Assembly

8/04/2011
Hours: 1.5
Assembly 24.5

Finished the modification to allow the lower rudder fairing to be removable.  The plans call for pop rivets but I decided to follow what some other builders did and install nut-plates in this fairing so that it can be easily removed.  I don’t think I’ll do the same thing with the other fairings in the tail, but this one needs to have a light installed in it later.  Now it can be removed easily and reinstalled which will allow the light to installed and maintained more easily.

I had some help in this from both Daniel and Zachary.  One helped me trim the fairing to fit and the other helped with riveting the nut-plates in place.
I’ve now done all I’m going to do on the tail section before we get into a hangar (several years from now).

Assembly

8/5/11
Hours: 9.5
Assembly: 23.0

Several little things here.  First, the wiring for the electric trim-tab servo is now complete and waiting for a cable to be plugged into it.  This of course will happen a very long time from now when the airplane is almost complete.  But I took some time to make it easy on myself later.  I bought some nice locking connectors, soldered the wires in place and mounted the connector in a spot which will make it “easy” to reach when the trim tab servo is mounted.  One thing I learned is that in the future, I’m going to get a wire crimper and connectors that take crimped pins rather than the solder cups.  Once the wires are soldered to the cups, it’s not possible to get the heat-shrink tubing around it.  This wasn’t a problem here since I slid the heat-shrink tubing on before soldering, but in the end, I could have used longer tubing for a better look and then another, larger diameter heat shrink tube over that whole thing to give it some more strain-relief.  This one is fine, but in the future, I’ll be crimping instead of soldering.

Also included the pin-out right here in this blog so that I’ll always be able to find it when I need it.  I do have the sheet I took the picture of in my airplane folder, but just in case I lose it, it’ll be here too.

Then Scott and I got the elevators fully attached to the horizontal stabilizer.  This was described in a previous post.  It was more of the same.  But now the job is finished.  Both elevators are aligned and had holes drilled into the control horns, etc.  They’re ready to go when we’re ready to go.  One thing I had to do was figure out how many turns the bearings could be backed out and still be safe.  I found out that they need to be fully engaged to the nut-plate that they screw into.  That means that all the threads have to be in play, so to speak.  I found this position by counting threads.  There are 6 full revolutions of threads in the nut plate.  This means that after 6 full revolutions of the bearing, all threads are in play.  This is the point at which the bearing can’t be backed out any further.  I then turned them in and counted the turns until the starting spot as indicated by the plans were reached.  I counted 1.5 turns.  To get the elevator to swing freely over the full range prescribed in the plans (30 degrees up and 25 degrees down) we pretty much had to back all but one of the bearings out that 1.5 turns.  When I checked up on this, I discovered that many of the other builders had the same experience.

Finally, I got back to the trim-tab anchors.  The plans call for these to be riveted to the cover plate.  But long ago, I decided to buy better anchors (it is agreed by most everyone that the anchors supplied in the kit are pitiful – just a nut welded to a flat piece of metal).  And apparently with these anchors, it’s very difficult to install the trim tab cables.  So others have done similar things to what I did.  I bought some self-locking pem-nuts (actually, I got them as samples from the manufacturer) and made little nut-plates to fit over the holes in the anchors.  I wanted to press the pem-nuts right to the anchor, but the hole required would have been too close to the edge of the anchor, so I made nut-plates with scrap aluminum and the pems.  Then I riveted these nut-plates to the anchors and voila, I have removable anchors.

Then I’m about to put the lower fairing on the rudder.  Because I want to put some navigation lights back here, I don’t want to permanently install the fairing with pop-rivets.  I found some people on-line who used nut-plates installed on the fairing in order to make it removable.   I have all the parts and will be doing that probably over the weekend.  Then it’s just build a cradle for the wings and wait for the wing kit to arrive.

Rudder

1/27/2011
Hours: 4.5
Rudder total: 40.2



Would have finished the rudder tonight if it weren’t for the fact that I don’t have a dimple die for a #8 screw.  Very annoying.  The leading edge is rounded and riveted and I did a nice job of it, too.  The counterweight and all that’s associated with that is ready to go.  I just need the dimple die I mentioned and then to put it together.  Got some help from Zach today.





Zach was a big help, handing me clecos and rivets and all.  He kept me company, too, by telling me about sponge-bob episodes and about his latest contraptions he’s made in his room.  Note that I had a lot of trouble with the tape-the-skin-to-the-pipe method and after struggling with it decided to just grab a 1″ PVC pipe I had laying around, cut it to size and match-drill it to the skins.  I then simply cleco-ed the pipe to the skin and used that to roll it to shape.  It really worked well!




 After the pipe was clecoed to the skin, I grabbed both ends of the pipe with a set of pliers as shown in the picture and twisted.  It takes some muscle, but I think it did a really nice job – and was easier (to me at least) and quicker (for me at least) than the tape method described in the plans.



Zach with his reflection holding the rudder in place for me.



The leading edge.  Pretty good job, I’m very happy to say.



Rudder

1/25/2011
Hours: 2.5
Rudder total: 35.7

Got the trailing edge done!  I’m very pleased with how it turned out.  It is straight to less than 0.0625″ (which is 1/16).  This is almost half the tolerance Van’s permits  in the notes (which states that the trailing edge should deviate less than 0.1″ from a straight line).  I measured this by laying the completed rudder on a flat surface (with the horn hanging over the edge) and measured the largest distance from the surface.  I would consider it a flawless evening of work if it weren’t for the one smiley I put in the skin as I hit the trigger a little too quickly while going over the rivets one last time.  I was very annoyed with myself about this.  Anyway, a good night of work.
Every other hole of the trailing edge cleco’ed to the angle iron.



A look at the rivets sticking up through the bottom.  After these rivets were set – first partially according to the plans and then fully with a back-rivet set, I turned over the rudder, cleco’ed it again and hit the manufactured head with a flat set.  Then turned it over yet again back to the side showing in the picture and hit the shop heads again with the flat set.  Then I taped rivets into the holes from this side – so that every other rivet was inserted from the opposite side.  Each time, I hit the row of rivets in a random pattern to avoid a progression of bending or something like that.  As others have said, I’m not sure it makes a difference, but I’d rather not find out the hard way that it does.  Also, I got sick of looking at those red markings and cleaned them off the metal finally.
On the rivets placed in the holes previously occupied with clecos, I repeated the procedure described above.  However this time, there were no holes to hold the rudder to the angle-iron (aka bucking-plate) so I got just about every clamp I own to do the job.  This was a pain because the vibrations from the rivet gun were constantly causing clamps to come loose.  I tightened them snugly, but I didn’t want to overly tighten them so as not to dent the rudder.



Once all the rivets were set nicely, I went over them all one last time with the flat set just to make sure everybody was as flush as possible.  All was going well until I got a little too quick on the trigger and caused this little smiley dent.  Argggh.  Always something to mess up an otherwise really good job.  Thankfully it’s not horrible and when its painted I don’t think it’ll be visible unless you’re really looking for it.  (the black things are marks I put to remember which rivets I hit as I jumped around randomly).



Nice straight trailing edge.
Our RV-10 rudder as it stands tonight.



Rudder

1/24/2011
Hours: 3.5
Rudder total: 33.2

Got other skin riveted to the spar (thanks to Laura for providing some help tonight).  Also finally realized how to prevent scratching up the spars and ribs when riveting the skins to them.  The picture below shows this high-tech method. …  Just put tape along the area where the bucking bar is likely to bump up against it.  That in addition to the tape on the bucking bar itself seems to do the job.  I got through the evening and added almost NO scratches at all to the counter-sink rib or the left side of the spar (the side I had left to rivet tonight).

In addition to all this, I prepared for riveting the trailing edge – hopefully tomorrow.  I’ve decided to go with the method I’ve read about where you use a piece of heavy angle iron and drill out every other hole with an AEX wedge as a guide.  Then you cleco those holes int he trailing edge itself directly to the angle-iron after taping some rivets into holes.  The angle-iron then acts as a bucking plate for the double-flush process as described in the plans.  I’m really hopeful that as many others I’ve read about, I’ll be able to get a nice straight trailing edge using this method.  The holes are drilled in the angle and the first set of rivets are taped in the trailing edge and ready to go.  …  Tomorrow…

Picture shows tape as I pulled it away after riveting the skin to the spar here.  Of course, I could have squeezed these rivets but I was in the groove.  I did have to replace one bad rivet.  The shop end of the “oops” replacement is visible in the lower center of the picture.  Most of the rivets were pretty good.  I do tend to over-set just a bit, but not by too much.

Rudder

1/23/2011
Hours: 5.9

Rudder total: 29.7

Made excellent progress today with the rudder.  Skeleton completely riveted together and left skin in place.  Wish I could do a better job not scratching the primer.  It’s better than with the VS, but still not great.  About 4 bad rivets today that had to be drilled out and a few questionable ones that I decided were better staying where they are than pulling them out.  My riveting skills are improving.  One thing to note regarding the far aft flush-rivet in the bottom rib on the left side which the plans say should be a blind rivet because it’s impossible to squeeze or buck a solid rivet in that position.  The blind rivet called out in the plans is too small a radius.  After I get it into place and did some work elsewhere, I realized the spot was empty, so I checked the plans again and put in another one which I was able to push right back out the hole after it was set (with the rivet puller).  I used one of the other flush blind rivet types that came with the plans which worked nicely.  If anyone is interested in the numbers which I don’t have with me as I type, send me an email and I’ll be more specific (joewilbur777 (at) gmail ).

Rudder

1/22/2011
Hours: 4.4

Rudder total: 23.8

Got stiffeners riveted to the skins.  The top rib, too.  Also have the doublers and nut-plates riveted to the spar.  Rudder horn is in place as well.



This is how I back-rivetet the stiffeners to the skins.  I got a back-rivet set from cleaveland tools that slides into their c-frame tool.  On the bottom (under the skin) is a flat set from a squeezer.  The rivet gun then does the same job as with a regular back-rivet set except I don’t have to hold it.  This job went really, really fast.  Scott and I put all the rivets in ahead of time and taped them down.  Then it was just a matter of bang-bang-bang, shift the skin, bang-bang-bang, etc.
This is Scott putting rivets in the second skin and taping them down while I was riveting the stiffeners on the first.

Me riveting the stiffeners onto the skin using the c-frame tool and the special back-rivet set.



The only real challenge of the day was this last rivet at the trailing edge of the bottom rib.  There’s no way I could get anything in there to buck or squeeze the rivet and did not want to use a blind rivet.  So I put the rivet in the hole and taped it.  Then I put a back-rivet plate under (not easily visible in this picture but the cleco clamps are holding to it).  I fit this chisel onto the shop side of the rivet and hit the chisel with the rivet gun.  Worked great … except that the skin jumped and I ended up setting the rivet with the head sticking out of the hole.  Oh well.  I’ve got plenty of practice drilling out rivets from doing the vertical stabilizer.  I drilled out the rivet and had to go up to a size 1/8 hole (AN4 rivet).  I used an “oops” rivet for this.  That’s a rivet with an AN3 head but an AN4 body.  That way from the top it still fits perfectly into the dimple, but the body is large enough to fit into the new 1/8 hole.  I did the same trick with the chisel, but clamped it down better to prevent jumping.  I had trouble getting the bigger rivet to set with this offset method, but I was able to get it set enough so that I could fit a bucking bar in and finish the job.



Nicely set rivet, but with all the efforts in the area I’m sorry to say I scratched up the primer pretty good.  Oh well.  I’ll touch it up before it gets hidden by the other skin.




Another angle of my nicely set rivet.  The bucking bar used to finish the job is visible in the top-center of the picture.  You can see the smaller shop-heads of the AN3 rivets down the line also.  …  You can see all the scratching, too.



 I like this bucking bar.  I have two others (including one made of tungsten) but this one gets into tight spots.  ….  I put the tape on to help prevent it from scratching up the primer, but it was too late since I already managed to scratch up the primer when I thought to do it.  I really wish I thought of it when I was doing the Vertical Stabilizer.  I scratched and mangled that up so bad, sometimes I wonder if in the end I might just re-order all the parts and do the VS over again.  …  Probably won’t but I do think about it.



Rudder

1/20/2011
Hours: 2.0

Rudder total: 19.4

Primed all the parts of the rudder.  I used the same stuff as last time, Moeller’s Zinc Chromate rattle cans.  This time, I didn’t worry about building an enclosure and all.  I set a few sheets of plywood down in the driveway well away from the house.  Then I roughed up all the surfaces really good and wiped it down with MEK.  I gave a good while to dry and laid everything out on the plywood web-side down wherever possible.  I sprayed the primer with a nice thin coat over everything then waited 5 minutes and went over it all again and repeated this until it looked nice and smooth.  Then I waited 20 minutes longer and carefully turned over all the parts.  Because the web-side was down, only the edges of the flanges came in contact with the plywood when I turned the pieces over.  No scratches from the plywood this time!!  I repeated the method described and let the pieces sit again for 20 minutes.  One by one, I carefully brought each piece back into the garage and inspected each part.  All but two stiffeners looked really good.  I placed those stiffeners back on the plywood and made them right.  There were a few places where I could have given it another shot, but let it go realizing that I was started to obsess.  Also, another coat on the skins would make them look better, but I didn’t feel another coat would protect any better.  They’re covered quite well, just with a little color distortion in some places.  This will be entirely covered so that really doesn’t matter as long as it’s protected from corrosion.





Rudder

1/19/2011
Hours: 3.6
Rudder total: 17.4



My replacement #30 countersink came in so I went back and took care of the steps I had to skip the other day.  Then I got everything dimpled (skins and skeletal pieces).  Then I built a little jig to make it easier to countersink the AEX wedge – which I then did.  Thanks to the many posts about this step on VAF (http://www.vansairforce.com), I saved a huge amount of time, no doubt.  Next is priming and hopefully I’ll do a better job this time than I did on the Vertical Stabilizer.



Closeup of some dimpled rudder pieces.



All the dimpled rudder pieces



The simple little jig I built to make countersinking the holes in the AEX wedge a little easier.  For those who care, the AEX wedge is a wedge of metal that brings the two sides of the rudder to a point at the back.  On the jig is a small piece of this wedge mounted so that when I put the long piece on top, I can keep it flush to the drill press.  There is a hole in the wedge to allow the countersink tip to have someplace to go as it presses into the wedge which will be laid above.  The nails are only there to loosely help guide the wedge as I slide it under the drill press.  The position of these nails are not critical.



 The AEX wedge resting on the jig under the drill press.  The countersink cage is visible.  One thing I realized is that I had to constantly check the locking nut on the countersink cage because the continuous motion of the drill caused to to loosen.



   

 

All the rudder – including the freshly countersunk AEX wedge all waiting to be primed.