A new first was the use of a little present that I got from Mike Rettig a while back that I had not yet had the chance to use. It is a pneumatic blind rivet puller from harbor freight. This little tool (well, it is NOT so little, as you will soon see in the pics) worked wonderfully up to a point, and then I had some issues that seemed to resolve themselves somehow. I was able to use it on all the rivets on the LE except for the one closest to the outboard tip on both elevators. That last rivet is tool close to the counterbalance skin and ribs to allow it to be used, so you ahve to revert to the hand squeezer for that one. More to come on that topic in a bit.
Here is shot of the right elevator all buttoned up. Came out OK.
I have one episode of a rivet that did not set correctly. I had to drill it out and set another one, and then I noticed something really disturbing about the AD41 ABS pop rivets I was using. Many of them seem to be missing the mandrel on the end, and I can't tell for sure if this is by design or if this is a flawed pop rivet. I am not even sure if the one that failed was one that had the missing mandrel tip or not. Basically what happened is that the mandrel never broke off as expected, and it continued to pull all the way through the hole. Turns out there was a tip on the end but it never broke off. I'll get a pic of that tomorrow.
Anyway - the pneumatic rivet squeezer works pretty slick. In one trigger pull it sucks the rivet stem up, sets the rivet, and deposits the stem in the back of the tool in a nifty little catcher. The action is very smooth and about 99% less violent than when i breaks while using the hand puller.
Here is the manual puller on the left, adn the pneumatic puller on the right.
Since I had a bit of a problem with burs in the holes that I drilled on the right elevator, I decided to take a different approach on the left elevator by using reamers to create the holes for the rivets. The process basically went as follows:
1. Cleco the holes and use duct tape strips in between the clecoes to secure the top and bottom skins together to maintain the hole alignment while the rivets are being set.
2. Ream the holes with a #40 reamer. They are already punched to #41 hole size, so the #40 reamer will work perfectly as a starting point.
3. Drill the holes with a #31 drill bit to prepare the hole for the #30 reamer, which is the final size that is required to fit the pop rivets.
4. Ream the holes with the #30 reamer.
This process left very clean holes with essentially no burs to worry about.
This next pic shows the #30 and #40 reamers, and the #31 drill bit.
Next is a pic of my 12 inch long extended #30 and #40 drill bits. I needed to use both of these for the last hole next to the tip that mentioned earlier, because you also cannot get a drill in there to safely drill out the last hole without risking marring up the counterbalance skin with the chuck on the drill. This method or an angle drill would probably work OK.
Next is the left elevator, inboard section has already been drilled and riveted, and the remaining sections are clecoed and taped as desribed earlier.
Next is the inside of the inboard edge of the right elevator The skins have mated much better than the way the rudder turned out, which I now admit I will most certainly redo, now that I know what I need to do to make the skin form correctly.
And finally a shot of the outboard section on the left elevator. Note the copper cleco for the #30 hole that I have already drilled with the extended length drill bits.
I managed to rivet everything on the left elevator until I got to the last hole. Then I started having problems inserting the stem of the pop rivet into the manual pop rivet gun. I had to stop because I had no way to set the final rivet. What a fitting end to this long drawn out episode of the build. Just seems like it wants to keep scratching and clawing its way against your every move. I wanted to be livid about this, but instead I guess I was resigned to the fact that this was probably going to happen anyway, just because of the way the elevators have gone thus far. So I stopped and went to a movie to regroup.
I then started looking over the rivet puller. I even disassembled the damn thing trying to figure out why the rivets would not insert into it. I finally found a small sliver of metal that somehow had imbedded itself inside the adjustable head that screws into the rivet puller for the correct size rivet you are using. So it wasn't a problem with the insides of the puller itself - just some junk aluminum that somehow found its way inside the small hole of the insert. It's too late to set the rivet now, so I will finish it up tomorrow. At least I now know what to look for, and I also know a bit more about how the puller is assembled.
Rod end bearings will be next, and then drilling the center bearing hole in the control horns.
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