416 hours on the hobbs - happy new year brings a completed elev frame!

Happy new year to all who venture on to my site! Wow - what an eventful past few days around here. I had prepped the parts and was ready to prime on 12-30-11, but that day the winds were howling at 50 plus mph throughout the entire state of Colorado - not a good day to try to prime anything in the windy garage, so I waited. Then I had to partake in all the holiday festivities on New years eve, so we went downtown to watch the people get drunk and check out the fireworks. Got some really cool flashing light 2012 eye glasses too.

New years day was a treat. Got the parts primed in the morning, and then went flying with Kevin in the afternoon. What a wonderful flight - smooth as silk and hardly any wind, and a beautiful sunset to round out the day. A great way to ring in the new year.

Fast forward to today - FINALLY got a good solid airplane-building day in the books. Started where I left off over a week ago when the first rivet attempt of the tip rib met with disaster. I am happy to report that todays activities had much better results.

With a lot of careful planning and thinking things through, I changed my approach to dealing with several of the rivets of the left elevator frame this time. The first step was deciding to use gravity as friend when working with the hand squeezer to attempt to set the An470 rivets on the flanges of the two tip ribs to the main spar.

It starts with setting the frame parts on the bench with the E704 counterweight rib clecoed to the spar. (Get ready for  aton of pics and another very long post!

Click on the pic to enlargen it to show more detail. I have a small thin piece of 3/4 inch plywood about 2 feet long that just fits inside the web of the spar in between both flanges. I aso have two other smaller pieces of 1x2 that will fit in certain areas. I used these pieces of wood extensively for this and many other building/clamping scenarios. The 3/4 inch wood is just thick enough to allow the flanges to sit above the table to you can clamp the crap out of everything  and not damage the parts. I recommend sandwiching the parts between 2 pieces of  wood as much as possible. I then clamped everything to the drill board, with the end of the spar hanging over the edge just far enough to clear the clecos, rivets, and hand squeezer/rivet sets. The E704 is facing up as shown, and is clecoed from underneath and the sides.

I used a 1/2 inch long x 3/8 inch wide flat set on the bottom, and the 1/8 inch x 3/8 inch round headed rivet set on the top of my flange yoke. Oh yeah, I had also managed to grind down the glange yoke a bit more, but after todays exercise I find that I need to do it even more. Ya gotta make custom tools from time to time.

I put masking tape inside the round headed rivet set to help prevent smilies - works fantastic. Apply the tape to the top of the set, mush down the middle using the head of an AN470 rivet, then secure the tape over the sides of the set, and take an Xacto knife and trim the excess tape off. be careful not to cut yourself.

Next is looking down from the top of the E704 rib. ONe cleco holds one side of the flange, another cleco holds other far side attach point, and the rivet is placed on the rib side of the assembly to froce the rib flange tight against the web of the spar. The principal of this apprach is quite simple: allow gravity to force the rivet set on top of the rivet head, hold the parts together, and make it easier to set the rivets using the hand squeezer.

Here is a shot with the rivet shank extending out the bottom

Next is a pic of the hand squeezer in position. there is a trick to fitting it inside the flange when using the longer 1/2 inch rivet set. You ahve to leave enough room to allow the sets to slide over the outside of the spar flanges to get it into position. Then, if you need to, you can screw or unscrew the adjustable set holder to get the correct distance between the two sets to smash the rivet. If in doubt, start with the rivets sets slightly too far apart - just enough to thicken up the rivet shank to allow you to get an idea of how much further you need to adjust the set holder to get the proper shop head on the rivet. This is known as "dialing in" the rivet sets to the correct depth.

You have to get the thich part of the yoke to sit on top of the spar flange in order to allow the AN470 rivet set to position itself over the dome-headed rivet properly. The magic of this arrangement/method is that gravity is now holding the parts together and the rivet set on top of the rivet, so you don't have to work as hard to keep everything in alignment. No matter what anyone says, both the hand squeezer and the pneumatic ssqueezer are very heavy and awkward tools to work with. Anything you can do to make it easier to work with either of these tools is a huge plus. The other magical thing about this is that it makes it much easier to align the rivet set on the bottom to ensure that you are setting a perfectly straight rivet.

Here is a shot of the rivet after it was set:

This next one is a little blurry, but it shows more detail about how the sets are aligned on the rivet once the squeezer is placed into the correct position. You can check to ensure that the dome-headed rivet set is properly positioned over the rivet head by looking at it through the opening in the corner of the rib and the spar. Then you can check to ensure that the bottom flush set is centered on the rivet shank so that you won't risk clenching the rivet over to one side or the other, and will drive it straight down the center line.

WHEW! Previous problems all successfully averted. Both rivets for the flange of the E704 rib are set successfully.

Now on to the E703 tip rib. Although not seen in this pic, I ahve another piece of wood underneath the tip rib, and then the one top, and the clamp is sandwiching the web of the rib in between the two pieces of wood. This allows me to clamp it tightly to the bench. I had to leave some of the clecoes that join the webs of the two ribs off in oder to fit the wood in place, but the clamping helps to keep the parts together as they are supposed to be. The two copper clecoes on the far right side of the the next pic are the ones that are holding the flange of the E702 spar to the back side of the tip rib. This is the next area to be riveted. The E702 spar is now sticking straight up. I did not need to support it with anything, but a helper here is advisable to keep it from flexing too much.

Next is a really bad pic - trying to show the flanges and how they are sitting against the rib. Still not exactly flush but definitely flush at the point where the rivets are being applied, so all is good here. Also notice how the bottom if the rib flange is sitting just above the top of my drill board. Make sure you are not crushing the flanges of anything when you clamp the parts to your bench.

Here is the flange after both rivets have been set. Still not the best, but it is acceptable.

With both end rib flanges successfully set, time to attach the webs of both ribs together. This was a very interesting adventure, adn I ended up doing it almost completey differently from the way i did the right elevator. Here is the setup on the end of my work table:

Now to elaborate on this a bit. When you get to this part, you basically have to be able to get a squeezer to fit in between the 2 flanges from both ribs. This equates to a little more than an inch or so. This is why I decided to buck these "rib-joining" rivets on the right elevator instead of squeezing them, because I could not bring myself to accept what I was going to have to do in order to try to get the flange yoke to fit inside this assembly. After thinking it through a bit more, I decided to give it a try with the squeezer. I changed sets by removing the 1/2 inch long flat set and replacing it with the 1/8 inch x 3/8 inch flat set. This was necessary to allow enough room to insert the yoke between the two flanges of each rib.

The trick is that you cannot set the adjustable set holder on the squeezer to the proper depth, because you are not able to fit the rivet sets over the flanges of both ribs. Instead, you ahve to start by screwing down the set holder far enough to allow you slide the rivet sets over both flanges - long side first, followed by the short side. Then you ahve to position the sets over the rivet adn adjust the set holder back out (unscrew it) to get it to the proper depth. the last pic above shows the squeezer handles resting on the back of one of my card table chairs, which just happens to sit almost flush the clamped assembly on my work table. I used the chair back to support the the squeezer handles after I had adusted the sets to the proper depth. Zyou cannot remove the yoke until you reverse the procedure described above to widen the sets far enough out again to remove the squeezer. The chair method between rivets worked out great.

Next is the Squeezer in action as I set each of the rib rivets.

So no I did not use the gravity method for these. the main reason is that this area is open enough so I can clearly see if the rivets are being set correctly on both sides while I squeeze them. I will also take this opportunity to report that setting AN470 structural rivets with a hand squeezer is very hard work. I chose not to try ANY of this with the pneumatic squeezer because it is just too heavy and bulky.
Done with these rivets:

Next were the support plates and K1000 nut plates to the back side of the spar. I did these slightly out of step as I wanted to ensure that the tip ribs went on OK before thinking about doing anything else.

I basically used the rivet gun and my thin man tungsten bucking bar to set thise rivets. I set all the top or mid-level rivets, then turned the spar over, reclamped it, and set the last six rivets shown clecoed above. I seem to ahve found that using the smaller bucking bar works better for me when I set the rivets for support plates. The rivet callout turned out to be a bit long, and squeezing these rivets here usually ends up with clenched rivets that must be drilled out adn redone. If I buck them I find I ahve no problem setting slightly longer rivets.

Small end of the spar:

...and the larger end at the root:

Next I used the no hole yoke to set the 4 flush rivets at the root that attach the forward flange of the root rib E705 to the E702 spar. Those came out fine.

12 more structural AN 470 rivets to set to attach the control horn to the frame adn I am all but done for the night.....

And some shots of the back plate rivets all installed....

What a relief to be done with the frame finally! tomorrow I should be able to start attaching the frame to the skin. I also need to set the trim support bracket rivets a bit better as my back riveting did not turn out as good as it should be for those rivets. Also, I have offically maxed out the memory on my 2 GB SD camera disk since I began taking pics of this project in May of 2009. I got another one for Xmas so disk one goes in the file and I start a new chapter of the build on the new disk. Fitting for the beginning of a new year I guess.

Still several steps to go to finishn the tail feathers, but getting ever so closer now.......