REFLECTOR: Canard Center Hinge

Richard J. Gentil richard at naples-air-center.com
Tue Mar 22 19:34:07 CDT 2011


Mystery Solved

I had a little time this afternoon so I pulled the canard. It turned out the previous owner of my kit, some 10+ years ago had moded the center hinge bushings in favor of bearings. Two issues with the mod,  first, the bearings were too small so there was play. You can see the old bearing next to one of the new ones:



Second he had pressed in the center hinge a plastic bearing which had a lip on the outside of each side of the center hinge, this meant that the bolt holding the bearings could pivot and that is why I ended up with the split in the elevators. 

The new bearings, thanks Don, will fit tight so no play. And I removed the plastic lip on each side of the center hinge so the washers against the center hinge will lay flat, not allowing any play in the bolt. If I remember Friday to take pictures and I reassemble the canard, I will send a picture of the new assembly. 

Richard

Sent from my iPhone 4

On Mar 21, 2011, at 7:47 PM, "Scott Baker" <scottb33333 at gmail.com> wrote:

> The relative locations of the trim spring and the 'sparrow strainer' should not affect the differential elevator positions that you are seeing.
> If the elevator positions are changing relative to one another in flight, you should be able to duplicate this movement on the ground.
> Immobilize one of the elevators by 'C-clamping" it to the wing tip.  Manipulate the opposite elevator to see if there is movement.
> If movement is present, determine where the 'slop' is occuring.  It may be in the outboard bushings of the concentric elevator torque tubes; or where the left and right torque tubes are joined together.  Note: be sure to use two bolts to attach the left and right elevator torque tubes together.  The one bolt that connects the elevator push-pull rod end to the torque tubes is not, in itself, enough.  Tighten everything to ensure both elevators work together and do not slip differentially.
> Scott B.
> ----- Original Message -----
> From: Richard J. Gentil
> To: Velocity Aircraft Owners and Builders list
> Sent: Monday, March 21, 2011 7:14 PM
> Subject: Re: REFLECTOR: Canard Center Hinge
> 
> Question I have, I attached the Sparrow on the right side elevator and I have the trim spring attached to the left side elevator torque tube. I am wondering if this is contributing to the issue since they are opposing forces on the elevator. 
> 
> I am wondering if it would be worth moving the sparrow to the left elevator so the trim spring and sparrow are on the same side. (Due to the avionics there was no room for the trim spring on the right elevator torque tube.)
> 
> Is there a specific reason the factory calls for the trim spring on the left and the sparrow on the right?
> 
> Richard
> 
> Sent from my iPhone 4
> 
> On Mar 21, 2011, at 12:23 PM, "Richard J. Gentil" <richard at naples-air-center.com> wrote:
> 
>> Al,
>> 
>> That would be fantastic thank you!
>> 
>> Richard
>> 
>> Sent from my iPhone 4
>> 
>> On Mar 21, 2011, at 1:03 PM, "Al Gietzen" <ALVentures at cox.net> wrote:
>> 
>>> Richard;
>>> 
>>>  
>>> 
>>> I used self-aligning ball bearings that bolt to the center pivot support.  The o.d. of these bearings fit snugly inside the ends of the torque tubes (concentric version). I haven’t been able to find a photo. With some research I could probably find the bearing part # (from Aircraft Spruce).
>>> 
>>>  
>>> 
>>> Al
>>> 
>>>  
>>> 
>>> -----Original Message-----
>>> From: reflector-bounces at tvbf.org [mailto:reflector-bounces at tvbf.org] On Behalf Of Richard J. Gentil
>>> Sent: Sunday, March 20, 2011 11:16 AM
>>> To: Velocity Aircraft Owners and Builders list
>>> Subject: Re: REFLECTOR: Canard Center Hinge
>>> 
>>>  
>>> 
>>> Dennis,
>>> 
>>>  
>>> 
>>> I would appreciate pictures and yes I am talking about the bushing dead        center. 
>>> 
>>>  
>>> 
>>> Richard
>>> 
>>> Sent from my iPhone 4
>>> 
>>> 
>>> On Mar 20, 2011, at 1:21 PM, Dennis Martin <dennis.doc at gmail.com>        wrote:
>>> 
>>>> Are we talking about the bushing at dead center between the two elevators? If so, I redesigned that. I inserted needle bearings inside each elevator tube. Next I took a steel shaft (recycled from an electric motor) and inserted it in aluminum fork in the middle. Now each elevator tube slides into the steel shaft. No way for it to work loose. I can send photos if anyone's interested.
>>>> 
>>>> Dennis
>>>> 
>>>> On Sat, Mar 19, 2011 at 9:25 PM, Richard J. Gentil <richard at naples-air-center.com> wrote:
>>>> 
>>>> I was on my third test flight today and I noticed the elevators  were no longer trailing at the same angle so I landed immediately. Here are the shots from 5,500 feet at 120kts IAS          (130kts TAS). 
>>>> 
>>>> 
>>>> 
>>>> (Second picture of the canard will be in the next email.)
>>>> 
>>>> 
>>>> After landing I seem to have some play at the oilite bushing. Everything else is tight from what I can tell. All that is left is the bushing. From what I am guessing is that the left elevator has the pressure of the pitch trim spring and the right elevator has the downward pressure of the sparrow strainer. 
>>>> 
>>>> Any ideas would be helpful. My plan is to remove the canard and examine the oilite bushing. 
>>>> 
>>>> Richard
>>>> 
>>>> Sent from my iPhone 4
>>>> 
>>>> 
>>>> _______________________________________________
>>>> To change your email address, visit http://www.tvbf.org/mailman/listinfo/reflector
>>>> 
>>>> Visit the gallery!  www.tvbf.org/gallery
>>>> user:pw = tvbf:jamaicangoose
>>>> Check new archives: www.tvbf.org/pipermail
>>>> Check old archives: http://www.tvbf.org/archives/velocity/maillist.html
>>>> 
>>>> 
>>>> 
>>>> 
>>>> -- 
>>>> All the best,
>>>> Dennis
>>>> 
>>> 
>>>> _______________________________________________
>>>> To change your email address, visit http://www.tvbf.org/mailman/listinfo/reflector
>>>> 
>>>> Visit the gallery!  www.tvbf.org/gallery
>>>> user:pw = tvbf:jamaicangoose
>>>> Check new archives: www.tvbf.org/pipermail
>>>> Check old archives: http://www.tvbf.org/archives/velocity/maillist.html
>>>> 
>> 
>>> _______________________________________________
>>> To change your email address, visit http://www.tvbf.org/mailman/listinfo/reflector
>>> 
>>> Visit the gallery!  www.tvbf.org/gallery
>>> user:pw = tvbf:jamaicangoose
>>> Check new archives: www.tvbf.org/pipermail
>>> Check old archives: http://www.tvbf.org/archives/velocity/maillist.html
> 
>> _______________________________________________
>> To change your email address, visit http://www.tvbf.org/mailman/listinfo/reflector
>> 
>> Visit the gallery!  www.tvbf.org/gallery
>> user:pw = tvbf:jamaicangoose
>> Check new archives: www.tvbf.org/pipermail
>> Check old archives: http://www.tvbf.org/archives/velocity/maillist.html
> 
> _______________________________________________
> To change your email address, visit http://www.tvbf.org/mailman/listinfo/reflector
> 
> Visit the gallery!  www.tvbf.org/gallery
> user:pw = tvbf:jamaicangoose
> Check new archives: www.tvbf.org/pipermail
> Check old archives: http://www.tvbf.org/archives/velocity/maillist.html
> _______________________________________________
> To change your email address, visit http://www.tvbf.org/mailman/listinfo/reflector
> 
> Visit the gallery!  www.tvbf.org/gallery
> user:pw = tvbf:jamaicangoose
> Check new archives: www.tvbf.org/pipermail
> Check old archives: http://www.tvbf.org/archives/velocity/maillist.html
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.tvbf.org/mailman/private/reflector/attachments/20110322/8a7eb1f0/attachment-0001.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image.jpeg
Type: image/jpeg
Size: 534971 bytes
Desc: not available
URL: <http://www.tvbf.org/mailman/private/reflector/attachments/20110322/8a7eb1f0/attachment-0001.jpeg>


More information about the Reflector mailing list