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Westland Wasp HAS 1: 'Ambuscade Flight: XT778'


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On 8/8/2022 at 1:09 PM, TheBaron said:

Blessings upon you all.

 

Taking a break from writing up Vixen instructions so thought it was time indeed to make a few scratches on the wall here. Before proceeding though I need to publicly thank Mike (@bootneck) for his generosity in the sharing of technical references; it is  no exaggeration to say that without acccess to that level of information, I would not currently be contemplating this endeavour. Thanks also are due to Ian (@Wafu) in the matter of photographic sources : no doubt I shall be perstering your for brass rubbings of the Nimbus when the time comes Ian!

 

I've spent the past few weeks reading up from primary sources about several overlapping areas which are of direct concern to this build, to whit: how a helicopter capable of landing on a small surface out at sea which is rapidly translating and rotating in three dimensions was in fact developed, the main structural components of this vehicle and how they have to interact with one another in order to reliably accomplish this feat, and finally the integration of the Wasp into the MATCH (Medium Range Anti-Submarine Torpedo Carrying Helicopter) environment as a means of extending the ASW capability of a naval frigate via a radar umbilical. 

 

The above description is, if you like, the 'classic' profile which it was originally designed to fulfil but as is well known, the Wasp subsequently showed itself capable of a wide range of operational duties from the offensive (via AS11/AS12 missiles), to reconnaissance, casualty transfer and so forth. Equally well-known in the modelling circles are the overt visual differences between Scout and Wasp, which I don't intend to repeat here.

 

A quick survey of available literature might be useful place to start in terms of identifying the primary sources I'm relying on here, and why.

 

To augment reference photography, as a standard procedure now on builds I like to have original technical manuals to hand for cross-referencing so AP-101C-0601-3A, Wasp HAS 1 Illustrated Parts manual and AP-101C-0601-15, Wasp HAS Mk.1 Pilot's Notes are used here.

 

T. L. Ciastula: The Development of the P.531, The Aeronautical Journal / Volume 68 / Issue 642 / June 1964: in terms of the evolution of the Wasp out of the P.531 program, this remains a foundational, highly-detailed account. Ciastula was Chief Designer (Light Helicopters) at Westland-Fairey Aviation Division during this period so this is effectively an eyewitness document.

 

J. H. Stevens: Scout and Wasp - Westland's All-British Helicopters,  Flight International June 1964: drawing in part on Ciastula's account above, this article - as you would expect from a Flight one of the period -  contains what is still the best written description of the helicopter in terms of its structures, their construction and  functioning. The cutaway drawing is of great value in understanding the overall arrangement of features.

 

D. B. Bathurst: Maritime VSTOL — The Development of Small Ship Helicopter Operations in the Royal Navy, SAE Transactions Vol. 83, Section 3: 740525–740863 (1974): contains a highly detailed description of the Wasp/frigate  MATCH system in operation, along with a through discussion of approach, landing, ship motion, securing and deck handling problems. A lot of interesting information about Wasp-related matters not discussed elsewhere is included, such airflow and deck disturbance, as well as the Mctaggart-Scott system of which I was unaware:

52213012187_155d97aa95_c.jpg

Image credit: SAE Transactions

L. B. Bryson, F. E. Heenan, C. A. Johnson: Helicopters in the Royal Navy, The Aeronautical Journal / Volume 76 / Issue 740 / August 1972: Highly useful source in this instance on two counts: firstly it contains an excellently detailed history of helicopter development in the RN from 1915 onwards, secondly, the text provides the most detailed account I've found of the various (I think there were 19 in total) methods tested for securing a helicopter when landing on a moving vessel. Heavily illustrated throughout:

52271911540_783ab42234_b.jpg

Image credit: The Aeronautical Journal

Larry Jeram-Croft, Terry Martin: The Royal Navy Wasp: An Operational & Retirement History, Pen & Sword Aviation 2018: am currently reading this. First reactions are that this contains first class operational information not found elsewhere, but is let down by poor editing and design. Feels like a first draft. 

 

Adrian Balch: Westland Scout & Wasp, Warpaint Series No.110, Guideline Publications. 2017:   A valuable and comprehensive set of visual references, as you would expect. Can confirm on the basis of  photographic overlays in Photoshop that (allowing for the effects of focal length) Richard  J. Caruana's drawings of the Wasp published here look accurate in both shape and proportion.

 

If it is at all ppossible to condense the above into an introduction here without distorting matters through over-simplification, the Wasp then came into being as follows:

 

By the late 1950s it was becoming apparent that changes in submarine technology required ASW operations to be capable of being projected further out beyond the existing offensive range of small surface vessels such as frigates, in terms of both speed and distance. Leaving aside historical background regarding existing RN operation of the Hoverfly, Dragonfly, and Whirlwind helicopters (all of US origin)* in the maritime role, the Wasp  helicopter was developed out of a defined need for a light, turbine powered helicopter to fulfil such a role within the Royal Navy, in the form of the private venture P.531 project.

 

Subsequent to the two initial airframes which had a wheeled undercarriage, three further protoypes (known as the P.531-0) were constructed with  skid undercarriages in order for the Navy to examine the various problems involved in the operation and recovery of light helicopters from small vessels. Footage from this stage of the Wasp's evolution can be seen here:

It was during this period that many of the competing ideas (as referred to above in the Bryson/Heenan/Johnson article) for holding the helicopter in place on deck were considered, such as the suction pads seen here:

small_Saunders%20Roe%20Wasp%20P531-0%20X

Image credit: Navtechlife

Little known fact: the deck handling crew were required to wear those protective hoods because of the grotesque effects of suction which those discs had upon their appearance:

52270600202_113d724989_z.jpg

Undercarriage aside, in relation to the main design features of the Wasp it is worth noting how Ciastula states that in examining these, 'It should, however, be stressed that the very first P.531 could equally well have been chosen for this purpose, since all the main design features of importance were determined and incorporated in it.' (p.400).

 

As I believe in the primacy of pencil and paper when it comes  to working out three dimensional ideas, if you compare my rough initial sketch of the Wasp's  profile with the photograph of XN334 above, the continuities of shape become immediately apparent:

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As the design process develops over the coming weeks and months I'll bring in further information from the above sources at relevant points in the narrative. I still haven't decided which particular Wasp to build and must confess to being genuinely torn between wanting to build an AS12 wielding version so that I can include the APX-BEZU M260 sight, or one in its 'classic' Mk.44/46 torpedo carrying role. As it's my understanding that the latter version would not have had the sight fitted, I am sorely vexed as the sight is someting of an obsession, to the point that I bought some of the French manufacturer's specs via Delcampe:

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En Anglais for those who want to sing along with the band:

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There's a fascinating ten-part oral history interview over here  in the IWM archive that includes a detailed description (in pt.6) of firing a missile from the Wasp with this sight, as well as a genuinely engaging narrative of learning to fly naval helicopters in general in the earlier parts of the series.

 

Finally today, one matter giving me serious food for thought is that of the opportunities offered  by working this time in 1/24 scale. As well as the obvious disorienting effects of no longer being constrained by the size of part that I can consider creating - in terms of detailing - the other is that of creating a certain level of functionality in various regions of the airframe:

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  1. There's no reason why the tail rotor can't be a working foldable feature on robust hinges.
  2. It may be possible to experiment with having a castoring undercarriage as per the original (I also want to look into the feasibility of printing with flexible rubber resin for the tyres).
  3. I see no reason why it shouldn't be possible to have the blades being capable of being both folded back and opened. Whilst I've a lot more to look at and undertand yet with respect to the mechanical feaures of rotor gearbox and hub, it may be possible to do something fancy there also. We'll see.
  4. Cockpit doors should be capable of being openable/removable as per operational use.

But the sight....what about the sight....I want torpedoes but I want a sight too...it's not fair.

 

:bye:

Tony

 

 

*Regarding the preeminence of US technology in this regard, discussion notes at the end of Ciastula's paper to the Royal Aeronautical Society contain this superb reporting of the masculine 'Harrumph!' 

52270532022_ec97379a6d_c.jpg

 

 

 

If you are doing 3D printing why after all that design work dont you print 2, and have one with the sight and one with torpedoes?

 

Selwyn

 

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3 hours ago, TheBaron said:

Granted, with pleasure.

I say, Bang on, old boy. Patron, in Absentia, obviously. (I always think that a bit of Latin adds a touch of class to a thread.

 

3 hours ago, TheBaron said:

 more likely to have been a bald sheep temporarily airborne after a being hit by a Benny in a Land Rover.

I don't think you're  allowed to say the B word. The replacement term was a Still. Until Senior Officers banned that one too.

Service Humour. Hopefully it's still allowed. We worked hard and played hard back in the day. You were either a serviceman/woman or a Civvie. That simple.

All due respect to the residents who endured the war, many of whom (I've read) went out of their way to help the forces personnel.

I never got to go down there. I was working long hours & seven day weeks in a support role, back here in Blighty, at a certain Helicopter base.

Another book in my to read pile, 3 Days in June. 3 Para and Mount Longdon. Bless them all :poppy:

 

Very sad to hear that the pace of life is getting to you. (As it does to all of us at times. I arrived home from work today feeling ready for a nap!)

Maybe this one should be taken at walking pace, and damn the malcontents and their impatience. So, done by Christmas then? :poke:

How long is a Wasp main rotor blade in 1/24th? Will it still fit into your miracle machine?

Can you print a new brain? would it help? I could do with one myself on the odd day (or two).

Get well soon (Does the kettle lead stretch to the fridge?) Pete

 

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Sorry to hear of the ageing maladies dear heart. I too am an advocate of the nap. I have never however put the kettle in the fridge. (Yet) 

Now you’ve said the words it’s not likely than ever. 🥸

 

whenever anything happens it’ll be great so I’ll just be patient.  Exciting though. 🤗

 

Johnny

 

 

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4 hours ago, Brandy said:

If he does SHAR, presumably he'll have to do TRAY as well?

Call me dense Ian but I don't get this... 🤦‍♂️

3 hours ago, Selwyn said:

If you are doing 3D printing why after all that design work dont you print 2, and have one with the sight and one with torpedoes?

For the love of God Selwyn it took nearly three years doing two Vixens at 1/72... :facepalm: :laugh:

2 hours ago, Pete in Lincs said:

I don't think you're  allowed to say the B word. The replacement term was a Still. Until Senior Officers banned that one too.

I didn't realize that had military origins Pete.

 

Iinteresting bit of urban folklore to relate in that case as I picked the term up from a New Zealand guy I worked alongside temping for a job agency in London in, must have been about 1984-5 some time. He'd been a sheep farmer in NZ and was in transit to the Falklands, killing time in London whilst HMG shipped his family and all their possessions (inc. farm machinery!) halfway round the world to boost the Falklands population after the conflict. All expenses paid relocation to swell numbers.

 

He told me he was off to become a 'B', which I'd always just assumed was slang like Cockney or Scouser - having an unforgivable and deeply inappropriate sense of humour, reading up on the 'Still' bit made me laugh unforgivably and inappropriately I'm afraid.

2 hours ago, Pete in Lincs said:

How long is a Wasp main rotor blade in 1/24th?

I can tell you exactly as I've just been calculating the figures given in the Leading Particulars from the parts manual.

At 1/24 the diameter of the main rotors will be....

Blimey.

409.5mm!

 

35 minutes ago, The Spadgent said:

Sorry to hear of the ageing maladies dear heart.

Age me-bottom Johnny: Long Covid has me scundered and hangs around like an unwelcome wraith.

40 minutes ago, The Spadgent said:

I have never however put the kettle in the fridge.

And long may that continue! 😁

 

 

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Sorry to hear of your woes Tony. Brain fog is a curious condition that for me seems to increase, the more I learn things in life. I just call it overload!

 

Have sent a further PM with a few bits that might add a little cheer!

 

Take it easy.

 

Terry

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Happy to see an update on this, sorry about the LongC though, that’s something I hope passes soon, Tony.  Put a post it note on the fridge about the kettle, that’ll sort that issue I reckon.

 

 

Edited by mark.au
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9 hours ago, TheBaron said:

Too late sir. I am taking you steadfastly at your word! :rofl:

N.B. It's all Albert's fault guys

🤣😂

Edited by fatalbert
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Blimey Tony, I thought you were mucking around when you said about the kettle.

Sorry to hear about the Long Covid still affecting you, Mark's note suggestion sounds a good one.  Sending positive thoughts and hoping you can beat that thing ASAP.

Chris

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This should be a very entertaining thread!

 

Off to a good start, with the "suction cups" approach to holding a waspie on the deck... Knowing how much non-skid paint was applied to the deck of a Leander, the chances of suction-cups working would have been 0.

 

I shall pull up a barstool at the back of the room since all the front row seating appears to be full. Carry on!

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12 hours ago, TheBaron said:

Call me dense Ian but I don't get this

Sorry Tony, it was a reference to the notorious Sharon and Tracy characters. I think they started with Keith Waterhouse who was a journalist and had a column in the Daily Mail when it was still a reasonable rag. They were cashiers at a supermarket and he had some hilarious "conversations" between the two girls who were obviously not the brightest. Probably similar to CHAVS now but without the violent bit.

 

Ian

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I need to start today's post with an acknowledgement of particular kindness from @Terry1954 for shooting a hangar-load of images of (I think) XT437 in  Boscome Down's collection last weekend. Being shot with the eye of an experienced modeller, Terry's close-ups will help enormously later on when it comes to figuring out how the knee bone's connected to the thigh bone for areas like the articulation of the UC. Terry - my sincere thanks.

 

Having whinged about mental mists in the previous telegram, I've decided that the drawing process in Fusion can be turned to advantage as a form brain-training, so there is at last some material progress to relate.

 

Messages first though:

On 23/08/2022 at 21:32, Terry1954 said:

Brain fog is a curious condition that for me seems to increase, the more I learn things in life.

😁 I tried to think of something profound to add to that Terry but ironically...couldn't! :laugh:

On 23/08/2022 at 22:49, mark.au said:

sorry about the LongC though, that’s something I hope passes soon, Tony.

Cheers Mark: :thumbsup2: Having learned from the doctor last week that  there's a quietly growing epidemic of the Long-effects that's largely being ignored by media and politicians, this renders it comfortably invisible to the population at large with - at least  here in Ireland - only the families of those affected really conscious of the damage.

On 23/08/2022 at 22:49, mark.au said:

Put a post it note on the fridge about the kettle,

On 23/08/2022 at 23:47, bigbadbadge said:

Blimey Tony, I thought you were mucking around when you said about the kettle.

Sorry to hear about the Long Covid still affecting you, Mark's note suggestion sounds a good one.

*3 weeks later and kettle message is written across torso... 🤦‍♂️

91BcaUwCfVL._SX342_.jpg

On 23/08/2022 at 23:01, fatalbert said:

🤣😂

😁

On 24/08/2022 at 05:28, hairystick said:

This should be a very entertaining thread!

 

Off to a good start, with the "suction cups" approach to holding a waspie on the deck... Knowing how much non-skid paint was applied to the deck of a Leander, the chances of suction-cups working would have been 0.

Good to have you along Mr. Stick. 😄

 

That's interesting about the qualities of the landing surface on the Leanders:  the article in the Aeronuatical Journal by Bryson, Heenan, and Johnson - Helicopters in the Royal Navy - contains the most detailed operational account that I've been able to discover on the suction system. In relation to deck trials with the P.531 involving both HMS Undaunted and HMS Ashanti (running from 1961-2) they note both deck roughness and achieving a balanced suction seal as particular difficulties, concluding the section with the following wistful, if not wildly optimistic comment that: 'the system appeared to be one which could be made to work'....

 

Quite.

On 24/08/2022 at 06:55, Brandy said:

Sorry Tony, it was a reference to the notorious Sharon and Tracy characters. I think they started with Keith Waterhouse who was a journalist and had a column in the Daily Mail when it was still a reasonable rag. They were cashiers at a supermarket and he had some hilarious "conversations" between the two girls who were obviously not the brightest. Probably similar to CHAVS now but without the violent bit.

You are clearly cut from a finer cloth than myself Ian as my only point of rerence was San and Tray from Viz... :rofl:

21 hours ago, Pete in Lincs said:

They were later to be seen in Viz! under the title the two fat sl@gs. I'll leave the rest to your imagination...

I have just discovered there was a live-action film of them Pete: https://www.imdb.com/title/tt0382028/

Dolph Lundgren is in it.

I kid you not.

:boom:

 

The epic journey that only cinema can take you on aside, back to the naval aviation.

 

After the streamlined cadences of a jet aircraft, building a helicopter from scratch presents quite a different set of challenges for me. In some ways it will be more straightforward in not having to deal with matters like creating the intersecting compound curves of jet intakes and wing/nose, or having fuselage profiles hidden by tail booms. In others it will be immensely testing with regard to the complexity of the exposed engine and increased level of deail required all ove at 1/24.

 

To assist with getting the general profiles of the airframe correct in shape and proportion at the outset, the first step requires building a reference mosaic in Pureref:

52308965757_e909ffc638_z.jpg

This general arrangement panel shows a series or representative views of the Wasp, organized into side, front, 3/4 aspects etc. so that you can readily cross-check features from mutliple angles in one place. Discovering recently that this software also enables you to collate images straight from the web without needing to download them first was a massive help this time around in organizational terms. Later on I'll produce similar panels when it comes time to get stuck into filling in the various regions down to the finer levels of detail; for now though this is enough to be going on with.

 

Prior to commiting any of the above to splines though, it was necessary to devote some time to reducing the dimensions of the leading particulars to 1/24th scale. It was a bit of a shock to discover that with rotors extended, the finished model will be over 50cm in length!

 

Anyway; armed with a set of figures regarding the length and width of various key datum points around the place, these were diagrammed out in Fusion as a three dimensional graphical 'cage' that will serve to define the exents of the airframe and rotors:

52305486237_31e64e8da3_b.jpg

As you can see, in this form it's basically a Wasp as a stick-figure drawing.

 

With the Vixen being the first time of designing a whole aircraft from scratch, I made multiple mistakes out of naïveté/inexperience back then which had a tendency to make matters more complicated later on than they needed to be (despite the ability to step around the ttimeline parametrically).

 

One of the key 'noob' errors I made was in putting too many drawn sections into single sketches (even when using the same plane). This time around I've been much more circumspect in having critical outlines of the aircaft contained in separate sketches.This creates a series of layers that you can turn on and off at will in order scale the amount of detail visible at any one time.

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The other key error I made was to work in solids rather than surfaces, but more on that in due course.

 

Each of these extents is dimensioned, meaning I can't accidentally disturb any of these key criteria later. In this form you can probably sense what's going on regarding the rotors and undercarriage, but it's not until you add extra planes and begin the process of spatially organizing the drawing process that the familiar outlines of the Wasp slowly begin to emerge:

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I say 'spatialize' because of course in this form these are all still 2D drawings, albeit ones on separate planes in three dimensions:

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As I mentioned above, by building up the overall airframe as a basic cage first, it's a more prolonged but holistic process allowing further adjustment and revision at much more aadvanced stages when a specific error may become suddenly apparent.

 

The other obvious factor I've fogotten to mention is that I'm only building the stbd side of the helicopter to start with, due to the symmetry of the basic airframe and undercarriage. It's common sense to build once, then mirror. Only later with engine and surface details does asymmetry become an issue.

 

Wasp-ish, if not Wasp-like....

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In transferring a load of family photos onto the cloud from HD recently I came across some shots tmy youngest took at Yeovilton well over a decade ago, including this one of XT778:

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Turns out the lad was mad for a bit of naval aviating:

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(He now towers over me like a giant.)

I never realized that he'd taken also some interior shots of his own (he was only 6 at the time):

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If you look out the windscreen you can see his old man with arms crossed: I appear to have spotted a van selling pies.

 

Thanks for looking in as always and glad to be posting actual results this time.

More as it develops,

:bye:

Tony

 

 

 

 

 

 

 

 

 

 

 

 

 

Edited by TheBaron
Revised for inadvertantly obscene misspelling of 'account'.
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Thanks for sharing your design process. I can see I need to up my skills in using surfaces, especially how to loft. With the Battle now finished, the little Model T ambulance is going ahead at a rate but I still haven't figured out how to go about the folded canvass "bag" at the rear end. I think lofting is the answer, but I need to figure out how!

 

Ian

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Amazing, although a bit double dutch to me due to me being thick!!!  I am looking forward to bits being stuck together Tony 😉 great start. Got a 72nd scale wasp kit on order myself so looking forward to your thread for inspiration. 

Chris

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5 hours ago, TheBaron said:

I have just discovered there was a live-action film of them Pete

I'll watch that at the weekend. I need to be able to get to sleep tonight, pure in mind & body. Ready for an early start at work tomorrow. Thanks.

I think I may have actually understood some of your planning and plotting. I love it when a plan starts to come together.

That shot of the instrument panel is a belter. Your giant was obviously a young David Bailey. Did you get to the pie van?

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On 23/08/2022 at 21:11, TheBaron said:
On 23/08/2022 at 20:23, The Spadgent said:

 

Age me-bottom Johnny: Long Covid has me scundered and hangs around like an unwelcome wraith.

Oh no. I didn’t realise. 🙁 That long Covid can do one. Hope you settle soon my good man. 
 

J

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Apologies in advance for all the  crumbs spilled over this post, your humble correspondent is currently cramming fistfulls of rapsberry cake down his scrottle on account of a sudden glut from the garden that the blackbirds and thrushes have temporarily overlooked.

On 25/08/2022 at 14:08, Brandy said:

Thanks for sharing your design process. I can see I need to up my skills in using surfaces, especially how to loft.

It's strange being back in Fusion and getting a feel back for the necessary processes Ian! If there's a difference this time around it's that I've learned a bit better how to draw things with a greater economy of means, relying a lot more on the use of control point - as opposed to fit point - splines, allied to greater use of constraints and dimensions in order to lock accuracy in, in a more sympathetic form when it comes to the inevitable design revisions later on down the timeline.

On 25/08/2022 at 14:08, Brandy said:

the little Model T ambulance is going ahead at a rate but I still haven't figured out how to go about the folded canvass "bag" at the rear end. I think lofting is the answer, but I need to figure out how!

I adore that little ambulance! 

 

Don't know if it helps but for the various seat cushions on the Vixen (which needed to be more organic and irregular in shape and volume), I used the 'create form' tool in the Solid design space. That purple cube-like icon triggers it's own separate workspace (seen below) that lets you sculpt from a solid mesh rather than draw from scrach:

52315112179_e128df5cf4_b.jpg

Just like working with any polygonal mesh in a 3D program, those individual points and lines as well as faces can be moved/rotated/scaled around independently to sculpt the required shape, just increase the face count to give the required amount of surface sub-division for the number of folds and indentations you need for the job.

HTH.

On 25/08/2022 at 16:38, bigbadbadge said:

I am looking forward to bits being stuck together Tony

 How far forward in time are you looking Chris? :rofl2:

On 25/08/2022 at 16:38, bigbadbadge said:

Got a 72nd scale wasp kit on order myself so looking forward to your thread for inspiration. 

Oooh, cracking stuff! :thumbsup2:

 

On 25/08/2022 at 19:21, Pete in Lincs said:

I need to be able to get to sleep tonight, pure in mind & body.

Saint Peter! 🤣

(How I envisage you out delivering beer)

490px-St._Peter_Preaching_in_Jerusalem_L

On 25/08/2022 at 19:21, Pete in Lincs said:

Your giant was obviously a young David Bailey.

He's grown up surrounded by moving image and stills cameras of various descriptions Pete, and seemingly absorbs their use by osmosis.

On 25/08/2022 at 19:21, Pete in Lincs said:

Did you get to the pie van?

There are no painful memories to suggest otherwise. :winkgrin:

On 25/08/2022 at 23:39, The Spadgent said:

That long Covid can do one. Hope you settle soon my good man. 

Thanks Johnny. 🤝

 

Having some essential dimensions to plug into proceedings is important of course but at some point it's always a good question to think about where to start building from when it actually comes time to start throwing shapes up on the screen. In the case of the Wasp I decided to begin at frame 11 (the red line in the image below):

52314773911_5b3617a3a1_b.jpg

Being the rear bulkhead of the cockpit cabin, this frame serves (at least in design terms) to separate the crew acccomodation at the front from the engine and fuel areas behind. It makes sense I think to pick this point for several reasons but primarily because it enables me to build outward in both directions along the major axis of the helicopter from a structure of known dimension. This should (I hope!🤞) preserve me from errors in shape and proportion as the aircraft grows over time.

 

Working backward from frame 11 (red) to frame 80 (blue), frame 16 (green) represents a transition region from the gentler curvatures of the cabin structures to the cicrcular cross-section of the tail boom. The predominant internal features of this region are the three intelrlinked fuel tanks (clustered around the centre of gravity of the aircraft) with, in the centre below the main rotor grearbox, the various servos and control linkages for translating cyclic and collective inputs to the rotors, alongside other fittings like the autopilot servo motor. 

 

Starting by blocking out this region in its most basic form, I adjusted the the various outlines so that they looked as simiilar as possible to the same areas when seen from multiple angles in photography:

52314557918_73e2468924_b.jpg

It's not of course until the drawings become surfaces though that you can really begin to address the accuracy (or not!) of your observations:

52314247256_ca79ae80e0_b.jpg

It's one of those subtleties of the airframe that the outer edge of the engine deck doesnt simply angle back as a straight line from Fr.16 but displays a more abrupt curvature inwards at the rear as it approaches Fr.80. Congratulating myself on catching that detail didn't explain my nagging sensation that something still wasn't/nae right with that engine deck however. It seemed a good time to go back and skim the original 1964 Flight article (God how I miss that archive) which -as proves often the case - contains some of the finest descriptive writing of specific aircraft to a degree rarely surpassed by any subsequent publications:

52315278254_5a85d91ebe_z.jpg

Of ourse! :doh: The trough!

Being masked by the engine, that feature isn't readily apparent in most photographs but no excuse whatsoever for me not catching what was clearly visible in drawings in the manual.

 

That outer raised section of the deck surface still looked too wide though and didn't match the width of the rear window section of the cockpit that protrudes backwards into that region. If I pulled the inboard line of it outwards any further (to align withthe windows) it would cut in to the tapering outboard line of the deck surface before reaching Fr.80.

 

What was going on? All of the surrounding datum points appeared to be matching up with the features of the aircraft they were representing so something was certainly ahoo, but what?

 

In the end I looked very closely at one particular drawing in the manual - which displayed the deck surface free of other fittings -  and noticed that the inboard line of the deck trough isn't in fact straight, but is further outboard than I had it at Fr.11, with a slight but noticeable dog-leg at Fr.16, enabling it to angle inwards to maintain the correct alignment where it meets Fr.80. Some judicious use of the ruler on other drawings subsequently confimed this observation. From some angles such a  feature of the trough/deck outline is subtle enough that you can't actually see the deviation.

 

Corrected version:

52314675529_90e45d41b8_b.jpg

Later, with added boom (Fr. 80 to tail cone fold) and rear face of cabin window panel:

52314688370_bf5c15a298_b.jpg

You can't represent it in static images but I'd noticed previously on the Vixen that you can catch flaws in your work by rotating parts in the (virtual) light and watching how the highlights travel over them. As it works best with darker colours I slapped on an approximation of blue-grey for a test-twiddle:

52313448752_b78d46cca7_b.jpg

Sure enough, I didn't like what I was seeing when rolling around the undersides - that section from Fr.16 to 80 remains 'boxy' for too long as it travels backwards.

 

Cultprit?

 

Again, back to the frame drawings in the manual to notice that about 2/3 of the way back in that region the frames suddenly become cicrcular in order to manage the transition between the two types of shape:

52313853087_0852fa2089_b.jpg

Much better with that extra circular frame added now:

52315092085_d42f58d961_b.jpg

Under blue-grey that's more convincing:

52314960298_b110128fa9_b.jpg

Next step will be to follow a similar method of creating the folding tail cone section up at the back:

52315076159_bbff4ff388_b.jpg

From that point on the fun will then really start when we get into all the bulbosities and bulges of the cabin and cockpit section as we head towards the nose.

 

I nearly forgot to mention that one really useful set of photographic references to have in this latter case are those mournful shots of old Wasp frames, such as this corker. Terry also had a couple of nice close-ups in his recent Wasp photoshoot that are equally helpful in the matter of identifying shape and structure in skeletal form, almost like being able to follow a diagram from the manuals....

 

That's it for tonight friends. Take care of yourselves until next time.

:bye:

Tony

 

 

 

 

 

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20 minutes ago, TheBaron said:

(How I envisage you out delivering beer)

I was nothing like that on Friday. The Newark bypass was shut down after a bad accident. The town was gridlocked as everything tried to get through.

Guess who had deliveries there in that heat. I ended up running well over two hours late. Stressed & sweaty! So it turned into an almost 11 hour day! 

Home, power shower, beer and pizza made it all better though.

You're catching some nice details as the design comes to life. I knew about the trough from a previous build on here. A leaky engine? how unusual. 

That Wasp wreck is a sad sight, as are all similar wrecks when you consider how much care had been taken of them during their service lives.

Hope you're feeling better as the days go by. Take care, Pete

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Impressive start in Fusion there Tony.

 

So now the questions begin ........... How will you determine which sub assemblies will be completed separately for final assembly "in the real world". I'm guessing actual print plate size is a factor? So perhaps in the above we are seeing at least two major sub assemblies? Even a Wasp in 1/24 is going to be pretty large!

 

Terry

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13 hours ago, TheBaron said:

How far forward in time are you looking Chris? :rofl2:

Well not too far by the way you've started😉 You've done well and if you continue like this, you will be building in no time!!!

Seriously though Tony  great observations and drawing/plotting,  looking forward to the Airframe development. 

Chris

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Bittersweet  here as the final days of summer shade into autumn beneath the cloud lanes:

52324425206_9a910e6a2c_h.jpg

 

On 27/08/2022 at 21:30, Pete in Lincs said:

Guess who had deliveries there in that heat. I ended up running well over two hours late. Stressed & sweaty! So it turned into an almost 11 hour day! 

Home, power shower, beer and pizza made it all better though.

 

No point saying 'take it easy' when events conspire otherwise Pete but wishing you relaxation when the chances come.

On 27/08/2022 at 21:30, Pete in Lincs said:

You're catching some nice details as the design comes to life.

It certainly is a good discipline to realize that what you thought were the things that give the Wasp its particular visual character, turn out in actuality to be terribly simplistic in nature. Nothing like having to arrange lines in space to bring you up short! :laugh:

On 27/08/2022 at 21:30, Pete in Lincs said:

That Wasp wreck is a sad sight, as are all similar wrecks when you consider how much care had been taken of them during their service lives.

They should be turned into ship burials like Sutton Hoo so that future archaeologists can reconstruct the history of The FAA People who once migrated across oceans.

On 27/08/2022 at 21:57, Terry1954 said:

How will you determine which sub assemblies will be completed separately for final assembly "in the real world". I'm guessing actual print plate size is a factor?

Bang-on in that Terry. Build volume from the combination of plate size and z-axis height is the prime factor The length of the airfame from nose to tip of the tail cone will be about 36-7cm alone, which is one of the (several) reasons I'm keeping everything as surfaces so far, to let me take decisions once the whole airframe is blocked out about how it might need dividing. Other no less important factors are which printing orientation is optimum and what parts of the aircraft you want resting on the printing supports.

On 27/08/2022 at 22:53, hendie said:

Nice start Tony. 

Thanks Alan. :thumbsup2: I'm slowly find the Fusion skillset returning and finding it valuable brain-training whist the fugues are still hanging around.

On 28/08/2022 at 08:51, giemme said:

So the magic has started!

:rofl:

I am a mere dabbler compared to proper magicians Giorgio. Ricky Jay just blows my head:

 

On 28/08/2022 at 10:42, bigbadbadge said:

You've done well and if you continue like this, you will be building in no time!!!

:laugh: aside Chris: this thread has gotten onto the designing stage a lot quicker than the Vixen one did!

 

Picking up the reins from where we left off the engine deck/boom last time, I added the tailcone to the rear section:

52317584553_a7322bd8e8_b.jpg

Unlike the boom itself, the cross section of this is circular but with a truncated top surface, required to accomodate the angled tail rotor gearbox and associated driveshaft coupling. Inevitably that will be hidden by the driveshaft fairing of course:

52317268131_2b501fcc27_b.jpg

One important point to note about the front of that tailcone fairing is its asymmetry - the side profiles of it differ slightly in shape and extent, in order to allow  (I'm presuming) the tail cone to fold back round when it's locked into the extended position for flight:

52317584558_f50713e17d_b.jpg

I'll leave it in this raw state for for now though and trim to the correct profile(s) when it comes time later on to mirror the stbd side and create the port half.

 

Having blocked out the shapes for the rear, it was time to move in the opposite direction and begin doing the same for the cabin and nose areas:

52317712060_599b00c840_b.jpg

For this region I'm basically following the box-girder chassis of the actual helicopter, using the bulkhead shapes as lofting profiles:

52317584638_80e30068b7_b.jpg

As you get closer to the nose you begn to move away from the simpler structural frameworks at the rear of the helicopter and into the more complex compound curves of the forward cockpit and nose. In actual fact i got a bit ahead of myself at this stage because although the curves of that front 'chin' we working nicely, once I began to introduce some profiles for the nose itself I began to run into contradictions in shape between front and side views:

52324726308_7a9ac8ca59_b.jpg

I couldn't work out for some time where I was going wrong until eventually noticing that the leading edges of the front doors actually sit in front  of the windscreen line:

52323743117_509d1c7bc0_c.jpg

As I'd been using that windshield line as a datum point for the rear cross section of the nose, this had thrown my front/side alignments into disarray! There's a lovely shot showing the interior view of this region over in the walkaround section of the forum:

w%2039.jpg

Image credit: 'Graham' (not sure which one!)

Duer to this overlap, it made more sense to backtrack and fill in the door/cabin panels first, before proceeding forward of those on to the nose:

52324846285_51a8d55039_b.jpg

I had a lot of issues getting the changing curvatures at the front of the pilot's door adequately expressed, in terms of the manner in which said curvature of the panels become more acute toward the front of the vehicle. It gives a kind of subtle downward angled 'jawline' to the shape of the helicopter in photographs that region, which is actually easiest to discern in such images by the way it warps reflections and highlights of the surrounding environs.

52324406436_68055ab1d6_b.jpg

Periodically I like to mirror the work in progress in order  to check it for accuracy as (at least for me) it's frequently hard to work out from just one side of an aircraft if the shapes are right:

52324406431_a07d1c8feb_b.jpg

Also, turning it around in the light every now and again lets you catch any errors and distortions as highlights travel around the forms:

52324846330_a2c3f8cf70_b.jpg

I think I'll hold off on the nose and concentrate next on forming the rear of the cabin, followed by all those 'interesting' flowing curves of the roof structures. That should give me a clear windshield line to then start organizing said schnozz in relation to both it and the side doors.

 

A final - pleasing - note to end on toda: the etch for the Vixen kits was delivered yesterday and I just don't remember the last time I was that  nervous opening a packet!

52324860260_d3697f7a58_b.jpg

I had this done by PPD over in Scotland; absolutely top quality work from the team there - the crispness they've acheieved with this is pure class.

 

That's me for today: off now to deal with the tomato glut by making a sauce for some tortiglioni.... 🍽️

:bye:

 

 

 

 

 

 

 

 

 

 

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1 hour ago, TheBaron said:

That's me for today: off now to deal with the tomato glut by making a sauce for some tortiglioni.... 🍽️

:bye:

Beware Tony, Italian Kitchen Patrol is around and watching you.... :bobby:  :rofl:

Great to see the chopper shaping up - even greater to see the Vixen's PE parts :tasty:

 

Ciao 

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It may be part witchcraft but things are looking rather good already. There does seem to be something amiss at the tailboom joint in this one?

 

52324406436_68055ab1d6_b.jpg

A bit of a ripple? No doubt you've caught it though.

Brain training? where do I sign up?

That etch looks the biz!

 

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