Plain ole everyday heli stuff

[dunkonu23]

Me, too. I'm waiting on two things to charge. My radio (I left in on all night) and a Lipo. I've swapped motors, fixed the burned out lead, and found some more chaffing. I'm hoping it's not too bad or else, I'll have to fix those leads, too.

Sorry to hear about your BH450. When I needed parts that Ka-Planes didn't have, I just searched for the part number on Google. Never had a miss.

Scott

[Jerrymac]

Hey Scott,
I know this might be a dumb question, as I know you are very thorough when you build or repair, but have you changed the head dampeners?

I once had what looked like a nasty tail vibration on one of my K2's and spent many hours trying to figure it out. Turns out the dampeners were bad and the main blades were "flapping". Since they spin so fast, I never really noticed it. I changed the dampeners and the "tail" vibration went away.

Since the tail is so long on any heli, it seems that any vibration anywhere always shows up in the tail, even if it is not the cause.

Just a thought.

[dunkonu23]

When I crashed at the Mid-America Fun Fly, I replaced them. I've got another set on order along with all the bearings, again. I'm also going to replace the head block and the center column.. along with the bearings. I'm really at a loss.

Here's a video



Scott

[Jerrymac]

I watched the vid 4 times listening to that noise, and it doesn't sound like any bearing noise I have ever heard. To me I almost sounds like the blades vibrating, I dunno. Have you tried a different set of main and tail blades to see what happens?


Jerry

[dunkonu23]

Aug 5, 2010 1:07:57 GMT -5 Jerrymac said:

I watched the vid 4 times listening to that noise, and it doesn't sound like any bearing noise I have ever heard. To me I almost sounds like the blades vibrating, I dunno. Have you tried a different set of main and tail blades to see what happens?


Jerry

It's hard to hear it in that video. What it sounds like live is a gear rubbing on a canopy. In fact, the first time I heard it, that's what I thought it was. The very low frequency sound you may hear is normal. It's the other noise I'm after. This is the third set of main blades and I don't know how may tail blades I've gone through... different sizes, brands...

Scott

[Jerrymac]

Hmmm, guess I am not hearing the noise in the vid that you are talking about. But, a gear rubbing on canopy noise , huh. Have you checked the gear mesh between ALL of the gears? Maybe one of the aluminum bearing plates got bent in the crash and the gear mesh is too tight somewhere, I dunno.

At this point, I am not sure what to suggest as it seems that you have already covered everything.

Jerry

[dunkonu23]

Thanks Jerry... but yeah.... yesterday, I put a new set of tail blades on it and the noise went away. This is the second time that happened. I fully expect the problem to return. With that in mind, yep... I've checked gears until I'm blue. So, today I've got more bearings, tail drive pulley, and dampers coming in. They, along with the swash plate are getting replaced. This is nuts. I've put about 20 cycles on one battery troubleshooting/charging. Oh, yeah... last night after my last session, I noticed the gyro foam was dry so that's getting replaced, too.

Scott

[dunkonu23]

The results of today's test...





Boom sheared off in flight.

Scott

[9sec240]

Looks like the main blades survived though.

[Jerrymac]

In flight??? Wow. Maybe it was already cracked and that was the problem, I dunno. Never seen a boom break while flying.

[dunkonu23]

I don't know what happened. It did happen about 10 seconds after lifting off. I saw it start to bend, I hit throttle hold at the same time it snapped.

Scott

[Jerrymac]

Well, my day at the field wasn't too good today. Sat there for about 2 hours waiting for a bunch of guys hitting golf balls to finish up. (They didn't seem willing to share the field ).

Flew the lil Gaui 200 first, as I am still trying to get it sorted. All seemed OK till I hit full collective to see how the tail was gonna hold and it dropped outta the sky. Motor spun up fast , but the heli dropped fast too. I think the OWB is crap as the gears were ok, and pinion not spinning on the motor shaft.

Flew the Gaui 425 next. About 1 min. into the flight, the tail started wagging back and forth pretty steady, so I decided to land and check it out. Just as I set it down, I heard a loud noise and stuff started flying off the tail.

It seems that one of the blade grip bolts came loose. The grip flew off and along with it half of the pitch slider broke off too. Not sure where all the pieces went as I couldn't find them, but I did find 11 golf balls while looking for my tail parts.

[dunkonu23]

Dang, Jerry... not a good day at all. I'm sorry to hear that. Bad weekend for Gaui Tails, too. I hope this is not the start of the "things happen in three's". Dunno. That was a very odd thing last summer.

Scott

[9sec240]

Jerry, that sucks. Sorry to hear that. Get em fixed.

[Jerrymac]

Thanks guys, I have a new gear set with OWB for the 200, so I am ok there.
I have a thrusted tail assembly and tail blades for the 425, but, I am going to have to order the tail pitch slider since I don't seem to have a spare.

I never really liked the way the Gaui thrusted tail went together though. When the bolts are tightened all the way, the grips get kind of tight. So, against my better judgement, I just put a drop of red loctite on them and did not tighten them real tight.

I guess I was lucky that it flew apart just as I set it down to check it though, or it could have been much worse. At first I thought the tail blades struck something as I set it down, but when I looked at it I could see that whole grip flew off and the bolt was not in the end of the hub. Unfortunately, one side of the pitch slider broke off where it was attached to the grip that flew off.

I will order the slider Tuesday, and should be back in the air this weekend.

[dunkonu23]

That just sucks, bro. Throwing a grip is one of my biggest fears. Thankfully nothing happened with you.

On my front... just tested the HeadHunter... still have the vibration.

Scott

[Jerrymac]

Sorry to hear that Scott. I am baffled myself, as to what might be causing it. It seems you have gone through the entire heli now with no luck.

Hopefully one of the guys at IRCHA might be able to help you figure it out.

[dunkonu23]

I made up a new set of Big Balls Bearing Mounts today. Dunno if it's gonna fix it, but at least they're new bearings.

Scott

[Jerrymac]

Well, I replaced the pitch slider and installed new blade grips and tail blades on the 425 and it flew great Sunday.
Scott and Ivan also probably saved me from a possible crash too. I remember reading somewhere ( maybe a PM ) that they found the vibration problem with Scott's HH Gaui was loose grub screws on the main gear hub. So, while checking it over I found one grub screw on my main gear missing, and the other one was loose.

One new grub screw and a couple drops of loctite and I was good to go. Thanks for that guys. I gotta start taking better care of my helis. Just can't seem to find the time. I always give them a quick pre-flight look over, but I gotta start checking them over better before going out to the field.

[dunkonu23]

Well, glad you found it, bro! It was actually the phillips head screws that hold the gear drive hub to the gear that were loose. That's what I think fixed the problem, ultimately. I can't believe the amount of time Ivan spent just looking things over. Amazing guy.

Scott