Hello Tony Renshaw!
I suppose that I should throw in the Legal B.S. of - although I cannot
endorse this change and what you do to your plane is your responsibility
sheath used on ezes & other planes. Ive used this process for 550+ hours on
my Long-Ez now & it has worked well for me.
First PLEASE dont consider that this material will constrain the hinge pin.
It will NOT! You still need the hinge pins "locked in" in a mechanical way.
There are several ways that this can be done but it MUST be done. I flew
with a friend up to the Alaska a couple of years ago and he lost one of his
pins on one of his aileron hinges. It caused his plane to pitch up almost to
knife edge. With control input he was able to correct then it would pitch
up again, until he could get it slowed down. With one of the three hinges
(his outboard one) failed, his aileron was about two to three inches back and
down from its normal position in flight. Needless to say this could have
been catastrophic.
If it would be possible, could you please pass on this requirement of having
the hinge pins "Locked In" to anyone that received your first message.
Thanks!
Also be careful to select the correct wire for the replacement hinge pin.
This is a special steel and very hard.
I thought Id comment about lubrication on the hinge. There is still edge to
edge wear on the hinge (i.e. each half against the other) so I still lube the
hinges with TRI-FLOW which has teflon in it.
My hinges have been removed and inspected recently and they are not worn
which is better than most hinges do without using this process.
Hope this helps. Warmest Regards.. Jim Price EAA Mi. Technical Counselor.
<<Gidday all,
I flew recently with a fellow who 3 years ago finished building a VariEze.
He told me of a mod approved downunder and widely used in the US of
sheathing all hinge pins with a teflon coating. Why you need a
dispensation/mod approval is because you need to replace the standard hinge
pin with one 1/2 the diameter and of the required strength. Supposedly the
hinges will wear in 3-500 hours of operation, especially if vibration or
minute flutter comes into play. This is because the hinge pin is so much
tougher than the adjacent soft alloy alluminium hinge. I am concerned about
the flange of the hinges that are rivetted to the various controls such as
the stabilator trim tabs. He tells me that not only will the teflon negate
having to ever replace the hinge, but that you do not need to lubricate them
either as they are self lubricating. Evidently it is very hard to get the
sheathed hinge wire into the hinge but once in it won't come out, so much so
that in the US you didn't need any further locking mechanism. That is not to
say my friend didn't do so howeve,r as he used a method I hadn't heard of by
using 2 small split pins located in small holes through the outboard lug end
of each hinge entrapping it internally. I should also add, the flange that
the hinge mated to provided a physical barrier to the falling/working out of
the pin. I'm finding out more about this sheathing and will send it up the
line when I know more. Simply to wet ones appetite!
Does anyone know any more about this??
Regards
Tony Renshaw
Builder No.236 >>
---------------------
Forwarded message:
From: ToSSi@classic.msn.com (Thomas Scherer)
Date: 97-09-28 20:09:29 EDT
----------
From: owner-europa@ns1.avnet.co.uk on behalf of Tony Renshaw
Subject: Hinge Pin Teflon Sleeving
Gidday all,
I flew recently with a fellow who 3 years ago finished building a VariEze.
He told me of a mod approved downunder and widely used in the US of
sheathing all hinge pins with a teflon coating. Why you need a
dispensation/mod approval is because you need to replace the standard hinge
pin with one 1/2 the diameter and of the required strength. Supposedly the
hinges will wear in 3-500 hours of operation, especially if vibration or
minute flutter comes into play. This is because the hinge pin is so much
tougher than the adjacent soft alloy alluminium hinge. I am concerned about
the flange of the hinges that are rivetted to the various controls such as
the stabilator trim tabs. He tells me that not only will the teflon negate
having to ever replace the hinge, but that you do not need to lubricate them
either as they are self lubricating. Evidently it is very hard to get the
sheathed hinge wire into the hinge but once in it won't come out, so much so
that in the US you didn't need any further locking mechanism. That is not to
say my friend didn't do so howeve,r as he used a method I hadn't heard of by
using 2 small split pins located in small holes through the outboard lug end
of each hinge entrapping it internally. I should also add, the flange that
the hinge mated to provided a physical barrier to the falling/working out of
the pin. I'm finding out more about this sheathing and will send it up the
line when I know more. Simply to wet ones appetite!
Does anyone know any more about this??
Regards
Tony Renshaw
Builder No.236
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