Tonight I worked on parts of the canopy that will hold the plexiglass in place on the sides of the canopy. These little angles will have to get painted, so I prepared them as much as I can at this point for getting the Sandlewood sprayed over it.
I marked the drill spots according to the instructions, pre-punched them and used the drill press to drill through them. Put some wood behind it as the metal is thin and could warp if the drill just sees air behind it.
The next step was some preparation for the actual wiring section. I had read on VAF that a lot of people spent hours to get the guide thread through the control stick to eventually pull the wire for the microphone switch through. It appears that the shape of the tube with a 90 degree turn and some additional obstruction in there and the sharp edges inside the control stick is catching on to the thread and preventing it from following the tube to its other end. People used lead bobs, and pressurized air to push the thread through. One guy suggested vacuuming the thread from the other end.
It works!
Here's my modified version.
I used an ordinary thread. Nothing slick or a nylon line or anything. On one end I attached a 100 grain .32 wadcutter bullet (just some plated lead I had in stock) by drilling a #40 hole through the bullet and tied the thread to it. The reason is that the thread could try to fall into the tube while I am painting it. The bullet is too big to pass the obstruction in the tube and so I can shake the bullet back out on the desired end and hopefully the thread will still be attached. To increase my chances of the thread being still attached I added some glue to the knot. The bullet also helps to prevent the thread getting sucked into the vacuum as the bullet can't pass the obstruction.
Then I put a few inches of the thread into the tube on the side where the mike switch will go and put the end of the vacuum cleaner on the other end and turn it to maximum power. The thread gets sucked in best if you obstruct the opening on the mike switch side with your thumb to increase the speed of the air in that area. When the bullet is about to get sucked in, STOP :-).
It might be that the thread is not hanging out of the lower end of the control stick at this point but it should be really close and probably caught up on one of the burrs inside the tube. Get some tweezers and pull the string out, Voila!
It took me 5 minutes on each stick to get that string sucked through and tape it to the tube.
With so much time left after finishing way ahead of average time on this task I started some prep work on the servo installation which will follow right after the wiring is completed. There is a small mechanical task in section 44 and that is manufacturing the pushrods for both servos. It's not really difficult but took a about an hour to finish it up. Cutting the tube lengths, deburring, pre-drilling, taping the rods on both ends and cleaning up the mess where the subtasks. I think the challenging part here is the pre-drilling as the tube is quite thin and a canted drill could probably render the piece as trash. So I used a technique learned in one of the earlier chapters. I used an undersized drill bit that just barely fir into the tube. In my case the best I had available was #12 bit. I used this to adjust the position of the tube in the drill press. Then I replaced the #12 with a #3 bit and drilled that side. Remove, replace, repeat until done. I think the holes turned out pretty good.
Finally I put the bearings in there as well and adjusted the pushrods to about the right length using the 1:1 drawing in the manual.
Now I am waiting for the missing parts to do the pressure test and the only other thing I might be able to do is some surface prep and to spray some primer and paint on the last parts.
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