B-47 9th Scale, Boeing Stratojet...In The Middle

[Capt. Midnight]

Hi Ed!

Wow! I had not realized you had increased the planned size of your model so dramatically - I mean, that puppy is going to be BIG!! Are you designing a special truck to carry it to the launch site??

Seriously, are you planning to use turbines now (rather than the fans)? Do you have a target weight?

Dave P.

[Flite-Metal]

David,

No, as seen in post #1 little has changed. We are as we were. What began as 1:8.6930 scale ended up with 1:8.7669 scale.
A mere.0739" difference from what we began with 12/10/2009 @ 09:30 PM ;^)

What you are not used to seeing is a final dim declaration. A final is the result of all the individual sections of the project are
now brought back together in preparation for assembly after each is created indivdually.

Sam and I often refer to this as assembly of what we have kitted out. Final dims are necessary because of individual section
accumulative error. Unless CAD is utilized in a project you will accumulate errors due to the limitations of the software utilized
during design. To offset accumulative error I try to maintain a dims measurements to four decimal places. Working in 10ths is
an advantage. Since I worked in the business forms industry prior to my career in electronic directed task systems.

Microsoft Image Composer has an upper working edit limit between 4800 and 6000 pixels. Because of this I utilize multiple
software products to create a project. Here is what I have used during this project. For example the w/s shown on a file
name is incorrect as it references a previous w/s of 159.4442" as we moved forward when in reality after its edited w/s is
158.7783".



Those following the first and current thread..."In The Beginning" and "In The Middle" have if they are keeping tabs on dims...
seen them grow then shrink back as various components come together as "unit sets" to become the sum of all parts.

Anyone, who has ever used xerographic processes to design a model are familair with myopic accumulative error. It is what
it is for X $. You get exactly what you don't pay for...and therefore have to learn workarounds.

As for transport, I covered that a long time back in these threads. Below is another image of it. This is not set in stone as I
have in this been trying my best to avoid using a trailer.

This is not to say there are not other projects on my horizon which are going to require a trailer and possibly a van or Sprinter.
Spinters are more practical than $15k trailers as the $ differential in cost of operation and ease of use are not even close to
a gasoline Ford Expedition towing a fully covered tandem trailer.



David, as you will remember the target AUW has always been just under 15 kilo sans batteries. As for square inches I have
yet to calculate it, as that is of no consequence to this project. Four decimal places provide for a more accurate raster to
vector conversion.

Analog drawings shown in the first two of this project's three theads were converted to digital .stl and other image files to
permit CNC printing, milling, and hot wiring as has been explained and illustrated in the earlier and this thread.

A turbine powered B-47 would be extremely problematic to say nothing for it being huge to accommodate everything that is
required since biforcating a turbine is impractical. I am sure someone will attempt it as I originally thought I would prior to
investigating it.

[Capt. Midnight]

Hi Ed!

OK, thanks for the semi-feedback: what's your target weight and what does you magical computer system give for a wing area?

Also, what is the significance of the 4-decimal-point significant figures in your dimensional data list? Are these values that you need to plug into a numerical control machine to create the various parts of the model?

Cheers,

Dave P.

[Flite-Metal]

Nothing special about my 7 year old Intel 3G P4 PC's.

Since FAI F4C's weight limit is 15 kilos sans batteries, the B-47's will weigh somewhere close to 27#~28#. There is no limit on
electric F4C all up flying weight.

Numerical control machine... The four place dims are necessary to work with the multiple programs, printers, mills, and hot wire
used to create our B-47's. Kinda sorta correct does not yield accurate models. More or less this is the same as measure twice
and cut once. In our case we measure, measure, and measure again to mean out accumulative errors.

Sam and I have purchased and will purchase additional CNC tools to enable us to build more accurately in less time for pennies
compared to the multiple dollars and countless hours of traditional scratch building you are all too familiar with. Of course there
is always the time required to gather and drill down through documentation to determine what is correct and not correct about
a subject.

The answer to why this project size has been a moving target is its size is the sum of its parts. The only constant has been the
FSA of the Dynamax EDF since I chose it over Mr. Maxwell's StuMax 52. The batteries for the Dynamax have constantly gotten
smaller and lighter though their capaciy has constantly increased.

[Flite-Metal]

Below are two of our final drawing configurations from which dims were derived.

[Flite-Metal]

After what happened at FedEx Kinko's yesterday evening I feel I should warn you when you go to print your full size images.
When you print computer images of this size you create a small control image extracted from within your larger composition.


In this case I used the 8.283" declaration on the drawing to create a control file. The control file is used to determine the
differential between what you created using a software product at a specific size and the size it prints as.

While it would be nice to think once created it would print properly on any printer, that is not necessarily the case and is
more often than not...In this case the 8.283" factor in our dim equation is used as the control print.

After printing the control file (8.283") and measuring it to be sure it actually printed at 8.283" you then are assured all files
designed with this control image are going to print properly.... IF...

1). Print the control image, in this case it is 8.283" long.
2). Measure the printed 8.283" control image.
3). Adjust the print size % by the difference between the file and the printed image size.
4). Measure the printed 8.283" control image.
5). Adjust the print size % by the difference between the file and the printed image size.
6). When printed size matches the declared size, print all your image files at the same %
of either reduction or enlargement applied to the control image to achieve proper size.

The FedEx Office aka Kinko's I have used for almost 20 years is no longer capable of printing files using a prescribed size...
if you dare believe such a thing could happen. The print service manager said I needed to provide him an explicit image
at full size, ready to print.

After he printed the 8.283" control image its printed length was 8.1" or in other words it was too small by 2.21%. When
I asked him to print it again and increase its size by 102.21% he said he could not do it. He turned the screen around to
let me see...yes it was asking for width and length not a % of the original to-be-printed images.

He told me the self service work station no longer drove the large format printer. The computer on his desk was the only
control computer for the entire store. Folks, a lot has changed at FedEx Office, none of it is good for modelers.

What's next amidst all this obamanation...

[Flite-Metal]

We're approaching disclosure of Sam's revised (scale) flap redesign so I think it is appropriate to post images in support of people
replicating this design project.

Images were shot as if moving across underside surface of the wing at the fuselage intersect. Typically this appears on plastic models
as a fillet. However, in reality it is not attached to the fuselage as seen here on this displayed B-47 in Charlestown, South Carolina. It
was shot by Sam on a recent business trip.







It is assumed these hex head bolts and reinforcement panels/doublers are necessary because something was removed and the
aluminum panels would otherwise simply hang down unless they were attached to something inside the fuselage. This is at the
rear spar location.




Below is the intersect of the left wing with the fuselage showing a triangular leading edge doubler and short fillet. Balance of
the fuselage panel is flush with the bottom the wing without a fillet. There is a wide gap between the wing and the fuselage
all across the top of the wing on all B-47E's and WB-47's. Note, there is a wing L.E. doubler beneath the left wing image.




On the other end of the inboard flap you will find another unique feature of the inboard flap. The outside leading edge corner of the
inboard flap slips beneath the inboard nacelle pylon trailing fillet when it is in the up and locked position.











Note the leading edge of the flap closest to the inboard pylon is tucked back under the edge of the pylon when it is up.

[Flite-Metal]

The model sections which follow are breakdowns along scale airframe line per these Boeing maintenance manual illustrations:

[Flite-Metal]

Closing several open ended items this week. The Salon Quality Dry Transfers for one.

[Flite-Metal]

Working across the canopy composition. Asked Dave for his input comparing the below cross section dims to his successful
canopy creation. Canopy sits across the slope of the front fuselage.

I chose to utilize a pair of Giant Scale Aerobatic canopies for each of our B-47's. One is for the frame...the other is the
clear plexiglass. Did this so they would have perfect surface to surface contact when cut down to proper sizes.

This requires adding a proper windshield which is either matched up with something already available or from scratch printed
with out 3D printer.

[Flite-Metal]

I tried to email Jim Diamond, tip of the B-47 Assn. spear. He was helpful in pointing me in some positive directions early on
and a subscriber to this thread.

We now turn to everyone viewing this thread asking for your help. If you know this answer or know someone who was a
"B-47 Pilot"...I would like to hear from you ASAP. Below is a photo of an early style canopy and overhead sun shade/curtain
frame. A red circle is drawn around end of the frame to focus your attention on the curtain frame end.

My question is simple. In the center of the circle is what appears to be a light bezel with reflector and lens with a light
bulb in the center. This is simple... Is this an illusion or was there a light in the end of the curtain frame?

[Flite-Metal]

Images previously shown in this post were removed to prevent confusion.

[Flite-Metal]

You rapidly come to realize when I appeared to be all over the place from time to time...in my initial B-47thread "In The Beginning"
The reason should now be obvious...maybe not. If you are building along with us you realize you can not work on any 1 element
or portion of this project for very long or you will burn out... So we across a pond hop by hop, lilly pad by lilly pad until we reach
our goal on the other side.

We now have reached that point in this project when we marry our removable pylon blade, onto which all power management

components are mounted...to the cosmetics of the scale Boeing B-47E and WB-47B.

Remember when this project began it was 1:8.6930 scale. Well friends and neighbors, we have returned to what we originally
assumed and ended up with 1:8.7669 scale. A mere.0739" difference from what we began with 12/10/2009 @ 09:30 PM ;^)

[Flite-Metal]

Remember it is the dims of the power management system that determine the size of the model. Fan yield in # of thrust
is what you multiply the weight of the model by to determine if it is gonna fly. Simple enough isn't it... Below is the XPS
Dynamax Extreme Pro. Its thrust to weight is unparalleled for thrust at takeoff and per the states, the best air speed. I
am not so concerned with air speed...its the AUW at competition air speed I need>

The accepted 1.623 pounds X # of thrust = airframe weight flown properly for competition. Currently XPS produces 26+#
thurst on 15S (65C) @ 34,500 RPM with 168A. In the B-47 this equates to fly an 84.396# airframe for 6.8 minutes at 100%.
This is obviously not going to be our weight, but serves to illustrate thrust figures based on "only" the inboard nacelles with
EDF. In reality we have 90mm in our outboard nacelles and 120mm XPS bifurcated in the inboards.

Because our estimated 45# equates to a 53.32006% load factor. This equals 153.32006% or 10.425764 minutes @ minimum
throttle management.... :^) Throttle management should yield the solid 11 minutes I need



Dynamax with Xtreme Pro 2 motor.



Tommy Cook's Dynamax is the domestically manufactured fan we recommend for superior EDF in anyone's replication of this project.



Below the ICE ESC should be rated at 200 surge for this application, not the ICE 120HV as shown. with 65C 6800's. Note blade
is cut out to accept ESC, batteries, and fan and its motor. All of this is removable from the inboard engine pylon for extremely
easy servicing without having to turn the B-47 over.



ESC is placed behind motor to access greatest amount of cooling air. Retract is a Hobby King electric retract. Nacelle scale
parting lines permit access to components without differing access panels that would otherwise be a static down grade.

[Flite-Metal]

It should be obvious at this point that our pace and range of post topics are going to have a wide range over the entire length
and width of our B-47 airframes.

If posts do not explain what is being shown we recommend you review the "In The Beginning" thread or previous posts within
"In The Middle". This complex build incorporates methods and processes which may be estranged to your skill set simply by the
fact people today are exposed to less and less scratch building techniques. All too often someone refers to plan building as a
scratch building exercise... Obviously there are more than a few differences as witnessed within this scratch building project.

While the ARF and ARC aircraft kits have contributed to growing the number of modelers flying today, they have not exposed
these individuals to baseline building skills. These elements are not complicated, they are documented here-in by references
which can be back-storied online to explain details of the process.

Your feedback is welcome and encouraged. The reason this project was placed within WattFlyer was to show how a scratch
building project moves from consideration to flying overhead. Not understanding something is an everyday occassion and is a
good thing to experience. Not asking questions about something you do not understand is what is bad...for you and your R/C
knowledge base. Try to learn something new, everyday...I do.

There are no greater-thans with respect to competitive flying scale modeling skills, be they building or piloting. Mentoring is a
responsibility and ultimate obligation. What scale modeling skill have you shared today?

[pattern14]

Hi Ed, still following your thread with anticipation and interest. I've actually put the lot onto a storage device and loaded it onto a non internet computor, so I can simply reference it instead of logging in to Wattflyer etc. You also mentioned a couple of scale modeler books some time back now, but I have not been able to source them yet. Either way, its all good. As for the comments on ARF planes and such, it is a frequently bought up subject i.e-scratch vs kit vs arf ( or foam vs balsa, or glo vs electric etc.) Not the thread to go off topic on, but it just seems to be the way of the world. Instant gratification, never enough time, near enough is good enough and so on. As years go by, less and less people scratch or kit build-period. Keep the flag flying

[Flite-Metal]

Pattern,

I understand the constraints of the modern two household income earners and less discretionary time and money to invest in a
modeling project. It is my intention by posting this project within WattFlyer to witness some of the skill sets passed to me by
many who mentored me over the years. Most of this is simple, small steps which created a habit of measuring multiple times in
multiple ways before reaching for a Zona saw or turning a band or scroll saw on.

Everyone's club/flying site is full of resourceful individuals from whom we should learn. Too often I see someone who's shy and
fails to ask about something though it is obvious they found something about someone's model they wanted to learn more about.
If your club does not prescribe to a how-to session at every meeting it might become the bright spot in what too many see as
a boring habit...

My airplane modeling began with stick free flight after electric trains and wood/plastic ship building with my father ran into the
demands on his time with the boom times of the early 50's. He'd catch me trying something in a way I should not. With a kind
word of encouragement I was quickly off to the next step in whatever it was I was building from what I had seen in a modeling
magazine or in Popular Science/Mechanics.

Yes, people build from those one or two page model plans you find in magazines. Gee I wonder if Sam Wright will have some of
those gems in his new Scale Aviatior International?

I don't recall what I may have referenced previously...however there are two books by Harry Higley and one by Rich Uravitch
that should be in everyone's shop...

Harry Higley's "There Are No Secrets" and "Foaming Around".

[Flite-Metal]

Sam asked one of the CAD people at work if he could print something for us. As it turned out the person was extremely
interested in our B-47 project and we were off...to the races...well as it turned out, its more like we are off...

The drawing below is the wing at 1:1 which equates to 158.7783 in total span. Remember what I said about 4 decimal
places for all my dims...well here's a perfect example of why. The person printing the files rounded down to 8.25" from
a drawing defined with 8.2830" as the control image on every drawing.

When printing there are many variables. In an air conditioned replication environment everything is stable. A computer
drawing file is always going to be "off" unless composed in a common software created explicitly for design and printing.
A control image is placed in each drawing to permit the person printing to normalize the drawing. For example each of
our drawings has a control image measuring 8.2830" long.

If printed properly the control image will print at 8.283x with x being shrinkage due to the xerographic process of printing.
Instead of measuring and adjusting for differential...the guy printing all our drawings rounded the 8.2830" to 8.25" so we
ended up with a w/s differential of 1.0283"... :^(



We will normalize Sam's copy so he can lay out the new flap system he designed.

Dave, I suppose this explains why I use four decimal places on my design work...

[Flite-Metal]

We have reviewed our -.0064763:1" printed image factor as a result of the printer operator's not following convention...

In reality the reason the design was printed at this time was for Sam D' Sham to use in building the Pharaoh's new flippers.
This will work fine with its span not greatly effected by the error for using as the flap bay outline.

Below you see our "tan" flap bay, which is also a removable composite plate onto which carbon fiber flap rails are mounted.
The plate is attached to composite strips embedded in the roof of the wing flap bay cut out. Multiple embedded strips with
threaded screws sitting at right angles to the top wing skin sit across the flap bay span to provide rear attachment of plate.

Forward edge of flap plate has right angle vertical strip drilled with holes through which captive threaded screws mounted to
rear wing spar protrude to provide forward mounting of flap plate.

[Flite-Metal]

Below I will provide the baselines of our flaps and describe their sections as Sam has redesigned them. He is constructing and
assembling our flap system as I write. Sam will take photos along the way as he did during his first flap design.



The flap plate overall footprint...sans lightning holes. Flap plate is screwed to wing enabling maintenance outside the B-47.



Note wing taper compared to the red reference point.


Outboard Plate Inboard Plate

[Flite-Metal]

Below are the common grades of resin impreg materials with their industry/Mil Spec. names as well
as commonly misused names. Often people think everything that looks like thick resin impreg fiber
glass cloth is G-10 when as you can see below..that is clearly not the case.

G-11: Mil-I-24768/3 --Glass cloth with epoxy resin. Higher heat resistance then G-10.

G-10/FR-4: Mil-I-24768/27 --Flame retarded glass epoxy laminate.

G-9: Mil-I-24768/1 --Glass cloth impregnated with a melamine resin.

G-7: Mil-I-24768/17 --Glass cloth impregnated with a silicone resin. Flame and arc resistant.

G-5: Mil-I-24768/8 Glass cloth with melamine resin binder. Flame and arc resistant.

G-3: Mil-I-24768/18 --Glass cloth with phenolic resin. Not flame retardant.

FR-5: Mil-I-24768/28 --Glass cloth with a melamine resin. Flame and arc resistant.

XXX: Mil-I-24768/10 --Bleached Kraft paper impregnated with a phenolic resin.

XX: Mil-I-24768/11 --Bleached or unbleached paper impregnated with phenolic resin.

X: Mil-I-24768/12 --Unbleached Kraft paper with a phenolic resin.

LE: Mil-I-24768/13 --Electrical grade, fine weave cotton cloth impregnated with a phenolic resin.

CE: Mil-I-24768/14 --Electrical grade cotton cloth impregnated with a phenolic resin.

Linen: Mil-I-24768/15 --Fine weave cotton cloth impregnated with a phenolic resin.

Canvas: Mil-I-24768/16 --Cotton cloth impregnated with a phenolic resin.

Polyimide: --Glass reinforced kerimid 601 bonded laminate.

N-1: Nylon Reinforced Phenolic
The phenolic materials in blue above have proven themselves to make good formers capable of being cut with
scissors, and when touched by a hot wire the edge, proves to survive for the seconds required to hotwire.

Paper Reinforced Phenolic:

These grades are composed of a paper base impregnated with a phenolic resin binder.

Grade X has the lowest resin content for good impact strength (but less than the fabric grades).

Grade XX has increased resin content. This decreases the impact strength, but increases electrical properties
and reduces moisture absorption.

Grade XXX contains the highest resin content and therefore the best electrical properties of the paper grades.
It also has minimum cold flaw characteristics.

[Flite-Metal]

I'm currently looking for a T.O. 1B-47E-2-1 in digital form...in case you have one... :^)

[Flite-Metal]

Flap cycle: Flap plate is shown sans lightening holes. Holes are cut after complete installation of the flap mechanism to assure
everything aligns properly during the assembly process.



Outside flap functions as an aileron through the first 20% of its travel. This is coupled via transmitter and offset via the two
onboard gyros installed to correct Dutch Roll during final approach and offset cross wind up to X mph (TBD). There is 70:30
aileron differential on B-47's.

To offset the Dutch Roll and provide heading I am using an approach parachute. This will pull the nose to center thereby it
reduces the yaw aspect of the natural Dutch Roll accompanying the B-47's swept wing and "too clean" surface with minimum
parasitic drag. Approach chute enables throttle to maintain heading while maintaining our required level landing attitude.

[Flite-Metal]

Sam needs the air foil plots for his hot wire flap set-up so I went ahead and did the aileron as well.


Note the Frese aileron with cuffed leading edge socket. This is exposed all the way to the wing tip cap. At this scale
the wingtip is 10.5280" front to rear. Hinge point is above center to faciliate 70/30 aileron differential. I show the two
wing tip caps below. Note, they are shown by BuNo and build date.

Note: Rounded over aileron rotation point and wing cuff.

[Flite-Metal]

Sam ordered Dow Highload 60© from our local distributor today. They are cutting the billet down to a pair of 24"x48"x3" from its
original 96" length. His focus is on hot wiring the flap set-up this week. With good fortune and no opps factors we should have
film at "11"...or was that by the 11th? Ahhhh whats a couple of weeks at this point :^)By



Considering this comparison we rapidly begin to draw a conclusion on what is going to be used for the fuselage center section.
Can you see where we are headed? Here is a hint: Dow Surfboard Foam© weighs 10% more than Dow Highload 60©. What do
you think we should use. Dow Highload 60© or Dow Surfboard Foam©?