, I am confident we can do this.  Wish me luck!!
I bought the gusset stock from Sonex. I think this must be a new item because I did not remember seeing this on other websites.  These are predrilled and cut to shape. Only thing left to do is bend the edges over per plans.   I did run into one issue with these. There are 4 different kinds of gussets, each kind has a quantity of 8  which equals 32 total guessts to bend.   My issue: W15-06 &-07 gussets, they came in the same sandwich type bag... initially, they looked like they are the same size and shape, you just need to bend 8 of them down, and 8 of them up.  Well, we found out that -06 is shorter and has different hole locations. What Sonex sent me was all -07's!  I called Kerry at Sonex and he informed me that this is how they send them out. You need to do some trimming to the -06 gussets to get them to fit, and your holes will not be the same as on the plans.  OK .. a little more work but doable.
With 32 guessts to bend, we decided to make a jig on the brake. You can see the scrap aluminum we used. You just place the gusset in the slotted area and bend it over. It took some trial and error to find the exact locationf for it, but in the end, it worked great. We used this triangular plate as the sandwich, it is thin enough that we are able to make 90 deg bends with it...  We did this set up different, initally, which you will see we used the thicker plate in the next pics, this worked fine, but it did not allow us to obtain a full 90 deg bend.
Here is another view of how we did it, initally. You can barely see the small slotted area where the gusset slide in to for the bend.
Slide gusset in until it hits the stop and bend it. There is no loosening or tightening of the clamps with the slots in place. Stick it in and go!
Longer side bent over first. Then the other.
After we discovered that this thinner, triangular plate allowed us to form a 90 deg bend, it is all we used.
This is the gusset that needs trimmed to fit.  See the red line on the gusset? It need to come off in order to fit correctly.
Trimmed the gusset to fit. The edge distance on one of the holes is too close, but Kerry said not to worry about it on this application.
All lthe gussets bent over per plans. Half are for the 4 front ribs (1-4), and the other half are for the associated aft ribs (1-4).
Next we had to make the cut-out's for the spar caps.  Each rib has its own amount of trimming needed per plans. We made a guide out of scrap aluminum to find our trim locations.  You can kind of see it laying on the plans at the 7 O'clock position from the brick. (Winds today were 25-35 mph with higher gusts!)
Better pic of the guide I was talking about..
After the cut out.
This is the back side of the rib. You can see by my red marker where the gusset needs to be trimmned down some more. Remember, these are the ones Sonex sent with their "gusset kit." If you made them per plans, yourself, you probably would not have to do this.
I only trimmed a couple of them tonight. Here I am polishing/deburring them with the Scotchbrite 3M Combi-S wheel.
Here is where the gussets go on the front and aft ribs.. stations 1-4 only.
Look at all your ribs for flatness. This rib was NOT typical. Most of them were pretty flat, not needing anymore work. But on this one, I had to bust out the fluting pliers.
Very light pressure is all that it takes to get out the worst bow... be careful!