|
Matronics Email Lists Web Forum Interface to the Matronics Email Lists
|
View previous topic :: View next topic |
Author |
Message |
Charles Heathco
Joined: 10 Jan 2006 Posts: 201
|
Posted: Wed Oct 04, 2006 5:42 am Post subject: Nose gear, 6A |
|
|
I mentioned a couple weeks ago finding my nose gear strut bolt loose. I tightened and also took out the spacer for bearing which brought it tight. Now things have looened up again and I have considerable sway on nose gear. Anybody had this problem ? Also, if I need to change the bolt in strut mount, can a slightly larger bolt be found and used? Charlie Heathco
[quote][b]
| - The Matronics RV-List Email Forum - | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?RV-List |
|
|
|
Back to top |
|
|
sportav8r(at)gmail.com Guest
|
Posted: Wed Oct 04, 2006 6:21 am Post subject: Nose gear, 6A |
|
|
Charlie:
Mine had developed a little slop in it years ago, about the time I
replaced the old style leg with the new and had them match-drilled at
a local machine shop. Van's tech-help reply was to drill oversize and
go up to the next standard bolt diameter. I asked about tapered
clevis pins, which I thought intuitively offered the best chance for a
good, snug fit, and the ability to tighten things further if they
loosened again, but they were against that idea. Since then, I've
just kept an eye on it and it has not seemed to worsen, so no fix has
yet been undertaken.
Typically the hole in the weldment socket is what elongates, and the
ultimate repair for that involves welding new metal... yet Van's
refuses to admit they have a problem with this design.
Curious what the spacer is that you removed; mine is just a gear leg
in a tubular socket, secured by a single bolt (too) close to the
firewall. There is no spacer that I recall ever seeing (1994-98
model).
-Stormy
On 10/4/06, Charles Heathco <cheathco(at)cox.net> wrote:
Quote: |
I mentioned a couple weeks ago finding my nose gear strut bolt loose. I
tightened and also took out the spacer for bearing which brought it tight.
Now things have looened up again and I have considerable sway on nose gear.
Anybody had this problem ? Also, if I need to change the bolt in strut
mount, can a slightly larger bolt be found and used? Charlie Heathco
|
| - The Matronics RV-List Email Forum - | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?RV-List |
|
|
|
Back to top |
|
|
Rick Galati
Joined: 10 Jan 2006 Posts: 91 Location: Lake St. Louis MO.
|
Posted: Wed Oct 04, 2006 8:11 am Post subject: Re: re: Nose gear, 6A |
|
|
sportav8r(at)gmail.com wrote: |
Typically the hole in the weldment socket is what elongates, and the
ultimate repair for that involves welding new metal.... |
The first thing I would do is see if an oversize bolt is available and determine if the elongation in the weldment can be cleaned up to that dimension.
An alternative to welding that is more than an acceptable fix is to drill out the elogation in the weldment holes and then press fit repair bushings of the appropriate O.D. and I.D. into the weldment holes. Many competent machine shops can do the work or you might get lucky and find the right size bushings somewhere and do the repair work yourself for minimal cost. The only critical part of the task is insuring the predrilled holes in the weldment are of the precise dimension before attempting to press fit the repair bushings into them.
| - The Matronics RV-List Email Forum - | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?RV-List |
|
|
|
Back to top |
|
|
Leland Collins
Joined: 10 Jan 2006 Posts: 21
|
Posted: Wed Oct 04, 2006 9:15 am Post subject: Re: Nose gear, 6A |
|
|
The Close Tolerance bolts AN175-20A is about four mils larger than the original AN5-20A. Spruce list a drilled version but they were on backorder a week ago. I found some at the Ted Shulgin Co., 925-228-2512. Van's lists an NAS1305-26 bolt that may be the same. Another option is to have a machine shop turn down a 3/8" bolt to the desired dimensions.
Leland
| - The Matronics RV-List Email Forum - | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?RV-List |
|
_________________ Leland
RV9A
N137LC |
|
Back to top |
|
|
Hopperdhh(at)aol.com Guest
|
Posted: Wed Oct 04, 2006 10:16 am Post subject: Nose gear, 6A |
|
|
Charlie,
Take out the bolt and look things over. The bolt itself may show wear that can be corrected with just a new bolt. Also, as another reply suggested, a close tolerance bolt will have a larger diameter. A reamer is necessary to get a really close fit. On my second motor mount (another story) I had a machinist friend use an adjustable reamer to get a perfect fit. Also, I greased up the gear leg and the bolt to try a different approach. Maybe if the joint is lubricated, it won't wear. We'll see how long this one holds up.
I though I had a really good fit when I first built my -7A, but mine loosened up just as you describe in a little over one hundred hours. Van's said it should only happen after thousands of hours. I fly mostly out of grass strips.
As you can tell by taking the prop and moving the nose of the plane left and right, there is quite a bit of torque applied to that joint due to the preload (breakout force) on the castor joint at the bottom. >From the axis of the gear leg in the engine mount to where the nose wheel touches the ground there is about a foot of leverage on the gear leg to apply this torque. If the joint at the top cannot handle this torque, I would consider it a design issue.
In my opinion, the joint should be stronger. A larger bolt (3/8 inch) and doublers on the weldment would beef up the joint. But, I'm not sure there is room given the narrow shoulder at the top of the present gear leg. Could an Allen head die bolt be used here with doublers to increase the area on the engine mount? I am not a bona fide mechanical engineer, so I am not going to modify the design. I hope that those at Van's will address this problem, though.
I hope others with nose wheel airplanes will let us know if we are in the minority, or if all of these joints loosen up. Is a grass runway harder on this joint than pavement?
Dan Hopper
RV-7A
In a message dated 10/4/2006 9:44:36 A.M. Eastern Daylight Time, cheathco(at)cox.net writes:
Quote: | I mentioned a couple weeks ago finding my nose gear strut bolt loose. I tightened and also took out the spacer for bearing which brought it tight. Now things have looened up again and I have considerable sway on nose gear. Anybody had this problem ? Also, if I need to change the bolt in strut mount, can a slightly larger bolt be found and used? Charlie Heathco
|
[quote][b]
| - The Matronics RV-List Email Forum - | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?RV-List |
|
|
|
Back to top |
|
|
pitts_pilot(at)bellsouth. Guest
|
Posted: Wed Oct 04, 2006 12:35 pm Post subject: Nose gear, 6A |
|
|
Leland Collins wrote:
Quote: |
The Close Tolerance bolts AN175-20A is about four mils larger than the original AN5-20A. Spruce list a drilled version but they were on backorder a week ago. I found some at the Ted Shulgin Co., 925-228-2512. Van's lists an NAS1305-26 bolt that may be the same. Another option is to have a machine shop turn down a 3/8" bolt to the desired dimensions.
I don't like that idea ..... but that's only MHO. The lathe work will
|
leave small grooves (unless they're finish ground) which is a great
place for stress fractures to start.
Linn
do not archive
| - The Matronics RV-List Email Forum - | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?RV-List |
|
|
|
Back to top |
|
|
Jim Ellis
Joined: 26 Jan 2006 Posts: 11
|
Posted: Wed Oct 04, 2006 2:08 pm Post subject: Re: Nose gear, 6A |
|
|
Charlie,
Take a look at the following webpage. This is for a 9A, but it might work for a 6A also.
http://www.rvwiki.org/index.php?title=Nose_Gear_Strut
Jim Ellis
RV9-A, Flying
| - The Matronics RV-List Email Forum - | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?RV-List |
|
|
|
Back to top |
|
|
sportav8r(at)gmail.com Guest
|
Posted: Thu Oct 05, 2006 3:58 am Post subject: Nose gear, 6A |
|
|
Plus no cad plating and I doubt you'll get rolled (vs. cut) threads.
I don't thinl I'd go that way either.
$.02
Stormy
On 10/4/06, linn Walters <pitts_pilot(at)bellsouth.net> wrote:
Quote: |
Leland Collins wrote:
>
>
>The Close Tolerance bolts AN175-20A is about four mils larger than the original AN5-20A. Spruce list a drilled version but they were on backorder a week ago. I found some at the Ted Shulgin Co., 925-228-2512. Van's lists an NAS1305-26 bolt that may be the same. Another option is to have a machine shop turn down a 3/8" bolt to the desired dimensions.
>
I don't like that idea ..... but that's only MHO. The lathe work will
leave small grooves (unless they're finish ground) which is a great
place for stress fractures to start.
Linn
do not archive
>
>Leland
>
>--------
>Leland
>RV9A
>N137LC
>
>
>
>
>Read this topic online here:
>
>http://forums.matronics.com/viewtopic.php?p=65769#65769
>
>
>
>
>
>
>
>
>
>
>
>
>
|
| - The Matronics RV-List Email Forum - | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?RV-List |
|
|
|
Back to top |
|
|
|
|
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum You cannot attach files in this forum You can download files in this forum
|
Powered by phpBB © 2001, 2005 phpBB Group
|