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#4516712 - 04/16/20 04:34 PM FN5 turrets for RC Wellington 1:4.5  
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I've been working on a pair of model FN5 turrets for an RC Wellington, which are designed to have FPV cameras to take footage from within the turrets in flight, much like what RoboBiggles has done on youtube. The turrets feature:

Fully working pneumatically elevated gun-cradle and guns
Model Brownings with working cocking mechanism and liftable top cover
Fully working miniature collimating Mk III gun-sight with automatic reticule dimming in low light
A spotlight, overhead lamp, 3 Bendix signalling lamps and a "panic-light" - all work.
Ammunition tanks and various chutes for feed of rounds and expended cases and links
600 parts per turret, plus a similar number of M1 machine screws, washers and nuts etc, hand-tapped into the nylon parts. Virtually no glue anywhere.
Provision for servo operated traverse
Fully glazed cupolas with correctly shaped compound curvatures (in progress)
Fully operable rotary ventilators (not yet fitted)
Openable doors with working latching mechanisms
Hand-dyed correctly coloured silk-covered cosmetic wiring
Correct mechanical linkages to slave the gunsight to remain parallel to the guns.

My youtube channel can be found by searching for Fidd88 or via these embedded films:

1st test of elevation mechanism


Collimating gunsight


Film of stills taken during construction


Exhibiting the turrets recently at Brooklands


If you have questions or would like to look into sourcing a kit, or commission turret builds, please don't hesitate to ask.

Last edited by Fidd; 04/16/20 04:50 PM.
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#4516777 - 04/16/20 10:45 PM Re: FN5 turrets for RC Wellington 1:4.5 [Re: Fidd]  
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No words... eek

This is way to crazy to imagine flying...

#4516786 - 04/17/20 12:13 AM Re: FN5 turrets for RC Wellington 1:4.5 [Re: Fidd]  
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hehe, cheers, and thanks for taking the time to reply. There's a load more films on my channel documenting the build, successes and failures. I taught myself CAD and 3d printing at the beginning of the build having not made a model for 40 years. I'm considering making it, in slightly simplified form, as a kit of 3d printed parts, in scales from 1:3 to around 1:6 for RC modellers or model-makers who fancy a different sort of a model. I'm currently working on the cupola windows, so hope to get the vac-forming done once CV19 falls over.

#4516808 - 04/17/20 04:18 AM Re: FN5 turrets for RC Wellington 1:4.5 [Re: RSColonel_131st]  
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Attached are a load of stills taken during the build. The yellow structure is a rotatable jig, to allow work on any aspect of the fuselage or wing without having to take it out of the workshop to turn it around. The CAD picture of the geodetics shows the changes that need to be made to fabricate this even with small pop-rivets. A prototype shape will be made this year before construction proper of the airframe begins.

Attached Files swturretbw.jpgwire1.jpgdirt4.jpgdirt3.jpgdirt5.jpgdirt1.jpg025.jpg45.jpgfitted pipes stack600.jpg600 pipper noack.jpg29.jpg1.jpgjig.jpglma4.jpgarms.jpg
Last edited by Fidd; 04/17/20 04:20 AM.
#4516809 - 04/17/20 04:34 AM Re: FN5 turrets for RC Wellington 1:4.5 [Re: Fidd]  
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And some more recent stills, in black and white

Attached Files 20200323_144613BW.jpg20200323_144724BW.jpg20200323_144909BW.jpg20200323_145138BW.jpg20200323_145157BW.jpg20200323_145254BW.jpg20200323_145716BW.jpg20200323_150014BW.jpgP1070717bw.jpgP1070718BW.jpg
#4516822 - 04/17/20 09:00 AM Re: FN5 turrets for RC Wellington 1:4.5 [Re: Fidd]  
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Naunton Beauchamp Worcestershi...
Bloody marvellous!
Are you going to go on and finish the rest of the aircraft now? smile



#4516827 - 04/17/20 09:49 AM Re: FN5 turrets for RC Wellington 1:4.5 [Re: Fidd]  
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As soon as the turrets are complete, they'll be mothballed until the airframe has a few flights under it's belt, with fairings and ballast standing in for the turrets. Before the fuselage can be built, I need to fabricate some test-structures for fatigue and vibration issues. The intention is to build a simple bending machine with a chain of interlocking spacers within the geodetic channel, so that as it's bent, the cross-section can't collapse.

Once all that little lot is squared away, the build proper can commence, probably around the middle of next year. I'm anticipating the fuselage being a fairly rapid build, as there are essentially only two joint types involved in 99% of all the joints, and it's largely rivetted. The wings are rather more complicated, so they'll be built after the fuselage, applying lessons learned during that phase of the build. The wings will separate outboard of the nacelles for transport.

The turrets are predominantly built from 3d printed SLS nylon, and are largely screwed together. This meant a great deal of work hand-tapping threads with M1 and M1.6 taps, but reaped great benefits in that I could back out of a build sequence to an earlier point in the assembly, without having to break apart parts that had been glued; and as the build sequence was so complicated in terms of getting tools onto nuts or machine-screws, this was an absolute lifesaver. It was a lot like building a clock - with 3 foot long screw-drivers!

The eventual aim is to simplify the design of the turret, and offer it as a kit, printed to any scale between around 1:3 and 1:10 or thereabouts for RC modellers to incorporate in their aircraft, but possibly without the driven elevation and lights etc.

Last edited by Fidd; 04/17/20 09:53 AM.
#4516852 - 04/17/20 11:55 AM Re: FN5 turrets for RC Wellington 1:4.5 [Re: Fidd]  
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When I first saw this thread I just scrolled through the first post and looked at the video stills, didn't read any text. I thought I was looking at the restoration of an actual turret. Amazing work. Welcome to the forum Fidd


"In the vast library of socialist books, there’s not a single volume on how to create wealth, only how to take and “redistribute” it.” - David Horowitz
#4516862 - 04/17/20 12:22 PM Re: FN5 turrets for RC Wellington 1:4.5 [Re: F4UDash4]  
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Originally Posted by F4UDash4
When I first saw this thread I just scrolled through the first post and looked at the video stills, didn't read any text. I thought I was looking at the restoration of an actual turret. Amazing work. Welcome to the forum Fidd


Thanks for the welcome. It's been a fascinating project, as virtually no technical drawings of Frazer Nash turrets exist, and book illustrations tend to have errors in the geometry, so whilst they appear to be an assembly drawing, if built as drawn, things collide or do not move properly. This was a particular problem with drawing the cupola, as it needs to appear to be the correct shape, but it's also designed to allow free movement of parts such as the gun-sight sighting bar which only just miss colliding with the underside of the Perspex window panels.

Fortunately, Mark Evans gave me his CAD drawings of some components he'd recovered from wrecked aircraft, which helped enormously, even if I had to change some dimensions to optimise it for fabrication via 3d printing/screws.

I'm also working on an FN4 and FN25 turrets, which James from Newcastle very kindly sent me as .obj drawings. Pics attached. Also pictured is the scale 250lb GP "bomb", which I may develop. It uses a CO2 cannister to blow a cloud of dust and low-energy "debris" in the form of compressed-sponge within the casing, which comes apart on impact once the cannister is punctured. I need to rework this to bring the cannister into the nose, and have it struck from behind by a firing pin which is free to move towards it when the nose is suddenly decelerated by the ground. This will help the C of G and reduce the overall weight.

Attached Files fn4inprog.jpgfn25.jpg250lber.jpg
#4517007 - 04/18/20 12:46 AM Re: FN5 turrets for RC Wellington 1:4.5 [Re: Fidd]  
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Welcome Fidd, you're a bloody typical nutter pom aint ya geezer biggrin

Your work is stunning mate, i imagine it will end up being quite the hit once you roll out the completed project out. Does it stem from an interest in WW2 aircraft and rc planes or did you just decide you had to have a massive Wimpy that you could call your own?





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#4517057 - 04/18/20 12:58 PM Re: FN5 turrets for RC Wellington 1:4.5 [Re: Fidd]  
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My father was in the RAF towards the end of the war, hence the interest. He's long since dead, but I still have his notebooks and pre-war books extolling the virtues of the RAF's new aircraft, the Blenheim, Hampden and Wellington. Of these, the Wimpy was his favourite. Like him, I'm something of an amateur self-taught engineer and inventor - for fun really. My aunt still laughs, 80 years on, at the memory of his home-made mains-powered wasp-trap. His experiments extended in July of 1940 aged 17 or so, to making his own gun-powder and devising what nowadays we'd call IED's. In those days it was called "High spirits", and given it was widely thought that Jerry would be invading within weeks, tacitly approved of, until desire out-ran performance, and a particularly enthusiastic bomb was detonated on the family Anderson which set off the local sirens. A collision with authority followed, he and my uncle were adjured "to join-up, before someone gets hurt"!

So, about 7 years ago I was looking into making model Airship, until I discovered why very few have achieved it - and learned of Barnes Wallace's use of geodetics in airship design. That led me to the Wellington. I'm much more interested in replicating the geodetic construction than the flying model, so I've no interest in a balsa model which externally resembles a Wellington, but lots in a miniature one, whether it flies or not; although the intention is for it to fly. So for the last 5 years I've been researching the air-frame, doing tons of CAD drawing on both the airframe and turrets, and building the turrets.

Attached is an early experiment of my father's at grans house in 1940, and one of early drawings relating the known internal bulkhead (silver coloured) dimensions within the Wellington to interpolate the cross-section of the airframe at any given station (wooden appearance) - all 97 of them! This is a first step to defining the required curvatures of each geodetic channel over the shape, the geodetic paths being angled at 45 degrees to both lateral and longitudinal lines.

Attached Files bw1.jpgfueslage v38halfleft.jpg
Last edited by Fidd; 04/18/20 03:43 PM.
#4517085 - 04/18/20 04:47 PM Re: FN5 turrets for RC Wellington 1:4.5 [Re: Fidd]  
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Naunton Beauchamp Worcestershi...
Causing an explosion in July 1940? I should think "A collision with authority followed" is somewhat of an understatement! Great anecdote though.
Surprised that with his experimental and innovative leanings he didn't get the tap on the shoulder to join one of the 'Funny Outfits' e.g. the GHQ Auxiliary Units. Perhaps he was too young! What did he do in the RAF?



#4517087 - 04/18/20 05:08 PM Re: FN5 turrets for RC Wellington 1:4.5 [Re: BD-123]  
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As my uncle related it (he claimed to be "led astray by bad companions!") the magistrate was finding it hard to keep a suitably serious expression as they were officially reprimanded, and as their efforts were wholly in the interests of defending the country should Jerry have got across the Channel, they did have the sympathy of the court, and were spared convictions, if they joined up without delay.

My uncle joined the Royal Armoured Corps, and was part of an independant tank brigade supporting infantry. He fought from D+3 until the end of the war, and survived (I know not how!) commanding Shermans and later Crusader, towing 17 pdr's. (the latter posting to a safer billet after his 3rd bailing-out from a burning Sherman.)

Dad was eventually trained up as a fighter-pilot at 1BFTS Terrel, Texas, and arrived back in Europe just as the war against Germany was in its final throes. He, and hundreds like him, were then slated to join in what everyone thoughts was going be the invasion of Japan, but just before he was sent out, that war finished too! And in '47 he was demobbed, and never flew again until the mid 1950's, when he and a mate from Terrel days hired a light aircraft for a day. It's my considered (and professional) opinion that they must have frightened themselves half to death, as neither of them ever flew again!

As for myself, I took up gliding for fun, obtaining a "Silver C" then did a PPL on powered aircraft, before eventually going going commercial and qualifying as an ATPL/IR QFI rated to teach the commercial flight test syllabus, instructing for some years until a car-accident put-paid to flying. All I'm allowed to fly these days is "into rages"!

So now I potter in the shed all summer, and do CAD work for the project all winter. Yesterday I attached some flanges to the expended case chutes, and reinforcements to the side of same facing the gunner. In both cases it was to widen the apparent width of the chutes which are a little too narrow.


Attached Files flanges2.jpgflanges1.jpgflanges3.jpg
Last edited by Fidd; 04/18/20 05:21 PM.
#4517140 - 04/19/20 01:30 AM Re: FN5 turrets for RC Wellington 1:4.5 [Re: Fidd]  
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Yep, a whole family of very British nutters! Great read Fidd and that picture is fantastic. I believe the geodetic construction of the wellibag also lead to its great strength, was it because it was a time consuming build time and skilled labour that it didn't factor into more aircraft or was it simply overtaken by more modern building materials/designs?


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#4517145 - 04/19/20 02:54 AM Re: FN5 turrets for RC Wellington 1:4.5 [Re: Fidd]  
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It's really interesting that you've asked that question. As an amateur engineer and military history nut, I've long had an interest in looking at old technologies, and seeing if they are applicable in new ways to modern problems. My burgeoning knowledge of geodetic aircraft design made me reflect on what it was which killed the technology stone-dead in 1945. Geodetics are a phenomenally efficient solution from an engineering point of view, as they have (roughly speaking) 3/4 of the weight, and 130% of the "usable internal space" of a comparable aircraft type built in semi-monocoque stressed skin fabrication. For a bomber that means greater range, greater speed, more disposable payload, and better defense, as you can more easily take the weight of defensive turrets.

Relative to the 2 other Bomber Command types of circa 1937, the "Hampden" and "Whitely", it out-performed both by a significant amount. It also shared a virtue with the "Hurricane", in that largely unskilled labour could be used to effect repairs of damage to the airframe, whereas stressed-skin aircraft such as the Spitfire (and all other RAF bombers) generally required factory-repairs. This virtue led to both Hurricanes and Wellingtons serving in the theatres far away, where the ability to effect local repairs was important at the end of long supply-lines. Simplicity of design can be a real strategically important consideration. The Sherman and T34 tanks had similar properties. Furthermore, geodetics proved quite excellent at withstanding hits from cannon-armed fighters or flak, that would assuredly have destroyed a stressed-skin aircraft.

I digress. I realised that geodetics were killed by the advent of the jet engine. As the structure flexes, it has to have a flexible covering, ie doped-fabric. Such fabric cannot endure the speeds of jet-aircraft. (Indeed many Wellingtons returned with considerable fabric stripped from fuselages and even tail-planes by diving beyond VNE to get away from being coned by searchlights. So studying this, I eventually twigged that if one considered cargo-carrying "drones", then this "aircraft" type would be ideal for building using wartime geodetics, as it was safely back in the speed range where none of the disadvantages of geodetics arose.
To that end, I devised a method of making carbon-fibre geodetics using a two-part extruded silicone mould, which was encased in a tube of polythene, sealed at both ends, and then infused under vacuum with resin. This was then pinned into place over a 3d form of the required shape, and cured in situ. When demoulded, this gave a very satisfactory cross-section of the wartime geodetic channel, at scale. The results were very encouraging, with 33mm of the carbon-fibre weighing a single gramme. However, the failure rate was too high, and I lacked the experience to solve the issues, furthermore, the moulds I'd made were too stiff - I should have used an aerated silicone extrusion - so I abandoned this method in favour of extruded alloy, which was a safer bet from numerous points of view.

Incidentally, the Wellington required little skilled labour in fabrication. There are 30 or so geodetic "panels" which made up the wings and fuselage. All the members of these were formed from strip alloy, progressively curved and folded on a specialist mechanically programmable machine (Still in service in 1969 making parts for "Concorde"!). Small engineering firms all over the country were shipped basic jigs, into which the correct members were placed and rivetted and bolted together. These panels were then sent to Brooklands, Broughton and Chester, where the finished panels were brought together to build the aircraft. This allowed for a bomber to be assembled in just over 24 hours!

I attach some old pictures of the carbon-fibre geodetic channel I made, sitting on top of actual Wellington geodetics, and a few shewing the principle of the two part mould.



Attached Files 33.jpg39.jpg36.jpg37.jpg35.jpg
Last edited by Fidd; 04/19/20 03:08 AM.
#4517157 - 04/19/20 06:48 AM Re: FN5 turrets for RC Wellington 1:4.5 [Re: Fidd]  
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Super interesting stuff, cheers! The problem solving and engineering etc that go into aircraft fascinate me. Seeing them go from a quick sketch or an idea to a flying machine still has me shaking my head sometimes. Even the reverse engineering used in some aircraft, looking at you Russia, is a great subject.


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#4517165 - 04/19/20 09:44 AM Re: FN5 turrets for RC Wellington 1:4.5 [Re: Fidd]  
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I'm sure you are familiar with this footage Fidd, building a Wimpy in a weekend.

I have seen examples of the geodesic framework in a couple of the quirky little museums around here (Worcestershire)
Stratford Armoury
Wellington Aviation Museum
And Cosford of course.
Fascinating thread; thanks for taking the time to post here.



#4517167 - 04/19/20 10:04 AM Re: FN5 turrets for RC Wellington 1:4.5 [Re: Fidd]  
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Very good work there Fidd interesting to see it.

As a young kid when source literature was not so censored, recipes for black powder were quite easy to get a hold of which lead to various experiments in making it and blowing up Airfix kits in the back garden, Ahh those were the days biggrin

While out hill walking looking for a wellington that crashed near the north coast of Scotland we came across what was left of it, really only a shallow pool with lots of rusty metal and pieces of geodesic scattered on top of the hill. Seeing the clothing and shoes in the water brought it home that men had lost their lives flying this aircraft.

It is a great pity that there are no flying survivors of the Wellington, so it is with great interest I look forward to seeing yours take to the sky.


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#4517196 - 04/19/20 02:03 PM Re: FN5 turrets for RC Wellington 1:4.5 [Re: Fidd]  
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It'll be a decade or so before this one flies, I would think, by the time the airframe is all built, wiring looms and servo's and linkages, fuel tanks and pumping system, and half a hundred other things, all built and installed. But for me, it's "the journey rather than the destination" which is fun. There's just a never-ending series of problems to address and overcome - or side-step! - to make progress. I am really looking forwards to moving off the turrets though, as they've taken most of the last 4 years to get to this point, and it'll be fun to return to the airframe side. I'm also working with Mark Evans to produce a replica "sit in" FN5 at 1:1, as a flat-pack kit using IKEA type construction, for museums, so am always busy.

If you're interested, I'll post some more images of aspects of the turret builds, and of course there are loads of films documenting the builds on you-tube simpkly search on "Fidd88".

"I'm no David Lean" I fear, so a lot of them are a little dull, with me pontificating on problems arising or sold. It's been quite a journey so far, learning to use CAD, making .stl files to make 3d prints, learning to tap holes in nylon, braze brass, fit tiny electrical connectors, use an airbrush, rivetting, make silicone moulds, casting, vac-forming, lathe-work... The list of new things learned is never-ending, which is what keeps it interesting, for me at least.

Attached are a few random pictures. The bullets in the feed-chutes were individually made, and linked together underneath so they could be twisted and curved within the chutes before being glued into position - which saved having to draw them in the correct curvature and then print them as a single file.

Attached Files mld2.jpgjig1.jpgrounds under false colour.jpgrounds over false colour.jpgX Section MK V Fixed ring bearings.jpgLMAsep3.jpgramcross2.jpglat-21.jpg.ce40c5dd0f6ccd48a3d19d292581e8fa.jpg
#4517199 - 04/19/20 02:32 PM Re: FN5 turrets for RC Wellington 1:4.5 [Re: Fidd]  
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That last photo gives me a scale reference for how big the whole aircraft will be! eek


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