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Ladies and Gentlemen!

Children of all ages!

Welcome to the greatest.....well, um to a pretty good build  of a pretty big thing.

To set the stage;

A friend of mine does large scale RC aircraft models.

His latest completion was a 1/9th scale B-17G representing Nine-O-Nine. a Fortress that is still flying.


The model was brilliant with something over 5000 rivets, chipped paint, and some amazing weathering applied to the exterior.

He likes to do scale events and felt that his model still lacked something.

Like an interior.


He had a ball turret 3d printed and realized that he couldn't finish it to his own satisfaction.

So, I got it.




I immediately started cutting it apart along the lines of the real turrets castings.

Much priming and sanding got me a nice clean interior surface to begin from.


Ammo boxes were cut out of balsa and skinned with .010 sheet styrene.


The gun control unit was made up out of the usual bits of plastic.


It took a lot of digging to figure out what this thing actually looked like.

Not a lot of pictures of the insides of ball turrets.

But I am persistent...


This all took a while and I have a lot more photos to show but I need to knock off to-night

The good thing about this thread is that I actually finished the build so that you know there will definitely be some sort of conclusion to all this...


I can see where I'll have to learn how to reset pic sizes.....

Edited by Tzulscha
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1/9 scale Fortress????


My gods!!


Looking forward to seeing how big the 17 is!


Ball turret is looking great too! Any other plans for interior sections? Bomb Aim sight etc.?

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1/9 is a fairly practical size for a R/C bomber. My first B-17 was 1/10 scale, just over 10 feet span. A 1/6 scale version followed, but at over seventeen feet span, twelve and a half feet long and 140 pounds take off weight, it was a huge monster to transport and I ended up building a 12 x 6 x 3 feet trailer to transport it. 

1/9 scale puts it at 11.5 feet span which is manageable for every day flying at a club field. The turret looks good and being close to the C of G, a little weight here isn't too much of a worry.

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I have done the Ball turret,  bombsight, nose turret sight and control yoke. Cockpit,  upper turret and the radio compartment for this airplane.

Pilot, co-pilot, radio operator and top turret gunner as well.



I plan on posting my construction photos for all of these components

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A nice project but would have been nice to see more flying and less talking! Shame to have spent 6000 hours, all that work and then paint exhaust streaks from the wing vents - a common mistake that was also made on the "Memphis Belle" film aircraft in 1989!!

Did you get plenty of photos of your detail work?

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 A few more pix of the plane, just to keep you guys amused until I get some more build shots up.











If you look REALLY close, you can even see some of my work here!  :lol:

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I feel like I'm making a bit of a hash out of this presentation.

I did this work a while ago and my photos are poorly organized.

I think I will try the "Show a few sub assemblies at a time." approach.



The Sperry ball turret found on most B-17s is a series of aluminium castings, bolted together and with all the other bits attached to the castings


Right and left outer castings. Gun mounts in place and the shell ejection chutes are being made of balsa shapes covered in .010 sheet styrene.

The .50 cal were also 3d printed and, except for trying to get rid of all the print lines, not bad.

The printed barrels were unusable and I got hold of some nice machined barrels



Some test assembly of various components.

I was working almost entirely from photos on this build and I had a terrible time getting everything to fit just right.


Starting to see what a gunner would see.

It's all crammed into this little ball. Visibility would have been pretty bad.

Later turrets had an external ammo supply, but with this version there are two huge ammo boxes taking up nearly 20% of the interior space by themselves.


The bits needed to make sure you are not just spraying and praying down there.

It seems to be a fairly normal gunsight except that it all gets mounted upside down.


Balsa again for the basic shape covered in card.

A few bits of wire as a guard and a bit of black primer so I can see what I have screwed up.

Just one more blurry picture to-night



It gets better...  (I hope :fraidnot:)

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Were all the parts rigidly glued?


In cockpits, when I've been mounting larger detail pieces, I've often used silicone rubber to glue with, as it gives a little vibration protection in R/C models. Perhaps it's not such an issue on electric powered models, but there's still landing loads and vibrations from grass runways.

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4 hours ago, Army_Air_Force said:

Were all the parts rigidly glued?

Eveything inside the turret was mounted as rigidly and solidly as I could make it without screws and bolts.

I wanted to make darn sure nothing would shake loose because once it was closed up it was gonna be a bear to fix anything inside without cracking the shell.

The complete turret is however, removable from the plane and carried in a shock mounted support very close to what the real thing used.

It seems to have survived very well so far although a foam dummy turret was made after a slightly rough landing scraped up the bottom of the scale turret.

Now the scale turret is used mostly for displays.


More pictures in a bit!

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Okay Here are few more bits to look at if you don't mind spending the time.


Colour certainly makes things a bit easier to see don't they.

Wow the size of the image sure pops out the flaws! Yikes! :confused:

Okay, steering and control unit, the steering yoke has not yet been installed.






Ammo boxes. Upside down obviously.

Nuts and bolts are HO scale train gubbins





A bit of armour plate for our gunner to sit on. The real stuff looked like 10-15mm thick.

The gadget on the right with the toothpick sticking out of it is the oxygen regulator.

The silver box in the middle is the control for the electrically heated flight suit.

I have absolutely no idea what the thingie on the left is.

I'd be grateful if someone could tell me.





A bit better shot of the side castings with the gun mounts and drive gears in place.



A look at the latches holding the gunners escape hatch shut.

The pulleys on either side of the hatch are for the gun cocking cables.





An upside down shot of the front of the shell.

The little gadget is part of the turret detente. There is a pin on the outside of the turret that keeps the guns from over elevating and shooting holes in your own plane.

Pilots hate that sort of thing.

The printed model had got the top windows wrong and I had to fill with card stock.

It looks much nicer on the outside.

Inside gets hidden by ammo boxes.



A few more bits and bobs and then some actual assembly stuff!

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On 6/14/2019 at 3:34 AM, Tzulscha said:

I feel like I'm making a bit of a hash out of this presentation.

Nonsense dear fellow.

Talk with your own voice and in whatever order you feel like. Work of this quality will always have avid followers. Count me in! 😄

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I'm following up and catching the bits that he misses. 

There should be dozens of these made. Real display items for the den.

Keep the pictures coming, please.

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Thanks fellas.

I appreciate your comments.

I'd also like to thank Pete for putting me on to Imgur.

The hosting site I was using before was a pain in the tucchus to use.

 I have accumulated vast numbers of photos over the years, but it was too difficult to just casually post them.

So I've been drooling on your stuff instead of showing my own off.


So, blame Pete for all the crap I'm about to start posting!  :thanks:

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In an effort to keep up interest I have found a few more online shots.

Not a great view through the dome but you can just make out the bomb-sight

and the turret control yoke.

I'll do more pix of the nose compartment when I get done with the turret stuff.



The pilot/copilot were done by Best Pilots models who do some superb figures for your RC models.

I reposed them and changed the paint a little but they are mostly out of the box.





Revving up for a take off.

Looks pretty realistic doesn't it?



Here are the details from Mike...

"The B-17 is a 1/9th scale Wing Span kit. The span is 138 inches and the fuselage is 99 inches long. Weight is 65 pounds. The model is powered by four Hacker A60 electric motors and ESC's. Being all electric each motor is individually controlled so that the outboard motors provide differential thrust to off set the yaw inherent in a model with a large vertical stabilizer and tail wheel.

Four Thunder Power 4s 7700mah batteries are used wired in two 8s circuits. Each circuit draws about 5500 watts at full throttle using Master Air Screw 16X10 three bladed propellers cut down to scale.

The flying pictures were taken on a day with 15 mph steady cross winds and occasional gusts to 30 mph. The airplane flies like a trainer.

The model also has pneumatically powered individual brakes to provide better steering and additional yaw control at taxi speeds. Just like the real B-17,  you can lock up one brake and rev up the opposing outboard motor to make a scale turn.

 I use an 18 channel Spektrum Transmitter, eleven JR servo's and JR gyro's. The model is finished using catalyzed urethane primer and aluminum color coat. Model Master enamel is used for the top colors and is is wet sanded and tape pulled to provide a weathered appearance. About 250.000 Pro Mark dry transfer rivets and fasteners are used for added eye candy under the top coat paint. The model has about 6000 hours so far and was built from the inside out so that significant interior detail could be included in hard to get to spaces."

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Amazing work there matey. Some of those photos could be mistaken for the real deal.

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Thank you Gorby. High praise!

Seldom achieved however.


Here are a few more attempts.


Another shot of our seat from underneath.

Oxy hose is solder wrapped in solder, covered in latex and painted with acrylics.

A bit of a wash to pop the detail and it's ready to mount!.

Also in the picture is probably the best shot I have of the gun sight and one of the ammo chutes.




The control gear looks MUCH better with a lick of paint.

If I could only learn to take a decent photo...




Electrical box getting wired up. Gang plugs on armoured cables.

Switches and wingnuts  just in case you need to open the box wearing gloves I expect.




Getting things mounted.

Heelplates in place  (I think the left one is the gun safety switch)

The red handle is the gun charging handle, which will be hooked to the gun by a cable.

Oxy regulator and gauge are in and (mostly) connected.



Oh! a seatbelt.

Must have one of those in case you fall out.

Although.. you don't actually need to undo your belt to get out of the turret.




When you get all these bits  jammed in it sort of looks like this.




It's getting there, I'll have some more in a bit.


Thanks for looking!

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Just a few more and it will all get closed up




On top of the turret is an inspection port.

Which I almost missed until it was too late



Looking in through the hatch right side.

Padding for our gunner was cut from the fabric of an old mattress that I liked the patterning on.

Most of the gunners padding came from a back-pack type parachute.

It would be really easy to get out of this thing in an emergency.

You don't even have to undo your lapstrap.

Just release the two catches on the hatch and fall out backwards.

Provided the turret isn't jammed in an odd position.



aaand on the left.

All the interior masking has been removed.

This is the last test fit before we close it all up


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All right, got a few more turret pictures and then I'll dredge up some cockpit shots.

I have tons of photos that I've wanted to bore people with for ages. 

People look askance when you wander up to them offering to show off your ball turret in my experience.


One last before we close it up.

Not an angle you usually see.




Tamiya lacquer Neutral grey over Tamiya Silver leaf.

All the masking peeled off. Shiny!






With the hatch open.




The business end



And mounted into it's support frame.




Tune in next time and let me show you my instrument panel.    :please:

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Well there may be some more pix of the turret but I've probably lost them somewhere in the depths of some indistinguishable folder among hundred of the flippin' things.

Stupid computer (Oh yes, that's right blame the computer.)



Anyway here are a few bits to dress up the cockpit.


Some of those wheelie thing that pilots use to steer with.

(and a whole bunch of clutter)



And from the front.

I eventually even managed to find some Boeing badges for them but I don't think I have any pictures



To make the instrument panel I sized a drawing and laid everything out directly from that.

Bits of tubing for the instrument rings, sanded down and reamed to size.

Strip stock in little bits to make everything else







And the bit on the right side




Center console and throttle quadrant.

One of the details that drove me crazy trying to figure out was the little box on each side that had a round cover with what looked like a knob on it.

Then I found it.

It's the ashtray from a 1939 Ford.

They took the assembly, made a bracket for it and riveted one on each side of the throttle quadrant.

Smoke 'em if ya got 'em boys!




From the front




And a little colour to finish off for the night.



Placards on, instruments in place.

The instruments were computer generated by some company that I can't remember the name of that does such things to any scale you like.

The red and yellow lines surrounding the engine instruments is .3mm  pinstriping tape




I hope that was interesting.

Building this thing makes me think crazy things like how about  a 1/1 instrument panel?

A bit of plywood, a bit of paint. 

How hard could it be right?

Ooh if I could just find the right toggle switches....




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And now he shows me something else I want for the mancave. I mean, a B-17 instrument panel! How could you not want one?

Back when I worked on them, RAF Puma Helicopters had ashtrays fitted. One of our Pilots regularly left his smokes and Zippo in the Cockpit.

Toggle switches? They are out there somewhere. Boxes of them!


Yes, I am an adult (apparently) of above the age of consent. Please show me your photographs of Plane Porn.


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I found some shots of the turret mounted in its place.






And some shots of the finished instrument panel in the cockpit.





I noticed that while it's sitting on the runway with people standing over it, the plane doesn't look all that big.

Sit it on the dining room table however....


Your wife will immediately start to wonder loudly when you are going to move it.

(Not my dining room btw, I don't have that much space.)


Now we need to fill up some of this space.


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Time for the bombardiers toys.

I am fortunate in that we have the Kalamazoo Airzoo not far from where I live and they have the aiming head for a Norden bombsight on display.

I am using my lovely assistant Carey here to help with scale.



Unfortunately they don't have the rest of it so it was off to the internet to figure out what the control box looks like.

A slug of epoxy resin from a failed casting turned into a cylinder provides a starting point to mount all the other bits on.






From there it was just a case of sticking on all the little fiddly bits eh?



The bombsight head looks like an incredibly complicated shape and it was difficult to know where to start.

The gyroscope casing was the place.

I found a couple of steel ball bearings that were just the right size and vacuum formed a shell over them.




The rest of the casing was just attatching tubing of various sizes, adding flanges and LOTS of putty to smooth it all together.

The black paint is so that I could see the shapes properly



Some more gubbins for all the knobs and switches and what not.

A quarter for scale.



And we have something that can hardly be seen through the nose bowl!




Next time I'll have the chin turret controls and sighting mechanism.


Thanks for looking!



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Just few bits today.

I'll have to upload some more stuff to Imgur.



Steering control for the chin guns


Control head with triggers and safeties.





The locking mechanism on the base.



Lousy picture but possibly something helpful in the shot.

My favourite clamp is a standard spring type clothespin with the jaws reversed in the spring.

You get some nice long fingers that you can shape anyway you like.

I have them with slots and grooves and notches.

My lamps and bench are festooned with these thing.

Cheap too!



A little bit of colour and it's just about ready to mount.

The little silver bits on the sides of the grips are your safety switches.

Just needs its placards. (Which,as it turned out, you can't even see. Figures.)




Okay, I'll get some more shots when I get the images uploaded.

Comments, criticisms and bad jokes are all welcome!


Thanks for looking!

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