Feathering shaft bolt head in the way!

phred · 10-08-2008, 08:15 AM

Hi,
I have just purchased myself a second hand B400 PNP and am trying to get my head around this, as it's my first heli.

Anyway one of the (many) problems I've encountered is that I had two sets of Eflite blades with the heli that were stuffed. Not wanting to be unsafe I decided to buy a new pair. So my LHS guy sold me a pair of Align 325 Pro blades for the T450, and he said they fit fine. They don't - need some shims or washers to make up for the thickness of the originals. Of course the head honcho a the LHS had never heard of that before.

Anyway, when I tried to fit the Align blades one fitted ok (with shims - made from cut up credit card! hope that works and their irregular shape won't cause vibrations with different weights?).
The other blade wouldn't fit because when I inserted it the head end of the blade butted up against the screw/bolt that holds the feathering shaft together or in place (Bolt nr 28 on the exploded diagram). Weird thing is that the one on the other side is ok. It's in far enough for the blade to fit.
I watched 'Helimix's' feathering shaft repair video in full (thanks Helimix

very helpful) and removed the feathering shaft (found two o rings were worn - replaced them) and put it all back together again but still same problem.

Has anyone had a similar problem to this that can assist me with solving this?
I'm really stuck here and the LHS guys are proving to be unhelpful.

Any help gratefully appreciated.

Thanks.

Swashmix · 10-08-2008, 08:23 AM

Those bolts must go in to the shaft and tighten up equally on both sides. I have tried most makes of the 325mm blades and they all fit. You should have about 1-2 mm of clearance between the bolt head and the blade. That bolt has to go in farther.

Do you have the correct length of bolts for the feathering shaft?

Dazz · 10-08-2008, 08:34 AM

Check the bible for the exploded feathering shaft view ( sticky at the top of the page )

Take it apart and rebuild carefuly ensuring the order is correct ......it sounds to me like something is not sat right .....possibly a bearing in the blade holder

phred · 10-08-2008, 08:46 AM

Thanks for the quick reply's really great stuff.

Yes I'll take it apart again. The bloke that sold it to me assures me it's only been flown twice and never maintained! Well I found one of the thrust bearing washers inserted the wrong way.

Also it appears to be missing grub screws from where the flybar runs through the flybar cage, but the diagram has no numbering for those grub screws, and the spare parts i got withe the heli the grub screws are twice the size requried.
My quested also is can the heli be flown without those screws?

Thanks.

phred · 10-08-2008, 08:47 AM

Doering as far as I can tell the bolts are the right length. Maybe this person has put the wrong ones in. Bad mistake buying a second hand heli like this - I've dudded myself i think.
Guess I'll learn the hard way

Slyster · 10-08-2008, 08:53 AM

This is a good pic

Swashmix · 10-08-2008, 08:55 AM

Quote:

Originally Posted by phred

My quested also is can the heli be flown without those screws?

Thanks.

That flybar has to be locked down in place and even on both sides. If your LHS carries parts hopefully you can buy the part (bag) with the complete screw set. I'm pretty sure it has the set screws too.

bladelearnin · 10-08-2008, 09:35 AM

Quote:

Originally Posted by phred

Hi,
I have just purchased myself a second hand B400 PNP and am trying to get my head around this, as it's my first heli.

Anyway one of the (many) problems I've encountered is that I had two sets of Eflite blades with the heli that were stuffed. Not wanting to be unsafe I decided to buy a new pair. So my LHS guy sold me a pair of Align 325 Pro blades for the T450, and he said they fit fine. They don't - need some shims or washers to make up for the thickness of the originals. Of course the head honcho a the LHS had never heard of that before.

Anyway, when I tried to fit the Align blades one fitted ok (with shims - made from cut up credit card! hope that works and their irregular shape won't cause vibrations with different weights?).
The other blade wouldn't fit because when I inserted it the head end of the blade butted up against the screw/bolt that holds the feathering shaft together or in place (Bolt nr 28 on the exploded diagram). Weird thing is that the one on the other side is ok. It's in far enough for the blade to fit.
I watched 'Helimix's' feathering shaft repair video in full (thanks Helimix

very helpful) and removed the feathering shaft (found two o rings were worn - replaced them) and put it all back together again but still same problem.

Has anyone had a similar problem to this that can assist me with solving this?
I'm really stuck here and the LHS guys are proving to be unhelpful.

Any help gratefully appreciated.

Thanks.

best thing to use for shime is the root(black plastic of the old eflite blades work perfect just cut little washers out of them but on your feathering shaft prob never encountered that one sorry

phred · 10-08-2008, 09:38 AM

Hmmn,
Well now I'm a little more confused. Because having just taken it apart again (wish I had a decent digital camera to post a pic).
There are 3 shims on one side and 4 on the other. I'm sure the video showed something similar too. Your diagram shows only possibly two? Cant see the thickness of two shims causing the problem.
I just replaced the feathering shaft as it appeared to be ever so slightly bent very tiny.

Guess I'll just keep pulling it apart and putting it back together until i can do it in my sleep then - I dunno. Need to think about this.
Guess another trip to the LHS is in order.

Thanks anyway for the assist - really helps.

bladelearnin · 10-08-2008, 09:44 AM

Quote:

Originally Posted by phred

Hmmn,
Well now I'm a little more confused. Because having just taken it apart again (wish I had a decent digital camera to post a pic).
There are 3 shims on one side and 4 on the other. I'm sure the video showed something similar too. Your diagram shows only possibly two? Cant see the thickness of two shims causing the problem.
I just replaced the feathering shaft as it appeared to be ever so slightly bent very tiny.

Guess I'll just keep pulling it apart and putting it back together until i can do it in my sleep then - I dunno. Need to think about this.
Guess another trip to the LHS is in order.

Thanks anyway for the assist - really helps.

Phred you need to have equal shims on both sides some use 2 for less responsive cyclic and some use more the more you use the more twitchy to control and ifyour a noobee like me you want it a little tamer the shims that you buy are for teh cp pro same ones hope this helps John

phred · 10-08-2008, 10:44 AM

Ok John,
Thanks thats noted. I think I'll remove some and leave two on each side. The tamer the better for me.
I did just find this website handy http://www.repairblade400.com/#featheringshaft
where they lay out the components. What appears wrong on mine is that next to the O ring is no step down washer... this person had it at the other end near the inner end of the blade grip - go figure...
Thanks. :o)

LockMD · 10-08-2008, 10:52 AM

Quote:

Originally Posted by phred

What appears wrong on mine is that next to the O ring is no step down washer... this person had it at the other end near the inner end of the blade grip - go figure...
Thanks. :o)

that is the correct spot step washer rides on bearing. and shims are inbetween the step and O-ring.

RVFR · 10-08-2008, 02:30 PM

Was going to throw it out there as maybe it's the wrong shaft, I've heard, correct me if I'm wrong, that the 450 trex shaft will also work, but is a bit longer so???? but now that you went and put in a new one, are you still having the same problem?

xspare · 10-08-2008, 02:51 PM

Quote:

Originally Posted by bladelearnin

Phred you need to have equal shims on both sides some use 2 for less responsive cyclic and some use more the more you use the more twitchy to control and ifyour a noobee like me you want it a little tamer the shims that you buy are for teh cp pro same ones hope this helps John

My RTF showed up with 4 shims on each side and seemed to be fine. On a recent rebuild I dropped a shim on the carpet. Being too lazy to reassemble the flybar, I've been flying with 4 shims on one side and 3 on the other and didn't reallly notice any difference.

Quote:

Originally Posted by doering1

That flybar has to be locked down in place and even on both sides. If your LHS carries parts hopefully you can buy the part (bag) with the complete screw set. I'm pretty sure it has the set screws too.

My RTF showed up with two set screws (grub screws?) on the flybar, one on each side, which seems to be production change related to a 5 cent cost reduction... Can't say it's been a problem for me.

neilg. · 10-08-2008, 05:47 PM

if you use the 325mm blades from align you only have to shim the blade grip. maybe the race is not seated properly?

if you use the align feathering shaft, it goes like this:

cap screw, washer, xtra race, race, cage, race, shim, bearing

works for me

a little sanding of the align blade will keep capscrew from rubbing against it.

10-08-2008, 08:15 AM	#1
phred Registered Users My HF Map location Join Date: Sep 2007 Location: Perth, West Australia	Feathering shaft bolt head in the way! Hi, I have just purchased myself a second hand B400 PNP and am trying to get my head around this, as it's my first heli. Anyway one of the (many) problems I've encountered is that I had two sets of Eflite blades with the heli that were stuffed. Not wanting to be unsafe I decided to buy a new pair. So my LHS guy sold me a pair of Align 325 Pro blades for the T450, and he said they fit fine. They don't - need some shims or washers to make up for the thickness of the originals. Of course the head honcho a the LHS had never heard of that before. Anyway, when I tried to fit the Align blades one fitted ok (with shims - made from cut up credit card! hope that works and their irregular shape won't cause vibrations with different weights?). The other blade wouldn't fit because when I inserted it the head end of the blade butted up against the screw/bolt that holds the feathering shaft together or in place (Bolt nr 28 on the exploded diagram). Weird thing is that the one on the other side is ok. It's in far enough for the blade to fit. I watched 'Helimix's' feathering shaft repair video in full (thanks Helimix very helpful) and removed the feathering shaft (found two o rings were worn - replaced them) and put it all back together again but still same problem. Has anyone had a similar problem to this that can assist me with solving this? I'm really stuck here and the LHS guys are proving to be unhelpful. Any help gratefully appreciated. Thanks.

10-08-2008, 08:53 AM	#6
Slyster Registered Users My HF Map location Join Date: May 2008 Location: Maplewood, MN	This is a good pic __________________ It's not just a hobby... it's a lifestyle! Outrage Fusion & 550 / Goblin 700 / SK540 / Kontronik / DX8 / Quantum / RJX / 4010 Duo Pete Team Outrage.

10-08-2008, 02:30 PM	#13
RVFR Registered Users Join Date: Sep 2008	Was going to throw it out there as maybe it's the wrong shaft, I've heard, correct me if I'm wrong, that the 450 trex shaft will also work, but is a bit longer so???? but now that you went and put in a new one, are you still having the same problem? __________________ The best way to get around To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

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10-08-2008, 08:23 AM	#2
Swashmix Registered Users My HF Map location Join Date: May 2008 Location: Dundas, Ontario, Canada	Those bolts must go in to the shaft and tighten up equally on both sides. I have tried most makes of the 325mm blades and they all fit. You should have about 1-2 mm of clearance between the bolt head and the blade. That bolt has to go in farther. Do you have the correct length of bolts for the feathering shaft?

10-08-2008, 08:34 AM	#3
Dazz Registered Users Join Date: Aug 2008 Location: Rotherham south yorks UK	Check the bible for the exploded feathering shaft view ( sticky at the top of the page ) Take it apart and rebuild carefuly ensuring the order is correct ......it sounds to me like something is not sat right .....possibly a bearing in the blade holder

10-08-2008, 08:46 AM	#4
phred Registered Users Thread Starter My HF Map location Join Date: Sep 2007 Location: Perth, West Australia	Thanks for the quick reply's really great stuff. Yes I'll take it apart again. The bloke that sold it to me assures me it's only been flown twice and never maintained! Well I found one of the thrust bearing washers inserted the wrong way. Also it appears to be missing grub screws from where the flybar runs through the flybar cage, but the diagram has no numbering for those grub screws, and the spare parts i got withe the heli the grub screws are twice the size requried. My quested also is can the heli be flown without those screws? Thanks.

10-08-2008, 08:47 AM	#5
phred Registered Users Thread Starter My HF Map location Join Date: Sep 2007 Location: Perth, West Australia	Doering as far as I can tell the bolts are the right length. Maybe this person has put the wrong ones in. Bad mistake buying a second hand heli like this - I've dudded myself i think. Guess I'll learn the hard way

10-08-2008, 09:38 AM	#9
phred Registered Users Thread Starter My HF Map location Join Date: Sep 2007 Location: Perth, West Australia	Hmmn, Well now I'm a little more confused. Because having just taken it apart again (wish I had a decent digital camera to post a pic). There are 3 shims on one side and 4 on the other. I'm sure the video showed something similar too. Your diagram shows only possibly two? Cant see the thickness of two shims causing the problem. I just replaced the feathering shaft as it appeared to be ever so slightly bent very tiny. Guess I'll just keep pulling it apart and putting it back together until i can do it in my sleep then - I dunno. Need to think about this. Guess another trip to the LHS is in order. Thanks anyway for the assist - really helps.

10-08-2008, 10:44 AM	#11
phred Registered Users Thread Starter My HF Map location Join Date: Sep 2007 Location: Perth, West Australia	Ok John, Thanks thats noted. I think I'll remove some and leave two on each side. The tamer the better for me. I did just find this website handy http://www.repairblade400.com/#featheringshaft where they lay out the components. What appears wrong on mine is that next to the O ring is no step down washer... this person had it at the other end near the inner end of the blade grip - go figure... Thanks. :o)

10-08-2008, 05:47 PM	#15
neilg. Join Date: Mar 2008 Location: MASSACHUSETTS	if you use the 325mm blades from align you only have to shim the blade grip. maybe the race is not seated properly? if you use the align feathering shaft, it goes like this: cap screw, washer, xtra race, race, cage, race, shim, bearing works for me a little sanding of the align blade will keep capscrew from rubbing against it.