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semperfib400 · 03-31-2015, 12:35 PM

So after I recent crash I had I had to replace some bent items obviously. I have just replaced the blade grips as I thought this would cure my "wobble" I was getting. One of the grips was tracking higher than the other. Replacing the grips did not fix this.

Feathering shaft and main shaft are all perfectly straight.

I'm curious if I maybe bent the main head block that bolts on to the main shaft? Is that even possible?

weav01 · 03-31-2015, 06:02 PM

Definately a possibility. Time to buy a spare to troubleshoot with

Boinker · 03-31-2015, 10:32 PM

If you have not replaced the main and spindle replace them anyhow. But just to check them go ahead and do this.

Yank the head off and tail blades, spool up the help a little and look straight down at the main shaft. If it moves at all there is your problem.

Take one hex wrench and turn one of the screws connected to the spindle shaft. If anything moves up or down then you have a bent spindle. If it does not then either your head block is out or your blades are missbalanced.

Justmy two cents but if you went in hard enough to bend that head block there will be Alot more casualties then just it.

RC/DC_5000 · 04-01-2015, 05:40 PM

It is possible to bend the main rotor housing!! I know exactly how you feel... about a year ago I had a bad crash.. replaced everything but the rotor housing.. because I thought, how could that possibly bend?

It can.

But I'd also replace the MS and FS. Those are standard replacements for every crash of mine. I don't even try to salvage those. You will be haunted with ghost vibrations.

alyon187 · 05-19-2015, 10:38 AM

I have the same issue, any chance you fixed this?

semperfib400 · 05-19-2015, 10:41 AM

I ended up replacing the main blade grips and it went away. Something got bent when I had my original crash.

alyon187 · 05-19-2015, 11:20 AM

Ive tried everything, the whole head is new and still no avail

semperfib400 · 05-19-2015, 11:23 AM

what head speeds are you running?

I'm running gov'ed headspeeds and that helps too.

Does your TT have any signs of rubbing on the side at all? Mine had that also and I re-did the baring placement and placed it EXACTLY as described in the manual and that helped too. Before this I tried multiple bearings and that didn't help either.

Also make sure you boom is not pushed in quite as hard... push it in all the way and then back it off just a bit.

alyon187 · 05-19-2015, 11:35 AM

No sure on hs, I'm running tc. Ive tried high/lower hs. More gain/less gain. I can set up the head good and all checks out but when I spin the head by hand and check blades I can tell they are spinning on different planes but I have same pitch on both blades and level swash at all ranges. I am running two bearings on the tt and the rod is new as are yhe bearings.

semperfib400 · 05-19-2015, 12:37 PM

It's hard to tell by hand. Try spinning up the head a little without the main blades and see if you notice the grips spinning in the same plane. With mine I had one of the grips that was way off.

alyon187 · 05-19-2015, 12:49 PM

Yah but I put a ruler close to the place they pass and I can measure the difference of 2 or 3 cm

alyon187 · 05-19-2015, 12:55 PM

The only thing I can think of that will cause this is that somehow the dampers are not the same. One could be different than the other causing the fs to angle down. Cuz the fs, dampers as well as the main are new.

semperfib400 · 05-19-2015, 01:01 PM

Can you post a youtube video of the vibrations?

alyon187 · 05-19-2015, 01:56 PM

If you looks down the 450 pro section ive got some vib logs on there

alyon187 · 05-19-2015, 01:56 PM

I mean the vbar section

CrashNburn420 · 05-19-2015, 02:12 PM

Try this, take the blades off, power it up and set zero pitch. Put a Allen wrench through the bolt hole on the blade grip. It should be parallel with the main shaft. Spin the head around and check it in that same spot with the other grip. It sounds like one of the dfc links is a little longer from the swash to the grip.

Are you using a swash leveler? Or eye balling it?

alyon187 · 05-19-2015, 02:17 PM

That's exactly the way I set mine up. After I do it this way, I put the blades on and fold them back and they are level. But when Iunfold them and spin the head and check the spot the pass, w a ruler, they are on different planes. About 2 or 3 cm difference

alyon187 · 05-19-2015, 02:21 PM

Dfc links look to be the same length.

When I check to make sure they are parallel w boom, one is parallel while the other is at a higher position, not parallel

CrashNburn420 · 05-19-2015, 02:23 PM

How does it fly?

alyon187 · 05-19-2015, 03:14 PM

Bobbles, high vibs, shakes on skids sometimes on spool up/down

03-31-2015, 12:35 PM	#1 (permalink)
semperfib400 Registered Users Join Date: May 2011	450L Head Wobble So after I recent crash I had I had to replace some bent items obviously. I have just replaced the blade grips as I thought this would cure my "wobble" I was getting. One of the grips was tracking higher than the other. Replacing the grips did not fix this. Feathering shaft and main shaft are all perfectly straight. I'm curious if I maybe bent the main head block that bolts on to the main shaft? Is that even possible? __________________ 500 PRO DFC IKON Flybarless HW RPM Sensor RC Airplane Build Logs

03-31-2015, 06:02 PM	#2 (permalink)
weav01 Registered Users Join Date: Jul 2012 Location: Virginia Beach	450L Head Wobble Definately a possibility. Time to buy a spare to troubleshoot with

05-19-2015, 10:38 AM	#5 (permalink)
alyon187 Registered Users Join Date: Feb 2015	I have the same issue, any chance you fixed this? __________________ Goblin 380 (Spirit), X3 (VBAR), DX9 (I.Y.A.O.Y.A.S.)

05-19-2015, 10:41 AM	#6 (permalink)
semperfib400 Registered Users Thread Starter Join Date: May 2011	I ended up replacing the main blade grips and it went away. Something got bent when I had my original crash. __________________ 500 PRO DFC IKON Flybarless HW RPM Sensor RC Airplane Build Logs

05-19-2015, 11:20 AM	#7 (permalink)
alyon187 Registered Users Join Date: Feb 2015	Ive tried everything, the whole head is new and still no avail __________________ Goblin 380 (Spirit), X3 (VBAR), DX9 (I.Y.A.O.Y.A.S.)

03-31-2015, 10:32 PM	#3 (permalink)
Boinker Registered Users Join Date: Jan 2013	If you have not replaced the main and spindle replace them anyhow. But just to check them go ahead and do this. Yank the head off and tail blades, spool up the help a little and look straight down at the main shaft. If it moves at all there is your problem. Take one hex wrench and turn one of the screws connected to the spindle shaft. If anything moves up or down then you have a bent spindle. If it does not then either your head block is out or your blades are missbalanced. Justmy two cents but if you went in hard enough to bend that head block there will be Alot more casualties then just it.

04-01-2015, 05:40 PM	#4 (permalink)
RC/DC_5000 Registered Users Join Date: Jan 2015	It is possible to bend the main rotor housing!! I know exactly how you feel... about a year ago I had a bad crash.. replaced everything but the rotor housing.. because I thought, how could that possibly bend? It can. But I'd also replace the MS and FS. Those are standard replacements for every crash of mine. I don't even try to salvage those. You will be haunted with ghost vibrations.

05-19-2015, 11:23 AM	#8 (permalink)
semperfib400 Registered Users Thread Starter Join Date: May 2011	what head speeds are you running? I'm running gov'ed headspeeds and that helps too. Does your TT have any signs of rubbing on the side at all? Mine had that also and I re-did the baring placement and placed it EXACTLY as described in the manual and that helped too. Before this I tried multiple bearings and that didn't help either. Also make sure you boom is not pushed in quite as hard... push it in all the way and then back it off just a bit. __________________ 500 PRO DFC IKON Flybarless HW RPM Sensor RC Airplane Build Logs

05-19-2015, 11:35 AM	#9 (permalink)
alyon187 Registered Users Join Date: Feb 2015	No sure on hs, I'm running tc. Ive tried high/lower hs. More gain/less gain. I can set up the head good and all checks out but when I spin the head by hand and check blades I can tell they are spinning on different planes but I have same pitch on both blades and level swash at all ranges. I am running two bearings on the tt and the rod is new as are yhe bearings. __________________ Goblin 380 (Spirit), X3 (VBAR), DX9 (I.Y.A.O.Y.A.S.)

05-19-2015, 12:37 PM	#10 (permalink)
semperfib400 Registered Users Thread Starter Join Date: May 2011	It's hard to tell by hand. Try spinning up the head a little without the main blades and see if you notice the grips spinning in the same plane. With mine I had one of the grips that was way off. __________________ 500 PRO DFC IKON Flybarless HW RPM Sensor RC Airplane Build Logs

05-19-2015, 12:49 PM	#11 (permalink)
alyon187 Registered Users Join Date: Feb 2015	Yah but I put a ruler close to the place they pass and I can measure the difference of 2 or 3 cm __________________ Goblin 380 (Spirit), X3 (VBAR), DX9 (I.Y.A.O.Y.A.S.)

05-19-2015, 12:55 PM	#12 (permalink)
alyon187 Registered Users Join Date: Feb 2015	The only thing I can think of that will cause this is that somehow the dampers are not the same. One could be different than the other causing the fs to angle down. Cuz the fs, dampers as well as the main are new. __________________ Goblin 380 (Spirit), X3 (VBAR), DX9 (I.Y.A.O.Y.A.S.)

05-19-2015, 01:01 PM	#13 (permalink)
semperfib400 Registered Users Thread Starter Join Date: May 2011	Can you post a youtube video of the vibrations? __________________ 500 PRO DFC IKON Flybarless HW RPM Sensor RC Airplane Build Logs

05-19-2015, 01:56 PM	#14 (permalink)
alyon187 Registered Users Join Date: Feb 2015	If you looks down the 450 pro section ive got some vib logs on there __________________ Goblin 380 (Spirit), X3 (VBAR), DX9 (I.Y.A.O.Y.A.S.)

05-19-2015, 01:56 PM	#15 (permalink)
alyon187 Registered Users Join Date: Feb 2015	I mean the vbar section __________________ Goblin 380 (Spirit), X3 (VBAR), DX9 (I.Y.A.O.Y.A.S.)

05-19-2015, 02:12 PM	#16 (permalink)
CrashNburn420 Registered Users Join Date: May 2012	450L Head Wobble Try this, take the blades off, power it up and set zero pitch. Put a Allen wrench through the bolt hole on the blade grip. It should be parallel with the main shaft. Spin the head around and check it in that same spot with the other grip. It sounds like one of the dfc links is a little longer from the swash to the grip. Are you using a swash leveler? Or eye balling it?

05-19-2015, 02:17 PM	#17 (permalink)
alyon187 Registered Users Join Date: Feb 2015	That's exactly the way I set mine up. After I do it this way, I put the blades on and fold them back and they are level. But when Iunfold them and spin the head and check the spot the pass, w a ruler, they are on different planes. About 2 or 3 cm difference __________________ Goblin 380 (Spirit), X3 (VBAR), DX9 (I.Y.A.O.Y.A.S.)

05-19-2015, 02:21 PM	#18 (permalink)
alyon187 Registered Users Join Date: Feb 2015	Dfc links look to be the same length. When I check to make sure they are parallel w boom, one is parallel while the other is at a higher position, not parallel __________________ Goblin 380 (Spirit), X3 (VBAR), DX9 (I.Y.A.O.Y.A.S.)

05-19-2015, 02:23 PM	#19 (permalink)
CrashNburn420 Registered Users Join Date: May 2012	How does it fly?

05-19-2015, 03:14 PM	#20 (permalink)
alyon187 Registered Users Join Date: Feb 2015	Bobbles, high vibs, shakes on skids sometimes on spool up/down __________________ Goblin 380 (Spirit), X3 (VBAR), DX9 (I.Y.A.O.Y.A.S.)

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