The Murphy Builders Site

Thanks Wayne. You bring up a good comment re # of points of failure. Current 0.125, non bearing, loose config leads to elongated holes which a # of flying Moose have. I value your wise input!

"Wayne G. O'Shea"<oifa@irishfield.on.ca> wrote:

Definitely stout Ted.

As for the originals.. I don't know if Darryl Murphy made them that way
because they were simple to make from angle stock.. or to offer dual load
path/failure integrity like many of his fittings?!

Wayne

----- Original Message -----
From: "Ted Waltman"<ted@vafm.org>
To:<rebel-builders@dcsol.com>
Sent: Thursday, January 13, 2011 11:15 AM
Subject: [rebel-builders] Moose& Elite new elevator and new horizontal
stabilizer hinge/brackets

Folks,



I just uploaded six pictures to Area 122-S/M After Market Products. These
pictures show a new design for both Moose and Elite elevator/horizontal
stabilizer hinge brackets. I sent out a previous email on this subject
back
in November. If you can't view the pictures on the list, send me a
private
email (tedwaltman@gmail.com) and I'll email you part pictures.



Thank you for your patience while I worked through getting actual
pre-production prototypes built by a machine shop. The attached pictures
show multiple views of the final product.



As you know, the new design replaces existing four-separate-pieces (total
4
individual parts per "pair" in other words). The original parts are each
individually 6061 T6 0.125" thick. So ST-318 as originally part of the
kit
is composed of two parts sandwiched together. Each "ear" of EL-300 is
0.0125" (picture labeled "original.jpg").



The rest of the attached pictures show the new design-- 0.250" 6061 T6
hinge
bracket pairs. Each ear of EL-300 is now 0.250" thick. In my original
email, I mentioned perhaps making these hinge/bracket (H/B) pairs out of
2024 T3, which is approximately 20% to 25% stronger. Upon further
reflection, I thought to myself, "Gee, we're bolting this already much
stronger assembly to a spar that itself thinner 6061 T6--so why make this
hinge/bracket pair out of so much stronger material that it then makes the
spar itself the weak point?" Hence, the new H/B design will be made out
of
6061 T6.



The bearing you see on the ST-318 is a MS27641 sealed bearing. Sealed to
prevent moisture/dirt contamination down the road. Radial load bearing is
1100 lbs and thrust load bearing is 900 lbs in this 1/4" bearing size.
Once
again, the sealed aspect keeps things clean from the elements, something
that is clearly needed back on the elevator/horizontal stabilizer. The
bearing is pressed in and sealed with red Loctite.



The four mount holes on each piece are in the same exact position as on
the
standard parts. Hence these after-market H/B pieces will bolt directly to
your existing spars.



There is 0.005" clearance on each side of EL-300 for ST-318 to fit in
between. This is a tight fit! We could (but are not) open up the spacing
to allow for a AN960-416L (0.016") or AN960-416 (0.032") washer. Doing so
however would allow for a bit of slop in case you had a spar just a tad
bit
out of perfect true. It would be, as you can well imagine, be an absolute
bear to get those washers in place. Our current plan is therefore to
leave
the clearance as-is--0.005" each side or 0.010" total. If you need to
realign anything, you will need to do so by perhaps reaming out one or
more
of the four spar-mount holes on each side.



You do not want any slop in this assembly. Slop is what causes starts and
accentuates hole elongation in EL-300 (which is what led me to start this
whole endeavor!). With this new design, which again only has 0.005" on
each
side between each ear of EL-300 and the side of ST-318, you put the two
pieces together and tighten the bolt/nut fully together--tightly together.
With the design we have here, the bearing has an outer surface against
which
you chinch up--tighten--the ears of the EL-300. (Note: If we were to
allow
for the use of washers, you would have to insure you get the washers in
place and again fully tighten the nut/bolt assembly together. In this
example, the washer would not be a rotating surface but only a spacer.)
There must be no--zero--side to side play or you will, even with this new
design, eventually--further down the road at least--end up with hole
elongation in EL-300.



Because this new design does not have a rotating bolt, one can use a
standard AN365 fiber nut and a standard AN4-10 bolt--there is no need for
a
AN310-4 castle nut, MS24665-132 cotter pin, AN960-516 washers and drilled
AN-4-10A bolts.



Assembly: Due to the tight tolerance, I suggest you first bolt the EL-300
and ST-318 assembly together with the 4 AN-3 spar mount bolts on each side
only loosely installed. Keeping the AN-3 bolts very loose (nut only hand
tight) will give you a few thousands play which will make the pairing of
EL-300/ST-318 much easier. Fully tighten the AN4/AN365 nut/bolt then, and
only then, tighten the AN-3 nut/bolts down on the respective spars.



There are 5 pairs of H/B on the Moose Elevator/H-stab and 3 pairs of H/B
on
the Moose fin/rudder. I believe the Elite would require 4 EL-300 on the
rudder, 4 EL-300 on the Elevator, 3 ST-318 on the horizontal stabilizer
and
3 ST-318 on the vertical fin (someone please check my #'s on the Elite).



I strongly encourage Moose folks to at least replace each outer-most pair
on
the elevator/h-stab.



Availability: First week in February for initial production run.



Pricing:

- Those who firmly commit to and pay for an order prior to
Feb 1st: $75 per pair EL-300/ST-318 (plus shipping/handling of $10 U.S.;
Canada $15)

- After Feb 1st the price goes up to $90 a pair (plus
shipping/handling of $10 U.S.; Canada $15)



Shipping/handling charge is for total order--not for each pair.



I'll provide a PayPal account for remittances.



Please email of course with any questions. Again, thank you for your
interest.



Ted Waltman

tedwaltman@gmail.com

303-378-4987





-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------

-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------

-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------