First task was nice and easy. Completing the push rods. A few more MSP-42 and they were done. Then safely stored away. Might setup the wing bell cranks tomorrow.
Then back to the elevator trim tab. You may recall that I had problems with the aft most rivet on the trim horn. The overwhelming response on the list was pop'em and move on. I decided to use a MK-319-BS rivet which has a AD3 countersunk head (rather than a CS-4-4 with an AD4 head).
The MK-319-BS rivets have a diameter of 7/64", therefore a standard #40 drill isn't big enough. We ended up using a #34 drill which was a nice snug fit. The finished results looks fine. Next time I would start with the pop rivet option.
With the new knowledge about the M-319-BS rivets, I noticed the rear spar of the left elevator also uses these rivets for the outboard locations. I match drilled these to #34 also before we moved on to the black death stage....
Then it was time to start the Pro-Seal fun and games.
We started with the elevators. Took all the skeleton structure out of them and removed the dust from the internal corners.
Dad then starting the mixing process, 10:1 by weight. We ended up with about 3 ounces of mixture which just did both elevators.
The blob of goo was put between each pair of stiffeners.
The two elevators didn't take that long to complete. After the goo was in, the skeleton was re-cleco'd together and we left them standing vertically for about an hour to let the Pro-Seal settle a little before setting. Tomorrow I'll try to finish off the riveting.
Next up was the rudder trailing edge. Another mix of about 3 ounces worked well. Pro-Seal is a bit like sugar syrup or condensed milk, 'stringing' and very sticky. A second person on hand is very useful.
I un-cleco'd the trailing edge wedge from the rudder and used acetone on the skin surfaces.
I then held the skins apart just enough for Dad to be able to spread some Pro-Seal at the end of each of the stiffeners. We used little spacers every few ribs to hold the skins apart, otherwise the skins set together (without the wedge) and are difficult to separate again (don't ask me how I know!).
Then a thin layer on both sides of the wedge.
This all comes together as a sticky, gooey trailing edge.
You can see each of the stiffeners have pro-seal top and bottom and these meet when the skins come together.
I then moved up the trailing edge cleco'ing every hole. The AL angle worked well keep the surface flat and straight.
Before using each cleco I dunked it in Acetone. I'm not sure if this is just going to help the pro-seal stick to the cleco or help assist being able to remove the cleco later - we will see.
The finished edge with the skins cleco'd top and bottom as well. I also ran along the edge squeezing (with a cleco clamp) the skins together. This helped compress the extra pro-seal and it oozed out of the trailing edge and reduced any gaps between the skin and wedge.
The lower end. You can see how the Pro-Seal has formed a neat cushion around the stiffener. Now we have to leave the trailing edge to set before we start the riveting process.
To finish the day I went back to the wing aileron push rods. After a few suggestions from various sources (thank you for the emails) I tried some different options. The most successful of which was using the C frame. I used the AN470 rivet set in the lower position with the flush bar coupled with the back riveting set on the rivet gun. The output was better and more consistent rivets however I'm still not particularly comfortable with the results. One of the newer options that VANs has recently detailed is welding the parts together. With all steel components and the lack of space / structure to rivet I like the idea of welding. No decision needed right now, but something to add to the list to think about.
Early finish write up and social activities with the UK visitors.
