Set backs seem like the usual in airplane projects, and yesterday was a day of setbacks. Greg, Nate, and I each were working on things that are going to require repair, rework, and more fiddling.
Greg and I were working on the baffle seal. We are trying to get the baffle seal material to lay down against the cowl nicely without puckering so that it doesn’t allow precious cooling air out the cowl without going through the engine cooling fins first. We made progress in some areas, but regressed at the top center. That area has major gaps now and we will have to cut that section of baffle seal out and re-do it. We will get it… Eventually
Nate got the thermotech aluminum heat barrier on the wing roots to protect the fiberglass. It is amazing how sticky that stuff is. It will take serious work if it ever needs to come off. We just need to RTV the seams and put the hardware back in.
I was able to make a few parts for the rudder actuation. I got the push tubes done, and a good start on the rudder pivot stud and rudder stop. Hopefully I get those done today.
The biggest set back from yesterday was in regards to aileron balance. We went and got a scale to see how much weight we would have to use to get the ailerons to balance. 2.5 pounds. That is a lot. Nate spent a lot of time working on sanding off as much finishing material as he could. It had to help, but the difference was negligible.
Then we tried digging a trough in back of the balance weight to add lead. We couldn’t even get two lbs of lead in there and it wasn’t enough to balance it. We realize you want the weight as far forward as possible but figured that trough may be easier than the next step.
We then got to thinking, and decided to measure my aileron. The aileron is not the right size. It is about 3/16″ off at the leading edge. That puts the balance weight closer to the hinge line than designed, not helping our situation. So we bit the bullet and sliced off the balance weight. But the question is how much weight do we need to bond back on in the right place to get the aileron to balance. The plans use a 3/8 steel rod, I’ve heard most people use a 7/16″ rod (this is apparently a common problem), and I have been told it is acceptable to use a 1/2″ rod.
So we rigged up a little jig to see if we could figure out what we needed. We should be able to calculate this, but by this time it was nearly midnight, and my math ability had gone to bed. So we used popsicle sticks to jig the weight in the proper position relative to the hinge line. (You can really see how far off I was when we built the ailerons.) Then we hung the aileron and it still doesn’t balance. So we started adding weight to see how much we needed at the new location. We are now down to needing to add 1.5 lbs. Still seems like a lot, but much better. If we use the 1/2″ steel rod, that adds 1.4 lbs. So we are going to start there.
Where did you source your spark plug wire grommets?
Aircraft spruce.