First thing I did was ground the tailboom and support rods to the frameset. I used enamel coated wire. I scraped the enamel off, then wrapped it twice around the screw that holds the support rod end. Used a wire brush on the dremel to clean up the surface around the bolt hole so that when the screw was tightened, the wire would have a good conduction path to the support rod. Next I removed the black coating on the tailboom just under the horizontal fin. I looped the wire up across this area and then ran it to the screw for the other support rod.

I then ran wire from the front section of the support rod to the frameset. I made sure the surface the wire touched was lightly filed to remove any non-conductive coating. The aluminum seems to have a clear coating that has some resistance. Afterwards, I checked with my Fluke 77 meter from the boom to each support rod and to left and right frames. It measured 0.1 ohm in all configurations.

I test flew it Saturday morning, but unfortunately it did not help. I could not tell it made any difference in reducing the RF problem. My next step was to check out the start shaft. I checked it with my meter and found it would vary from over 300K ohms to 125 ohms to sometimes 63 ohms if you pushed hard enough sidewasy and rotate it to just the right place. The clutch bell also showed the same intermittant conduction.

I had to think of some way to ground the bell and shaft. I did not want to use a brush against the shaft because I thought with engine vibration, this would cause intermittant contact. Grounding through the bearings is not a perfect solution, but I thought maybe if I provided more then one ground path, then using the bearings might work. I scraped the enamel coating off a short piece of wire and place both ends in the metal frame spacer holes and laid the wire down in the track for the bearing. I did this for both bearings.

I used 1400 grit sand paper with oil to remove the black coating in the bearing areas of the start shaft. The three arrows point to where the inside race of the top bearing will make contact with the staft, clutch bell bearing, and one-way bearing in the clutch.

Here you can see the wire coming out in four places to all four metal frame spacers. I re-installed everything and checked from frameset to start shaft and bell. I was no more the 3 ohms no matter what position the shaft or bell was rotated. So ground path is now from frame to engine case, through engine bearings to crankshaft to fan hub to clutch, through one way bearing in clutch to lower part of start shaft to top start shaft bearing inside race to outside race, across wire I installed to the top two metal frame spacers then back out to the frame. The clutch bell has a ground path through the inside race of the bottom bearing to the start shaft and through the top bearing to the wire I installed and to the frame spacers. In stock form, the only ground path was through the one-way clutch bearing. As long as the black coating on the bottom of the start shaft was there, then there was no conduction to the bell and start shaft. But after a little bit of runtime, the coating wears off enough to begin intermittantly contacting.

It was raining a lot today (Saturday) so I only got to run about a 1/2 tank. One thing to note is that when I usually place the starter in the start coupler, I would usually get a glitch. This has always happened on my 30's also. But now it does not do that, so I knew I had a good ground connection to the shaft. Many times I would get a glitch on the collective during spool up a little before lift off, but I did not see that anymore. I will need more flight time to determine the effectiveness of the modification I did.

1-28-1 Flew a full tank this morning experimenting with rpm and orientation. I did not get any glitchs in the air. The collective only got hit once while taking off. Another thing I noticed was that if the rpm is at 1600 and you 'bump' the cyclic stick, you get a type of wobble oscillation that settles down after a second or two. The wobble problem I had been experiencing appears to have been from the aileron and elevator getting a sudden hit and starting up this oscillation. The wobble from bumping the sticks was decreased a lot by going to 1650-1700 rpm. The wobbles from bumping the sticks has just been minor and not like the sudden big oscillations that would last as long as the helcopter had the right side facing me. Back then, I experimented with higher rpm and other orientations as well. So my RF glitching has been significantly decreased. I don't have a lot of runtime right now, but if the weather will stay dry today I will get more tanks of fuel through it. Time will tell... 1-28-1 Got 3 more full tanks at the field today. Only got one glitch and it was on the collective. Luckily everytime the collective has been hit, it always gives an up command. I finally got to have a little fun with it. I was about to see how well it would flip and hold an inverted hover, but in one of my turns one blade went out of track so I decide to take it easy. Next time I fly I will put the Model Sport blades back on. I had the woodies on it so that just in case one of the glitchs caused a crash, it wouldn't take out my expensive blades. The wood blades were very unmatched. I had corrected the spanwise cg and the weight, but the chordwise cg was too far off for me to correct. So I'm thinking this was the cause of the blade going out of track.