300X - the HOW TO GET RID OF VIBRATIONS tread

[nartac]

Originally Posted by Nelsonisms

Also has anyone else seen this issue with fitting the carbon fiber tail blades in the TRex tail hub assembly. Since they're just collecting dust now, I thought I might try to file down the root a bit to see if I can get them to clear the bolt.

I have just installed a Tarot thrust bearing tail grips for a buddy with cf tail blades and had the same issue. I had to file down the end a bit so that it won't bind to the screw that holds the grip to the hub then balance out the blades afterwards. Seems to work fine.

I also have to do the same with Blade orange tail blades on my Tarot thrust bearing tail grips as well. I have read that people who purchased the Lynx tail blades don't have this problem but I have not tried the Lynx tail blades to confirm.

[Stubbz]

Just flew mine in some pretty high winds for first time since I changed the main shaft n FS redid the pitch setup on the BX, for some reason I all of a sudden had to reverse my pitch in my TX to get it to fly but everything was fine and I haven't been in reversing to change it at all so idk what happened there, at first it wouldn't lift so I hit TH and lowerd pitch and it popped off the ground, came in double checked everything and reversed pitch and then it flew fine for a pack.

I do have some pretty good vibration goin on during spool up in normal mode and it even sounds at first like the main shaft is moving side to side, once up to speed its smooth but during take off to hover I did see the canopy shaking, flies perfectly fine tho, no roll or anything like that and im at 80% throttle with carbon blades. Maybe belt is just a touch loose but when I tried to tighten it to the book spec it caused a lot of drag and stopped the main very fast. Is that normal? Overall seemed to fly great for the 15-20mph gusts outside right now.

After the flight I looked at the main and tried to move it by hand and it does seem to move forward and backward but not side to side, guess it could be the bearings in the frame or the frame itself.

[SHYguy]

@nartac: Lynx tail blades touch slightly. You don't have to file off material but it doesn't hurt to do so.

@Stubbz: You probably flipped your main grips but mounted the main blades correctly. Trailing vs leading. Been there done that

[Stubbz]

They should be trailing then? I'm sure I did cuz I looked at all my other helis and they were all leading

[KiloXray]

Originally Posted by Stubbz

They should be trailing then? I'm sure I did cuz I looked at all my other helis and they were all leading

Yep, they should be trailing. The 450x and 300x are both trailing.

[65L88]

Originally Posted by KiloXray

Yep, they should be trailing. The 450x and 300x are both trailing.

At least that's the way Blade designed these two helis. I changed mine to leading edge control first thing for the simple reason that all my other helis are leading edge. It just doesn't seem right to me to see the swash drop as positive collective is applied....

[KiloXray]

Originally Posted by 65L88

At least that's the way Blade designed these two helis. I changed mine to leading edge control first thing for the simple reason that all my other helis are leading edge. It just doesn't seem right to me to see the swash drop as positive collective is applied....

LOL. Makes perfect sense to me. Stick goes down, swash goes down. Stick goes up, swash goes up. Then again, I only really know the 300x and 450x, so of course it looks "right" to me.

[Stubbz]

yeah looked opposite to me as well. It doesn't cause any other vibes or nothing right so I really can just leave it the way I have it now I guess?

[65L88]

Originally Posted by Stubbz

yeah looked opposite to me as well. It doesn't cause any other vibes or nothing right so I really can just leave it the way I have it now I guess?

I would leave it like it is. I assume you have alloy grips, otherwise the capscrews that hold the blades have to be inserted from the bottom? Makes no difference really, as the nuts are nyloc and should stay put...

[Stubbz]

full metal head yeah, swash, grips, hub. I'll leave it like it is.

[65L88]

Originally Posted by Stubbz

full metal head yeah, swash, grips, hub. I'll leave it like it is.

[Nelsonisms]

Originally Posted by nartac

I have just installed a Tarot thrust bearing tail grips for a buddy with cf tail blades and had the same issue. I had to file down the end a bit so that it won't bind to the screw that holds the grip to the hub then balance out the blades afterwards. Seems to work fine.

I also have to do the same with Blade orange tail blades on my Tarot thrust bearing tail grips as well. I have read that people who purchased the Lynx tail blades don't have this problem but I have not tried the Lynx tail blades to confirm.

Thanks for confirming that about the carbon blades. I think I will try to file them down if in doing so I don't weaken them too much. I just hate to waste money on parts that don't get used. I'm definitely bummed I won't be able to use those aluminum tail grips. But if they tend to make my helicopter shake like a wet dog and crash then so be it.

[nartac]

Originally Posted by Nelsonisms

Thanks for confirming that about the carbon blades. I think I will try to file them down if in doing so I don't weaken them too much. I just hate to waste money on parts that don't get used. I'm definitely bummed I won't be able to use those aluminum tail grips. But if they tend to make my helicopter shake like a wet dog and crash then so be it.

np, buddy. Actually, I only have to file just a tad, enough to clear the mentioned bolt then balance out the blades. I don't think the amount of material taken off compromised with the strength at all. My buddy, dragon79, is flying it and has no shake or wag whatsoever. He seems to be happy with it.

[Stubbz]

Blade aluminum tail grips on mine with im sure a few crashes, 1 i know of personally but tail stays locked and it flies fine even with beat tail blades. Little vibe on spool up but no roll or anything once into the air, I think the right roll is a lot easier to get with the beastx up top hanging off the frame vs under where it belongs even if it is a pain in the neck to adjust and see.

[dragon79]

Originally Posted by nartac

np, buddy. Actually, I only have to file just a tad, enough to clear the mentioned bolt then balance out the blades. I don't think the amount of material taken off compromised with the strength at all. My buddy, dragon79, is flying it and has no shake or wag whatsoever. He seems to be happy with it.

Yep I can vow for that. It's amazing what a part can do, and the 300x is a happier heli now. no shakes, or wags as mentioned.

[Nelsonisms]

Originally Posted by Stubbz

Blade aluminum tail grips on mine with im sure a few crashes, 1 i know of personally but tail stays locked and it flies fine even with beat tail blades. Little vibe on spool up but no roll or anything once into the air, I think the right roll is a lot easier to get with the beastx up top hanging off the frame vs under where it belongs even if it is a pain in the neck to adjust and see.

All I know is that with those grips installed the amount of vibration on my heli would be a problem regardless of where the Beast is mounted. I mean so much so that my hand was numb after holding for heli for a few seconds. You could visibly see the tail fin blurring out. I'd say the vibrations with the T-Rex assembly are less than 1/4 what they are with the Blade aluminum hub/aluminum grips installed. So I'm not exaggerating when I say they are crazy vibes.

I'm not giving up yet. Maybe the light bulb will go on and I'll realize something I hadn't before. But this isn't exactly rocket science, so I'm not holding out a whole lot of hope for that. Do you know what head speed you are running? That would be an interesting data point to consider.

[Stubbz]

Originally Posted by Nelsonisms

I'm not giving up yet. Maybe the light bulb will go on and I'll realize something I hadn't before. But this isn't exactly rocket science, so I'm not holding out a whole lot of hope for that. Do you know what head speed you are running? That would be an interesting data point to consider.

Mine is stock motor and pinion at 90% throttle so not sure what thatd be for headspeed. After my mishap then new servo gears, main shaft, n FS i flew one pack yesterday and it had a lot of vibration building spool up and smoothed out a bit once about to lift off but soon as it did i could see the whole canopy shaking a bit but didnt get any wierd effects of wanting to roll or anything. I just think having the beastx hanging off the frame cant help to reduce the vibration for it.

[SHYguy]

Originally Posted by Nelsonisms

All I know is that with those grips installed the amount of vibration on my heli would be a problem regardless of where the Beast is mounted. I mean so much so that my hand was numb after holding for heli for a few seconds. You could visibly see the tail fin blurring out. I'd say the vibrations with the T-Rex assembly are less than 1/4 what they are with the Blade aluminum hub/aluminum grips installed. So I'm not exaggerating when I say they are crazy vibes.

I'm not giving up yet. Maybe the light bulb will go on and I'll realize something I hadn't before. But this isn't exactly rocket science, so I'm not holding out a whole lot of hope for that. Do you know what head speed you are running? That would be an interesting data point to consider.

2 things:

Swap out the hub with an Align or Tarot, the stock one is super soft and bends very easily.

Shim away all play, then balance the whole tail unit.

[Nelsonisms]

Originally Posted by SHYguy

2 things:

Swap out the hub with an Align or Tarot, the stock one is super soft and bends very easily.

Shim away all play, then balance the whole tail unit.

I appreciate the insight, but I thought I was clear that I was comparing it to the T-Rex (Align) assembly which I've been using for many months. I just threw on the Blade brand aluminum grips this weekend to test them out with the Blade brand carbon fiber tail blades (because they didn't fit in the T-Rex grips) and ran into these crazy vibes. So I put the T-Rex (Align) hub/grips with Lynx plastic tail blades back on and it's back like it was. I stated in my previous post that I did place the whole assembly on a prop balancer and it was pretty much dead even. So it's a mystery to me. I just wonder if the people these are working for aren't simply running a much lower head speed which is simply keeping the vibrations under a dangerous threshold. Either that, or like you said, it's some play in the grips that is causing it. I suppose there is possibly a little bit of play, but not much. They are brand new grips and a brand new hub. I'll try shimming it out entirely and see if that makes a difference. It's really more of a curiosity thing for me at this point and I'll probably stick with the T-Rex (Align) grips because they've been pretty much flawless. I'm just bummed because I've got two tiny new bling paper weights. In contrast, the Blade brand aluminum tail grips on my 450X have none of these issues.

[SHYguy]

OK, I see. But keep in mind that the Blade alu tail hub can actually come pre-bent! It's ridicilously soft.

Sorry if I've missed it - but have you tried?
-Align or Tarot hub
-Blade alu grips
-Blade carbon tail blades

TBH I don't remember at the moment if I'm using the Align or Tarot hub, but it has a step so it's spacing the alu grips out a bit. I think it's Tarot?

Ways to check for a bent hub:

[ame]http://youtu.be/Sxh_JHJjQQM[/ame]

[ame]http://youtu.be/ICZFg-HzTW8[/ame]

As to balancing you can also try dynamic balancing (trial and error)