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Author Topic: Main Gears - How should they sit?  (Read 1360 times)

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Dan_Root

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Main Gears - How should they sit?
« on: September 27, 2016, 09:29:58 AM »
I don't have a hosting site to link a picture to, I'll try to describe:

L8A Main Gears seem to have more negative camber than they should.  As-in, are my mains sagging?  For Luscombe savvy folks, I have the updated F mains with the center spring, not bands or rods.  The toe is good, but seems like the main wheels should have almost 0 degrees or even a little positive camber?
L8A - Slightly modified

will moffitt

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Re: Main Gears - How should they sit?
« Reply #1 on: September 27, 2016, 07:02:18 PM »
Speaking as a fellow that has had many bad landings which made me wonder how old I really am.  Investigation found problems, I corrected the toe with a pipe over the axle, a small come a long from the pipe end of the fuselage.  Very little effort required.  Fixed it.  I used to say landing this little thing was the combination of an orgasm and a near death experience.  The death part is gone.  I would say if it lands good and does not throw you to one side leave it alone.  For what it is worth.

will

hotrod180

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Re: Main Gears - How should they sit?
« Reply #2 on: September 27, 2016, 08:08:06 PM »
Are you a member of the Luscombe Club?
Actually I believe there are two Luscombe clubs--
the Luscombe Assn
http://www.luscombeassoc.org/

and the Continental Luscombe Assn.
https://luscombecla.com/

There's also the Luscombe Foundation / Luscombe Endowment.
www.luscombe.org

Type clubs & organizations and/or type-specific websites are usually the best place for information like that.


Dan_Root

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Re: Main Gears - How should they sit?
« Reply #3 on: September 29, 2016, 07:26:35 AM »
Thanks!

I haven't joined any Luscombe clubs (bad on me!) yet.

Lands perfectly unless I manage to botch things up a bit.  I'll check out some specific information to the model.
L8A - Slightly modified

will moffitt

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Re: Main Gears - How should they sit?
« Reply #4 on: September 29, 2016, 08:01:23 AM »
A good friend has a Luscombe and it is a pussy cat to land compared to mine.  I am happy with all the tweaking I have done to get the plane to handle as as good as it does now.  I see anything else at the point of diminishing return.  Any screw up now is on me.

will

hotrod180

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Re: Main Gears - How should they sit?
« Reply #5 on: September 29, 2016, 08:31:21 AM »
FWIW most taildraggers that I see usually have some positive camber (top of wheel out) in the mains when at rest. Worse case, they are neutral. That usually gives lots of room for them to flex in the negative direction. Sounds like you're saying yours are negative. That doesn't sound like a good thing, unfortunately I don't have enough knowledge of the Luscombe landing gear to suggest a fix. Hence my comment about the type clubs.

Dan_Root

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Re: Main Gears - How should they sit?
« Reply #6 on: September 29, 2016, 10:30:29 AM »
hotrod180 - Correct, both mains are negative, one a little more than the other.  I've known this to not be preffered since I was a student.  Most tailwheels I've seen are either striaght or have a slight positive camber.  There are adjustments that can be made and I'll solicit the assistance of an AP as it could radically change the behavior when wheels first touch earth again.
L8A - Slightly modified

Jasona900

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Re: Main Gears - How should they sit?
« Reply #7 on: September 30, 2016, 05:22:24 PM »
Do you have wear on the inside our outside of your tires?  If it's inside, chances are it may be time for a new spring and/or strut.   I haven't changed either, but I understand it's a bit of a process since you have to strap and hang the fuselage from the hangar ceiling before you remove the assembly.  If you were to remove the bolt below the fuselage between the main gear without first supporting the airplane, the whole airplane would come crashing to the ground.  Best to have someone who has done it before help. 

hotrod180

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Re: Main Gears - How should they sit?
« Reply #8 on: October 01, 2016, 09:39:44 AM »
BTW if you do this....
I've seen people support the airplane with an engine hoist hooked to the lifting eye bolted to the engine case.
NOT a good idea, that's for lifting the engine only.

Dan_Root

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Re: Main Gears - How should they sit?
« Reply #9 on: October 04, 2016, 09:56:52 AM »
Yes, inside of tires have more wear than outside.  The main spring is sagging.  I haven't looked to see if there is adjustment yet.  I'd love to pick up a set of wing jacks.  I wouldn't do any adjusting without an AP's assistance of course.  Little things I do myself, but possibly changing the behavior of flight/landing/take off solicits an AP/AI's assistance.
L8A - Slightly modified

will moffitt

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Re: Main Gears - How should they sit?
« Reply #10 on: October 04, 2016, 01:19:34 PM »
I was going through tires on my  150.  We put 5 sacks of cement in it, (fuel and people) pushed it back and forth to normalize the wheel position.  Cessnas have wedge shaped spacers where the axle bolts to the spring gear.  The next set of tires lasted a long time.

will

Dan_Root

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Re: Main Gears - How should they sit?
« Reply #11 on: October 06, 2016, 07:44:59 AM »
I was going through tires on my  150.  We put 5 sacks of cement in it, (fuel and people) pushed it back and forth to normalize the wheel position.  Cessnas have wedge shaped spacers where the axle bolts to the spring gear.  The next set of tires lasted a long time.

will

Will,

Exactly my concern, behavior on landing and TO is great, but tire wear is too fast.  I still need to look into how Luscombe camber is adjusted.  I think it's central to the spring etc.  I've also been looking closer at other tailwheel aircraft and 95% of them seem to have 0 camber or slightly pos camber.  My neg camber clearly isn't correct.
L8A - Slightly modified