Libelle spoilers

On Tuesday, September 13, 2016 at 2:06:01 PM UTC-7, Martin Gregorie wrote:

DU?

Please, Herr Gregorie, I hardly know you.

But seriously, I was wondering that myself. The last time I heard of DU in the context of materials, it was the _depleted uranium_ used for 30mm cannon shells of the A10 Warthog and the mass balances in early Boeing jetliners.

--Bob K.

At 17:00 29 September 2017, wrote:
Hi JJ, you may just be able to save my life! I also have a standard
Libelle=
with only 650 hours on it. But the airbrakes are really stiff and it is
cl=
ear it is the gearbox in the wing roots. I have tried to get lubrication
in=
there and failed and want to drill the 2mm holes. But, where exactly do
I
=
drill them and what lubricant would you recommend pleas

Hi just think of what may be the cause

If the problem is caused due to internal corrosion squirting oil in will
not cure it, corrosion grows and tightens things up have you correctly
idetified the tight component.
KF

Sorry I don't have a Libelle any more, but I'd drill the 2mm hole in the middle of the gear boxi (visible from the root rib). Much too earl in the year to start the annual discussion about lubricants, but I'm still using WD-40 ...........or other suitable spray lubricants of your choice!
JJ

Originally Posted by

Sorry I don't have a Libelle any more, but I'd drill the 2mm hole in the middle of the gear boxi (visible from the root rib). Much too earl in the year to start the annual discussion about lubricants, but I'm still using WD-40 ...........or other suitable spray lubricants of your choice!
JJ

I have the drawings for the Kestrel gearbox and there are no separate bearings DU or otherwise as such in the gearbox, just Glasflugel's standard ptfe tape and resin mix embedded in the shells of the gearbox. I think the stiffness comes from both the contraction of the resin over the years and the corrosion of the unprotected steel shaft. My Kestrel air brakes can get stiff, and I use a light ptfe lubricant half way along the shaft to creep into the pure bearings, as per JJ's method, and by taking off the small cap on the external end of the drive dogs (is this on Libelles? I think not...) I can inject some heavier weight oil onto the gears themselves. Needs to be done ever two or three years sadly but it makes the brakes usable. I keep thinking of a major rework and replacing the gearbox with a modern right angle drive.

On Friday, September 29, 2017 at 8:39:27 PM UTC+2, Bob Kuykendall wrote:
On Tuesday, September 13, 2016 at 2:06:01 PM UTC-7, Martin Gregorie wrote:

DU?

Please, Herr Gregorie, I hardly know you.

But seriously, I was wondering that myself. The last time I heard of DU in the context of materials, it was the _depleted uranium_ used for 30mm cannon shells of the A10 Warthog and the mass balances in early Boeing jetliners.

--Bob K.

Bob,

DU is a brand name or type designation of a bushing made by IGUS.

Uli

On Fri, 29 Sep 2017 11:39:26 -0700, Bob Kuykendall wrote:

On Tuesday, September 13, 2016 at 2:06:01 PM UTC-7, Martin Gregorie
wrote:

DU?

Please, Herr Gregorie, I hardly know you.

Hi Bob,

I've just back from a club expedition to Eden Soaring, where I had fun
ridge running with my Libelle on the Pennines around Cross Fell. We had
three good days despite the prevailing S - SSE wind and the inevitable
messy result of many sheep camping overnight on the airfield.

However, I don't remember mentioning DU (could it have been a mis-
spelling?) in connection with a Libelle and all earlier posts in this
thread have now been eaten by the Chronophage so I can't see the context.

My brakes are currently as silky smooth as they've ever been, largely
thanks to judicious application of a medium viscosity machine oil to the
airbrake bearings in the wing root.

But seriously, I was wondering that myself. The last time I heard of DU
in the context of materials, it was the _depleted uranium_ used for 30mm
cannon shells of the A10 Warthog and the mass balances in early Boeing
jetliners.

Same here, though I didn't know about the Boeing mass balances, and lets
not even mention the rectangular lumps of iron in the nose of a Slingsby
Vega.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |