500Se tail buzz noise Need help

[Dennis P]

I am in need of some ideas.I have searched similar posts but it appears no one has really solved this issue.I have a buzz in the tail of my 500se.I have tried loosening and tightening the belt.I have balanced the tail hub seperate and then balance it with the blades.I have tried different blades.I have moved the pushrod support.Also several parts (lot's) where changed as I earlier in the summer got frustrated and started flying it with the buzz,there is no vibrations and all was working well except for the buzz! I was doing a fast backwards circuit and I heard a pop sound shortly followed by the heli tail folding up and peices starting to rain down.It appeared that the tail hub had broken and thrown a blade.I thought this would be the end of the buzz as the hub was probably faulty and was not true? Wrong I rebuilt the heli ,all runs smooth again and flys great but I have the same buzz.If I put in tail inputs the buzz changes until all comes back to relaxed.I am running 2100 rpm but it does not change really if I go up or down 100 rpm. Help as I really love the way it fly's. Thanks

[jhheli]

What esc, what mode, what batteries and how many different ones are you using.

[freakinnovice]

Have you tried a different brand of tail blades? What about lining your oneway or your belt? Any change. Have you changed out your belt?

[Dennis P]

It has a Jive 100LV in mode 4,It has had a Century 600-1100KV motor and a Scorpion 4025-1100.Battery's are Voltz 5100 35c.I am running Rotor Tech 550 mains and it has had 2 sets of Rotor Tech tail blades, one set 85mm and 1 set 92mm.It also had a set of 85 mm plastics.All with no change.I have not tried a different belt .The heli has a combined total of 12 flights from new now. Flight 7 was when it can apart mid flight.I may try a spool up with no blades tonight. What do you mean by lining my oneway? The oneway feels really good ,it holds hard and does not lock on spool down and feels very smooth. Like I mentioned earlier this heli is smooth,the fins , canopy ect are solid no vibs,mains track great.Thanks

[freakinnovice]

Sorry I meant lubing the oneway.

[gashead]

when there is a buzzing coming from the tail , i have always found it needs shimming, i use callipers to measure all the way down the gear box and use shims to keep it nice and straight.

[Dennis P]

Originally Posted by gashead

when there is a buzzing coming from the tail , i have always found it needs shimming, i use callipers to measure all the way down the gear box and use shims to keep it nice and straight.

OK the rear spacer and the idler pulley spacer are within a thou of each other.The frt is pulled in about 5 thou on the mount to hold it to the boom.You are saying that you shim the plates to the boom mount so that when you tighten the plates down to the boom they remain parallel ? I did shim the rear tail shaft until there was no play .I also glued the bearings in as the one was a drop in fit.No play but no interference fit either. Thanks

[jhheli]

You said 2100 so around 75% flat throttle, a couple of things to check would be pinion height, try some edge tail blades, also make sure the blade grips aren't rubbing the head block or touching it on one side, check the pulley inside the frame that they are push all the way back and not tilted.

Check the pin inside the tail shaft these can bend, but I want you to try something it won't hurt to just try it, now with a dead battery program mode 11 so when you spool up for the first time it should be in mode 11 with a dead battery and try a flat throttle curve of 75, what are you using to check the headspeed by the way, now use a fully charged battery and take it into a hover what is your headspeed and is it still buzzing just try it won't hurt.

[Mystic3D]

I found that if you have the carbon tail and tighten the bolts that hold it to the boom too tight, it will distort the boom and the tail case will not longer be straight.

The tail cases need to be absolutely parallel, if they are not then the bearings in the tail case will bind causing noise.
I had to replace the boom and tighten the bolts snug, not tight.

[azdan]

+1 on the tailcase. I learned this on my Logo 10.


the carbon tailbox is kind of a bugger to get right. you have to remember that the 2 carbon sides need to be parallel in order to get the tailshaft bearings running true.. most people, (including myself) tighten too much on the clamps or the tensioner and end up too tight in the front. end up with bearing wear, and or buzzing sound from the tail.

I measure the back of the tailbox with a pair of digital calipers because that where the solid bar is. then check the top front, then bottom front and bottom rear, as well as the belt tensioner. (mine goes in the front with 3 small bearings.)

Make all this the same width (same measurement all the way around the box) and you should be good and smooth with the bearings.

[Mystic3D]

Originally Posted by northcarolinadan

+1 on the tailcase. I learned this on my Logo 10.


the carbon tailbox is kind of a bugger to get right. you have to remember that the 2 carbon sides need to be parallel in order to get the tailshaft bearings running true.. most people, (including myself) tighten too much on the clamps or the tensioner and end up too tight in the front. end up with bearing wear, and or buzzing sound from the tail.

I measure the back of the tailbox with a pair of digital calipers because that where the solid bar is. then check the top front, then bottom front and bottom rear, as well as the belt tensioner. (mine goes in the front with 3 small bearings.)

Make all this the same width (same measurement all the way around the box) and you should be good and smooth with the bearings.

Nicely written process.

[azdan]

thank you !

[Dennis P]

Just an update guys.I pulled the tail apart and set it up nice and square starting with the rear spacer.I lightly snugged things all up ,measuring the width with my vernier calipers.All was nice and square and holding snug.The boom had measured fine with no deformation.I test flew it and no change.Totally frustrated I ordered all the 5003D tailbox assembly with bearings ect.I received it today and installed it all with no other changes. That is right,one happy Dude.Flew out a battery with the nice smooth sound of the electric,I did have to make some blade smack but finally to have it smooth and quite is a joy.I have no idea about the carbon tailbox but I will play with it again at a latter date as I have spent a good part of the summer fighting it already.Thanks again

[Mystic3D]

Bearings? Notchy at all for tail shaft.
Go fly, figure out later


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- Sent from my iPhone using Tapatalk

[freakinnovice]

Although maybe not the cheapest fix, I'm glad your enjoying the quiet sounds of flying a Logo. I've always flown the plastic tailbox so I've been in no rush to swap out for a carbon tail.