Well, that took a lot longer than it should...

There's this thing where one thing leads to another. Today was a day where one thing lead to another. It actually started last night, up until 1 am (did not know) working a problem. I barely remember how this evolved.

I finished up the Sbach.

Added a x-cross truss to absorb any torsion and fore-aft stress. This hardpoint is going to be the only thing left in a crash.

I have the engine tuned pretty well now, good idle. I am tired of not having the cowl on, and since she is touchy and needs her low needle adjusted frequently, I put a small hole in the cowl to access the low needle without thpaking the cowl off. This is a beautiful plane. I hope she settles down and let's me just fly. Never buying another Evolution Nitro Conversion.

I have mentioned this new tail wheel, but I like it so much I want to mention it again! It was one of the repairs this run.

Next I took on the gravelly RCGF 26cc that had been running fine but over the past 2 weeks has been changing and running horribly sounding. It was time to take the engine apart, to take the carb apart, and clean everything.

In breaking it down I found that the two front cylinder screws were tight, but when I replaced them they were actually stripped on the engine side. These are M4 10mm so I replaced them with 14mm M4s, to see it they would bite deeper down in the screw path, and between that and fresh threads, it worked perfectly; they felt tight going in and snuggled down nicely. While cleaning the carb, cleaning the spark of carbon (it has been running rich), I think the cylinder not being tight may have been an issue. There is some oil around the cylinder-motor box aft joint, so maybe. Either way, I ran it today and it rocks sweet now. I solved the problem, whatever it was.

In an aside, the spark is an M4F. I have no idea what that is, and wonder why it's not a CM6 like the 30cc?

All put back together.

And then this happened. The attachment to the throttle has always been an issue waiting to pop up. It snapped off. I don't like the geometry it gave, and the throttle control horn sweeps up at either end, dipping in the middle. I think it did that so that when closed it avoided the screw inn the base you see on the right. But it created a dynamic that makes the linkage challenging. I wanted to put a ball clevis on it, but they don't go on wires The standard metal ones I have are a bit long, and I have never soldered a rod or wire to a metal clevis. I had no idea if it was possible. Add to that the wire was starting to unravel handling it. It needs the wire as there is as noted so much movement at this end but for some reason really has a lot of movement at the servo. You can see in the photo I figured it out.

I found this on You Tube, and it showed you can, so I did!

So now this end of the engine is fine! I just set the needles to stock and will need to tune them. 

The servo end had its problems. The servo arm could be longer. It rotates a lot on both ends. This required me to free up the tube in the anterior wall on the right there, so it can sweep back and forth. I then had problems with the set screw on the control horn not releasing, and had to pull everything, and yank it off. Now I needed another one of those wire linkages for the control horn. I found one that works. I have to use this and I don't have a longer control horn that fits the servo and the control horn linkage. I had to figure this out. In the end it works well. But in rotation at the high throttle end it pulled the servo forward and bent the deck. I had to put a cross piece to strengthen the floor, and in the end was able to set the endpoints to not require so much rotation. I also had to shave the motor mount next to the clevis as the wire aft end of the clevis would catch on it and click over it. Shaving it off with the Dremel solved that. I finally took her outside and ran her up. Tough getting her to start, but she did and runs wonderfully. I was setting the endpoints and tuning the low end for idle, and the battery died. Swapped it out. A few runs later the power switch failed on, the electrical ignition cut out would not stop the ignition, and she wasn't responding to the throttle running WOT! I pulled the battery connection and stopped it. Testing showed the switch failed on. What I don't understand is why the electronic ignition kill didn't work and why she stopped responding to the throttle.

I have a computerized switch I replaced the simple slide switch out. That sunnovabitch didn't want to come out. That took an hour. I created a hard plate of plywood to put the push run-off switch to storage the force of turning it on and off. All fixed. The interesting thing is I was looking for fail-on switch, and they are hard to find, and not cheap. Harder still  was finding a magnetic one. I have a couple of these computerized switches on planes and they are great, but bulky and require a firm surface. That took an hour.

During fueling I saw gas spraying out of the unused hole (it has a two pipe system, vent and combo fill-engine line) on the tank stopper... I made a piece of pipe filled with solder and pulled the tank, shoved that in there. Problem solved, but that took an hour.

Finally all done. It was past 7 pm, a little late to be running the engine, so fine tuning the low end will have to wait.

Whew. And to think the wx was so nice I could have been flying. When I have a plane with a problem though, I have to focus on that, so that's what I did, and why last night I suddenly realized how late it was.