Elevator work, counterbalance weights and Priming - 11 hours

I managed another big day. I set out working on the elevator spars and counterbalance ribs. First I match drilled the spar/double/reinf. plates on each elevator rib. Then I worked on the counterbalance ribs and skin. Everything went exactly according to plans and instructions.

 When it came to the counterbalance weights, The instructions call for you to use the holes in the counterbalance skin as a guide to drill the holes into the weights. As this is fairly thick material, I figured that it would be best to drill a pilot hole in the weights before I match drilled them in the assembly. I was happy with the result. The #12 holes leading into the counterbalance ribs were centered with good edge distance, bit close to the inside but acceptable. I will watch to ensure the nut does not put pressure on the inner radius of the flange.

I then when to work on shaping the lead counter balance. I marked out the one weight to cut and used my sawzall to take the majority of the excess material off.  I then used a wide selection of files to bring it to its final shape.

I've done all that I can...now I have to prime. Yuck!!

So I then set up the garage and primed a few more parts!

Countersunk the new electric trim plate - 2 hours

I spent a little time on the new trim plate that I received. I countersunk the holes to accept the smaller 425AD3 rivets. I countersunk them with the de-burring tool. I was cautious but it turned out well.

Worked on This and That - 7 hours

Today was the first big day on the plane in quite a while. I managed to order a few needed parts and tools last week, which put me back on track for the project. First off I got to work on the VS808pp spar doubler. This section has given me a bit of grief for a variety of reasons; 1 - Countersink depth, which is a little bit of a trick to get. 2 - Setting those rivets that are in the VS-410PP brackets that are soo close to the vertical portion of the bracket. 3 - Removal of poor rivets is extremely difficult through the thick material. I've wreaked a piece trying to punch out a rivet, without the use of the handy tool that I was told about after the fact. So...Round Three...Here we go.

I set out by cleaning up the entire piece...Something that I have now mastered. I used a Dremel with a small sanding drum on the holes and on the inside radius's. I then used a file to break all other edges.

I then set up the countersink using a test piece that I have made and dimpled. The correct setting results in a countersink depth so that a 426AD4-X rivet sits just ever so slightly below the surface of the material being countersunk. Note to self: Order more countersink cages!

Now, on to the next piece, The rudder counterweight. Again the original one was countersunk way too deep. Changed the bit on the cage and re-set up the countersink. After much monkeying around, the proper countersink was done. Note to self: Order more countersink cages! I tried to mark out the area where the six rivets on rudder counterbalance rib interferes with the weight. Note to self: Next time mark the six rivet holes on the weight before you set rivets into the counterbalance rib.

I then used files to remove areas of the lead weight that interfered with the counterbalance rib and rivets. I also cleco'd on the horn brace.

Next, I moved on to the elevator trim.  After reading a few build logs about hove everyone notices that the dimension callout of 1-3/8" is wrong (See Electric Trim Assembly Detail on drawing #4). I found that a dimension approximately 1.275" is closer to the correct one. 

The above picture shows how the trim sits if I used a 1.375" dimension

The above picture shows how a reduced dimension allows the trim to sit centered in the opening.

Building tools

A handy tip that I learned from one of the guys at the EAA meeting is to build some guides for both drilling operations and rivet removal operations. A little drill guide using a piece of round bar with either a #30, or #40 hole is a handy tool that ensures that when drilling a hole with a hand held drill, the drill bit is perpendicular to the piece. If you can have a tab welded to the side it will allow you to have a place to use a clamp on it.

A similar guide is great for using under a piece when you need to use a punch to remove a rivet.  The trick is to have a hole in the tool that is just slightly larger than the shop rivet head. If you ever need to punch the rivet out, the tool used would support the aluminum around the rivet and is helps you avoid bending the aluminum while driving out a particularly stubborn rivet.

I had ordered a few round bar pieces last week. All were 2" long and I got some 1" diameter and some 1-1/2" diameter. In retrospect....the 2" length is just too long.

I think I will re-order some pieces that 1" long and get some 1" dia, and 1-1/4" diameter. and use those as my drill guides. (Update....This is an excellent size 1" diameter and 1" long. Drill some on center, and some off to one side. The ones drilled off to the side come in handy for those tight areas)

I decided to use my 2" x 1-1/2"dia piece to make a guide for punching out AD4-X rivets. Driving these rivets out of the thick spar doublers has been a cause of much frustration for me. Hopefully this tool will safe grief for me in the future. I started out by marking center on a piece. I then set up the drill press and made a pilot hole with a small 1/16" bit.

 I then enlarged the hole with a 15/64" bit. Turns out that this hole size will allow removal of both a AD4-X and AD5-X rivet.

Time to get organized...More

I decided to take some time and get some organizing done. First thing I wanted to do is color code all my dies and tools according to size. I notice that often I waste time double checking sizes, and I dread the day that I use the wrong size on an important part. I raided my wife and daughters nail polish and went to work. I then made an excel spread sheet to list the colors to the sizes as a quick reference.

Odds and Ends - 2 hours

I asked Mike a friend of mine over to give me a hand with the rudder. Mike has way more experience than me and he suggested perhaps trying to set the rivet with a Cleveland Tools Big Squeeze. He says that he prefers it over a pneumatic squeezer as it allows him to control the squeezing of the rivet, and also allows him to stop squeezing if the rivet is starting to bend or shift. He says that's its slower, but he finds that he likes it way more. Mike suggested that we give it a try on the stubborn rivet I have on the rudder.

Well what can I say...It worked exactly as he described. We slightly bent the top tab of the rudder spar to help with accessibility. I held the rudder and a flashlight as Mike works the Big Squeeze. The rivet was perfectly set!

We then worked a bit on the Vertical Stabilizer to drill out some of the oops rivets that I had used on it. Originally I used a 4-3.5 oops rivet to replace a 3-3.5 rivet which is incorrect. I needed to use a longer oops rivet length due to the oops rivet having a larger diameter shank diameter. While removing a rivet, I bent one of the tabs on the rib where it attaches to the front spar. No big deal, I pulled out my 3145 RTV adhesive and put a dab on the tab. I then clamped it and I am waiting for it to dry. This will allow the tab to sit back tight against the spar until I can set a rivet through it.

Mike has some really great tips and is an inspiration to get building again.