lml@lancaironline.net Mailing List Archive

I did not calculate this. But the thread looks very tiny to me (in relation to the tube). If you do not every time completely screw in the male piece you get a bending momentum on the thread. With the fairly long arm of the pump handle and the quite high hand force to lock the gear you will get a quite large bending momentum on this thread which will bend it in the beginning and then might lead to failure. Like I said I did not calculate it – the proportions just did not look beautiful to me (my professor used to say: if a design looks beautiful (in regards to proportions) it is most likely good… If it has to be a two piece design I would take a piece of tube (2” long) that fits tight on the outside or inside (with a thicker wall then) on or inside the cut off pieces and weld it to the removable piece. To pump (in case you find the handle at night) you just stick it on

Ralf

From: vtailjeff@aol.com [mailto:vtailjeff@aol.com]
Sent: Monday, October 17, 2011 2:00 PM
To: lml@lancaironline.net
Subject: Re: [LML] Re: Gear Hand Pump LIV

Its night time.... you are IMC shooting an instrument approach and the gear does not come down...where the hell is that handle?

-----Original Message-----
From: jeffrey liegner <liegner@ptd.net>
To: lml <lml@lancaironline.net>
Sent: Mon, Oct 17, 2011 7:44 am
Subject: [LML] Re: Gear Hand Pump LIV

To: lml@lancaironline.net

From: "Jeffrey Liegner, MD" <liegner@embarqmail.com>

Subject: Re: [LML] Re: Gear Hand Pump LIV

Cc: "William A. Hogarty" <billhogarty@gmail.com>

Bcc:

X-Attachments: :Macintosh HD:402137:Gear Hand Pump LIV.1.jpg: :Macintosh

HD:402137:Gear Hand Pump LIV.2.jpg:

Here's a basic camera photo of the Gear Hand Pump handle mod.

re:  Hydraullic pump mod:

Jeff:  A picture of your mod would be appreciated.  Also, what did the mod

cost.?

Thanks, Bill Hogarty

On Thu, Sep 1, 2011 at 10:27 AM, <<mailto:liegner@earthlink.net>liegner@earthlink.net>

wrote:

Brad Simmons (talented professional builder in Milan TN)

has shown me a modification to the

gear handle that solved this problem.  The leaking hydralics at the

pump housing (which I had rebuilt three of four times to stop this)

must come from these little bumps and wiggles occurring against the

handle, permitting hydralic fluid to sneak past the seals.

Using a machinist, the handle is cut short leaving ~40% (coming off

the pump), and a female fitting incorporated into the cut end.  The

other 60% handle (with the bulb on end) gets a long male screw

mounted inside the hollow end.  When screwed together, the handle is

solid.  The 60% handle then sits elsewhere (side pouch or behind the

passenger front seat or cleated under the front spar lip).

This opens up the entire leg area previously blocked by the handle

projecting out over the spar, and also significantly reduces the

presence of the handle/pump profile sitting between the seats.

Without the occasional bumps on the handle, small leakage from the

pump seals seems to have stopped.

I sent my handle to Brad <<mailto:dl60280@bellsouth.net>dl60280@bellsouth.net>

and he returned it

in two weeks machined and ready for reinstall.

Jeff Liegner

LIVP in New Jersey

>To:  <mailto:lml@lancaironline.net>lml@lancaironline.net

>From: "Nicholas Paczkowski" <<mailto:npaczkowski@telus.net>npaczkowski@telus.net>

>Subject: Gear Hand Pump LIV

>Perhaps a dumb question (apologies in advance) but Is there a better

>alternative available to the manually operated hydraulic 'gear down'

>lever (such as a charged gas bottle) that would eliminate both the

>awkward lever and the seemingly inevitable leaking of hydraulic

>fluid? Thanks.

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