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Westland Wasp HAS 1: 'Ambuscade Flight: XT778'


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19 hours ago, TheBaron said:

Only at this point did the sheer size that of the model start to hit me! Is it possible to be afraid of your own work? :laugh:

 

 

Ask Dr Frankenstein, he might be able to answer your question.

 

Gondor

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Fabulously impressive post mortem as always. But I have to ask, is this a model of the terraforming plant from Aliens?

It all looks very smart. I like the 'Alas poor Yorick' I glue him well. As you say, it's a fair size. If you leave it in view on the desk you may get used to it.

The gearbox and engine details came out very well. As did that nice smooth boom. The flushing idea was a real light bulb moment!

Keep them coming!

 

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On 1/12/2023 at 8:49 AM, TheBaron said:

Good evening everyone. I have some prints to show you this evening but in time honoured fashion will delay matters pedantically by replying to posts first...

As events proved, this was somewhat optimistic on my part Pete and was the one bit that didn't work out as planned! 

Or as I believe Spike himself once averred:

'We haven't got a plan so nothing can go wrong!' :laugh:

:rofl2:Take your tablets Anthony - I have some news for you in a moment... 

Remaining as I was sah.

Whatever that might have been..I forget now.... 

This seems an historical constant regarding how power treats service.

 

Thnx for those torpedo envelopes Crisp - good solid operational material of the kind this thread feeds upon.

 

So the Saturn has been quietly doing its thing in the cupboard over the last few evenings and I now have three sets of test prints to examine:

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Despite the absolutely filthy FEP in the print vat (which badly needs replacing) the printer just kept churning out quality parts as if it wasn't being asked to print through a semi-opaque window. The only failed resion amongst the whole bunch was the rear underside of the cabin area; if you remember in my previous I talked about the dangers of suction in this area and I think in the end the sheer volume of the piece proved too much for the supports, as they shifted during the print to give wavy where straight should be:

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It's a simple enough problem to solve and really results from me being such a noob at printing 1/24 when it comes to the increase in part strength required. Next time out I'll both thicken the floor/underside areas and print them as a separate section to avoid the cabin area being too big a single part. The rest of the part turned out nice and smooth though, with very little going to be required in the way of sanding:

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As I had a bit of time to kill until the second set of prints was ready I kept myself amused by gluing the two halves together for an 'Alas, poor Yorick!' photo opportunity:

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Only at this point did the sheer size that of the model start to hit me! Is it possible to be afraid of your own work? :laugh:

 

In all the following shots you're seeing the parts fresh out of the resin, which is to say, they've been washed but not cured in UV yet or tidied up in any way. This won't be a full parts inventory, just an initial look over of representative parts freshly hatched and still on their support structures.

 

The rear wall of the cabin also gave me pause upon realizing the width of the beast:

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Similarly feelings too at handling the main rotors:

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Printing these required some creative thinking in the custom support dept. due to their obvious length/width relationship. To solve this I designed  vee-shaped verticals support in Fusion that would run the length of the leading edge but which only had a contact point 0.14mm wide to assist with removing the blades from them later. In uncured condition they come with built-in rotor droop:

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Once cut free it will be interesting to see if I can get the droop and twist starting in the right place pre-curing...

For the pipes of the oil system I used the same 'vee' method of vertical support, combined with print supports added in Lychee:

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Despite the thinness of the parts in question, this seemed to work quite well, though at 0.45mm ⌀, the oil scavange pipes in the middle of the three there may well need replacing by wire at the building stage due to their fragility. By contrast though, I think that the MRGB support pylons will work out Ok as resin, just so long as the brass main driveshaft bears the bulk of the weight:

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The quality of detailing on the MRGB exceeded my expectations as a printed item:

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Ditto with the front and rear of the reduction gearbox, which were equally sharply delineated down to the last bolt:

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The new version Of Lychee has introduced a slightly different way of thinking about the use of anti-aliasing in printing and I must say on the strength of these ribbed sleeves for the spider arms, it handles small concentrated areas of detail with verve:

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By contrast, larger sections like the boom have a pleasing smoothness about them, and don't look like they requiring much work later in the matter of clean-up:

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Probably just as well with the number of rivets it's going to need draped along its length....

 

One issue I encountered repeatdly on the Vixen and again here on the Wasp as the need to remove any excess liquid resin from the inside of hollow parts. Previously I'd done this by pumping compressed air down one hole in order to force any residual resin out of the other drain opening but recently hit upon the idea of making drain holes large enough that you can use a needle and syringe to pump IPA directly into the patient to sluice them out and yes this is suddenly starting to read like a post-mortem report....

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Anthony - this next bit is for you in thanks for all the Wasp measuring. I not only test printed the MGB at /132 but had a crack at the Nimbus also, in order to give you a sense of how much detail remains after the Alice in Wonderland treatment down a scale:

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Uncured resin like this always looks a little waxy but I'll get  some UV on them in the next couple of days:

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Aside from the preservation of detail down at 1/32, the other issue that impressed me here was that I was able to get away with printing the engine like that with just a few supports along the underside and yet the compressor ribs etc. all stayed in place. The 1/24th version I split into three and printed vertically but wondering if I need to do that now. I'll take a better look at it tomorrow with the supports off to compare the difference.

 

Anyway, this is everything I've printed up until now:

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Over the next few days those parts'll get removed from their supports and cured in the UV station, then we can have some fun whacking a few of them together to see what it looks like as a test assembly!

 

Bon nuit mes braves.

:bye:

Tony

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Holy Bajolee.......:hypnotised:

 

Lost for words is an understatement!....ummm, I'll have a go.  You really have captured the essence of the Wasp already in what I can see.  For a test print, you must be mighty happy.  What I can say is that you sir are a true artist in every sense.  I have followed your builds for a while, but this next level engineering.  All your hard work has not been lost on me following along although my brain hurt watching and understanding what you were doing.  3D CAD is next on my list to learn, you and Kerry have inspired me:wub:

 

That's absolutely magical!!!!!  That is a sight I never thought I would ever see.  You sir are my favorite person in the world!  Well after my wife of course LOL

 

I will go find me some pills now:D

 

Cheers

Anthony (with the Huge smile!)

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 Bit more in the way of physical evidence to share with you this evening, this time in the somewhat important matter of assembling parts and whether they will.. Speaking of assembly though, time to take the register first before leading off on the forum hymn 'For Those In Peril On The Tea':

On 11/01/2023 at 21:41, Galligraphics said:

wow.... 

Ta Nige. :thumbsup2:

On 11/01/2023 at 21:44, CJP said:

More Wasp magic! - your spells seem to be working well

Thanks CJ. :thumbsup2: Purely by coincidence I very often have that old 90s series Charmed burbling away on Prime in the background whilst I'm working these days - the Wasp must be absorbing Wiccan energies! :laugh:

On 11/01/2023 at 23:42, k5054nz said:

Magnificent!

Kind of you Zac - my thanks!

On 12/01/2023 at 06:59, Ex-FAAWAFU said:

Blimey!

Don't suppose you've got a spare McTaggart Scott deck winch to help me manouevere this monster around the bench Crisp?

On 12/01/2023 at 07:18, perdu said:

Jehosephat!

 

Let him jump!

😁 You made me go and look up Jehosophat and jumping Bill and I promptly fell down a rabbit hole of something called 'minced oaths' that I never knew about before....

On 12/01/2023 at 08:26, Terry1954 said:

Wot they all said with knobs on!

Dangerously close to mincing an oath there Terry! 😁

On 12/01/2023 at 09:09, brianthemodeller said:

By ‘eck petal!

😁 You're a very kind man Brian.

On 12/01/2023 at 09:25, kev67 said:

Very impressive results

Cheers Kev: I must say the printer is behaving itself in this cold weather, even if I do have to heat the resin up on the stove, like something out of a 19th century railyard....

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On 12/01/2023 at 12:06, hendie said:

The Saturn looks like it's doing a great job with those prints.  Now If only I could find a justification for a larger print bed...

I see a 1/24th scale triplane in your future Alan.... :devil:

On 12/01/2023 at 14:09, heloman1 said:

Those parts look magnificent Tony, the long hours with the drawings/renders has paid dividends handsomely.

Gracious of you Colin - thank-you!

On 12/01/2023 at 15:30, giemme said:

Utterly impressive test prints!

Damn decent of you to say so Giorgio. I must say that the printer itself has to take a lot of the credit here - I've got more confidence in the consitency of output quality using the Saturn 2 than I had with any of my previous printers, particularly on thinner and more convoluted parts.

23 hours ago, Pete in Lincs said:

I have to ask, is this a model of the terraforming plant from Aliens?

:rofl2: It's a shake-n-bake Wasp....

23 hours ago, Pete in Lincs said:

If you leave it in view on the desk you may get used to it.

I'm less scared of it today Pete now that I've seen that some of the bits do fit together as intended! :rolleyes:

20 hours ago, keefr22 said:

Hmm. Well, yes, ummm............

Strong Hugh Grant vibes here Keith. :winkgrin:

9 hours ago, Anthony in NZ said:

For a test print, you must be mighty happy. 

Oh I am Anthony. Sometimes this CAD/3d printing lark feels like the equivalent of a horribly complex accumulator bet paying out: whilst you think that you've rationally anticipated the relevant factors based upon previous experience, the minute you push the 'print' button on the screen  some deeply atavistic part of yourself wordlessly beseeches the aid of higher powers....

9 hours ago, Anthony in NZ said:

You sir are my favorite person in the world!  Well after my wife of course LOL.

My compliments to this fine woman upon choosing such a discerning husband....:rofl:

 

The bulk of the larger prints have all been de-supported and cured now although - lest people think that finishing standards have slipped deplorably round here - I'm not doing any filling or sanding here on a test-bed whose sole purpose is to identify stuctural and assembly problems in advance of the actual build. This quite naturally gives me the opportunity to produce a snag list of asny feaures that need revising back in Fusion.

 

The main focus today then was on looking at all the potential weak points associated with fitting the Nimbus to the engine deck.

 

The combination of ECU, mounting components and reduction gearbox all have to fit in and around each other 'on deck'  in a manner both visually faithful to the original, and strong enough to take the strain of all the components involved. 

The main 'core' of the engine (oil tank, compressors, turbines, exhaust) is built up from four main parts:

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The only real issue in putting these together (using my standard gluing SOP these days of laser and resin) was that I need to add a second locating peg to both the compressor and turbine sections of the main tunnel to help line them up more easily along the central axis:

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Particularly pleasing at this early stage was the fit of the exhuast forks into rear end of the turbine; I'd allowed about 0.1mm for shrinkage at this scale and this as it turns is just right for a nice snug union at this scale.

 

The reduction gearbox and it's associated fitttings printed very nicely as integrated units and went toghether without too much fuss:

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Outwardly those look fine joined together but an item for the snag list is the vertical seam where front and rear halves meet - more supports needed in Lychee to resist vertical drag in the resin as they're a little 'bowed' to be acceptable.

 

Moving forwards along the Numbus to where the engine sits on the front ECU pillars, my plan of using diagonal brass inserts to pin these components together in a way that transmits the weight of the engine downward (without fear of breaking the joint) worked out as intended:

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Those rods actually go up all the way inside to meet at the apex of a traingle inside the top of the engine, sturdy but invisible:

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From here it was rearward again to the 'cradle' which is bolted the front of the reduction GB, and which provides the main means of attaching this unit to the rear of the Nimbus:

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I call that semi circular ribbbed fitting a cradle simply in absence of knowing its real name. It's quite a delicate part even at this prodigious scale and although it fitted onto the GB using the mounting points provided quite nicely, I was more concerned really about then fitting all of that onto the Nimbus in terms of: a) would it all actually align as intended, given that it has to simultanously slot around a collar on the engine whilst at the same time its top works fitting in between the exhausts forks, and b) would I break anything off in the attempt?

 

Anticipating a lot of trouble I was rather taken aback that it went on first time, as intended:

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No trumpet blowing intended here, I genuinely did not presume it would work so smoothly. The join is nice and strong as well.

 

That shot above also displays (at the 10 o'clock position as we're looking at the GB)  the rear mounting point for the ECU. Similar to the front set but in more robust fashion, my plan here  also used brass but in this case 1.0mm⌀ tubing which penetrates all the way through both deck mounting points the GB itself, giving sturdy support for the rear of the engine. This also gave a pleasant excuse to get out the brass cutting rig:

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I like working with brass so much that I'll occasionally wander into the studio and cut a piece just to assuage the addiction. You mustn't tell anyone that though.

 

A section of the required length, inserted:

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Being from the 'glass half empty and then I knocked it over' school of pessimism, I still harboured lingeringdoubts that all those section comprising the Nimbus and GB would finally line up neatly along the engine deck.

 

Well, they did - and in all honesty colour me most surprised of all at the final ease of fit:

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Aside from having to clear a little resin residue out of the front set of holes in the deck, there were no problems to report in dropping that assembly into place:

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Aside from the visuals, the physicalstrength of those two sets of supports - especially the rear set - is critical on this build. This is due to the fact that later on I'm going to have some 2mm metal tubing for the main driveshaft running from reduction gearbox to MRGB. This is so that the combined weight of the MRGB and main rotor system isin fact taken in the model up by a metal component rather than by the resin pylons of the MRGB itself, those latter components primarily fucntioning here to provide stability and aligment. Speaking of which:

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Again, allowing 0.1mm shrinkage in the print designs meant the transmission spins quite-nicely-thank-you inside the MRGB.

 

That was enough for one day but I woudn't have slept easy tonight without knowing that these designs were feasible as a working concept. It's not that I'm going to be running round the house with the finished model making turbine noises - much - but I do want a small number of working features to function without undue risk of the model falling to bits.

 

As Sol promptly emerged from the stratus undulatus at the end of that session, I shimmied outside for a few summaries in natural light:

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A modest number of items on the snag list to attend to in good time, but nothing major needed so far in the way of design revisions:

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The main rotors next time. I actually hung the blades up somewhere dark and cool so that they wouldn't cure before I was ready and can you believe a person could lose something that big? Well yes..as it happens... :facepalm:

 

Benisons upon your modelling.

:bye:

Tony

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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Prints look very good and take a handful of smarties for getting assembly so spot on first time around.  

 

Talking of droop... you keep mentioning droop in relation to the rotor blades.  I was under the impression there was no droop in the Wasp/Scout rotor blades as they were so short (relatively speaking).  I seem to remember an elongated discussion on this matter some time ago in a forum not far from here.  Now I could be (and most probably am) wrong, but seem to remember the outcome of the discussion was that there was no sag in the blades themselves, but parked and at rest the blades did angle downwards significantly.

Someone posted a very good photograph to illustrate this fact.

 

I have no idea about the twist though being 17 in '77 I can tell you all about the pogo should you wish to inquire.

 

 

 

 

 

 

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2 hours ago, Pete in Lincs said:

It's Friday so I've had Pizza

Snap! 😁

2 hours ago, bigbadbadge said:

Crikey what a catch up, how exciting to see the test prints which look wonderful,  going together and what must be a pleasingly short snag list too Tony.

Thanks Chris: I'm sure I can add to that list in due course. 😄

2 hours ago, giemme said:

Exciting to see some of the main pieces being assembled - even if it's just a trial fit!

Thanks Giorgio. There is something genuinely satisfying about the process - even discovering which bits didn't quite work!

1 hour ago, hendie said:

.  I was under the impression there was no droop in the Wasp/Scout rotor blades as they were so short (relatively speaking).  I

You're exactly right to chide my error Alan - in fact I even had Crisp's confirmatory post in that thread in question bookmarked to remind me of just that fact, for all the good it did me.

 

A more accurate statement of affairs is that the blade twist from certain angles made me see an illusory droop. There are some fine examples of this phenomena in the Wasp photo group on Flickr (apologies for lack of link but I don't know how to pull a url from a group page on the Flickr app...).

 

Many thanks for your timely intervention, which prevents me doing something unfortunate when curing the blades to tomorrow!

 

This pogo you mention - it wasn't a ground resonance effect caused by Steve Severin? :rofl:

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Tony, seeing some of the hard copy come together, albeit in "draft" form makes your work a little more relatable for me (relatable in this case is still relative though, something like how a Spitfire is slightly more relatable to the Wright Flyer than is an F35).  It's looking incredibly good.

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Excellent result with the resin prints, the fit is superb. I want one!!!!

Re the blade droop, which Crisp has confirmed as non existent. We had the same discussion on the Lynx Single Type GB a few years ago. When Tony Cooke, then a member and Wildcat jockey (where did he disappear to?) went through the engineering aspects of blade droop.

 

Colin

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Even less reason for blade droop - even apparent blade droop - on a Lynx / Wildcat because the semi-rigid head means they don’t even hinge downwards with the blades in a straight line.  Wasps far less aerodynamically advanced, so blade tip fell under gravity on the flapping hinge, restrained by the droop stop.  But in both aircraft, if you take the head out of the equation, the blades themselves are stiff enough to stay straight as seen by the naked eye.

 

[There are enough Finbarr Saunders moments in that post to keep @CedB chortling for a year.]

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I have to say Tony, I'm very impressed at the fact your design work was so accurate that it all fitted together first try!

Would a simple lateral spar inserted between the cockpit floor and lower fuselage be enough to stop the twist of that part?

 

Ian

 

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Friday lunchtime and still some snow on the ground here, a fall which began at dusk on Tuesday with this pearlescent mass roiling in from the Atlantic on the last of the sun:

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A minute after the photo was taken that cloud fell upon us in kit form....

On 14/01/2023 at 00:46, mark.au said:

Tony, seeing some of the hard copy come together, albeit in "draft" form makes your work a little more relatable for me

Me too, in an odd kind of way Mark.

 

In the CAD-ether you have all these kind of formal problems about shape and volume which you're trying to reconcile with one another, but at that stage your work is still abstract and separate from you on the other side of the screen, as it were. It's like up until that point you've been holding a seance with the original photographs and drawings in order to call upon them from the past for information; whereas subsequently holding the designs in the palm of your hand as resin prints, they are now real and here in the world with you, even though the original aircraft may be long gone.

 

Thanks for your kind words, and forbearance of arcane replies.... 😁

 

On 14/01/2023 at 01:44, perdu said:

mmmm

😁

The last thing a pie ever hears....

On 14/01/2023 at 08:57, heloman1 said:

Excellent result with the resin prints, the fit is superb. 

Re the blade droop, which Crisp has confirmed as non existent. We had the same discussion on the Lynx Single Type GB a few years ago. When Tony Cooke, then a member and Wildcat jockey (where did he disappear to?) went through the engineering aspects of blade droop.

Thanks on all counts Colin: the sharing of experience/information on this forum is just wonderful. :thumbsup2:

On 14/01/2023 at 08:57, heloman1 said:

I want one!!!!

Don't suppose I could interest you in a 1/32 kit? 😁

On 14/01/2023 at 10:36, Ex-FAAWAFU said:

Wasps far less aerodynamically advanced, so blade tip fell under gravity on the flapping hinge, restrained by the droop stop.  

Am appreciating that observation more keenly than usual on the basis of what follows..... 

On 14/01/2023 at 15:00, Brandy said:

I have to say Tony, I'm very impressed at the fact your design work was so accurate that it all fitted together first try!

Much like 'real' kits, I've found that having some kind of m/f  locating pins/pegs/lugs is critical in making sure the right things go on the right way up/round. Amazing how quickly you forget how your own work goes together!

On 14/01/2023 at 15:00, Brandy said:

Would a simple lateral spar inserted between the cockpit floor and lower fuselage be enough to stop the twist of that part?

This is indeed as very sensible suggestion Ian but I do suspect - especially at this scale - I would end up with the floor contracting around the spar as it cured. I had similar issues previously on the front firewall of the Vixen's engine bay, where it and the fuselage met at 90°. I think what I'll do this time around is to separate the cabin underside from the floor, thicken its (the underside not the cabin) walls and print vertically, as I noticed that the sheer bulk of the piece printed as a single unit had separated it from some of the supports when dragging up and down in the fluid, even when angled!

On 15/01/2023 at 19:20, hendie said:

Damn!   It's only January

On 15/01/2023 at 19:54, brianthemodeller said:

Aye, but I reckon we’ll still be going in March…

Only 300+ chiding days left until Christmas lads. Loads of time yet! :laugh:

 

Spare time over the week has ben largely spent being productively-unproductive: nothing new has been added to the build due to the need to carefully test if the Cadabstractions will actually work together as physical mechanisms - most pressingly in the matter of the rotors system when it comes to blade fold and pitch change.

 

The support system I designed for the main rotors did its job very nicelky: the individual blades snapped free quite easily from the vertical 'vees' upon which they were mounted for printing and remembering Alan's solution to curing long slender wings, I taped them flat on some old foamboard and left them to cure on a windowsill in the sun, turning after a few hours for an even tan:

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Rather stupidly I'd forgotten to add the opening for a brass spar down the length of the blades on tis occasion, but the the balde thickness makes them robust enough for testing purposes here. Once these had had sufficient chance to harden, it was out with a Tupperware tray of boiling water to see if it was possible to hand-build a slight twist into the blades. Not the easiest aspect to characterize in a single photo....

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As it turned out, this was not hard to do in a single instance, but keeping that consistent for all four means perhaps getting one right and then using it as the template for the others.

 

The original Flight article discusses the main rotor blades (manufactured by Westland at Yeovil, based on Parsons Corp. designs used by Hiller) in quite some detail, including them having both twist and taper. I think I mentioned in the thread recently that  leading particulars in the Wasps' operating data manual provided me with the chord lengths for each end of the blade in order to get them to the correct scale here. Angular data for blade twist though I can't find listed in any of my techical sources, so used several of the clearest photographic references to give a graduated 'tilt' downwards to the leading edge shown above.

 

From fiddling wiv the fevvers it was then inward to the blade extension/flapping link/spider hub combination ensemble upon which the notion of having an operant blade fold and pitch change quie literally, hangs. Finally having a smartphone with a decent macro facility means issuing the obligatory harsh close-up warning for the damper/link/hub arrangement:

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Whilst the fit is decent, you can see the first problem which  identifies itself quite resily when viewed from above:

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Yep. At 0.4mm thickness, the arms of that link on their own are going to be nowhere near strong enough in resin form alone to bear the weight of the outer blade sections, either static or being folded. Ditto that T-shaped protrusion to fit inside the blade extension and around which it rotated to change blade pitch,  in mimicry of the bearings on the real thing. Looking at a test fit of the whole ensemble from hub to blade extension, whilst the real life versions were of forged alloy, an awful lot is being asked here  of the resin to not snap off at under mild but injudicious pressure:

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This state of affairs naturally required a return to Fusion to begin work on some modifications.

 

I should add that I'm running two versions of the Wasp design in Fusion from this point on: an original 'core' version (which contains all the design work you've seen me doing over the course of the thread so far) that will continue until a full Wasp emerges, and a '1/24th modified' sub-version (containing any modifications required thus far in the light of test prints). Why two versions? Well, I want to preserve everything in the core version to later develop a 1/32 kit from (which will in turn come to require its own 'modified' variant), whilst the 1/24th modified variant here will contain current revisions necesary for this build alone.

 

Here's the basic idea then based on what I'd seen in the link/hub test assembly

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Based upon the maxim of 'individual problems will often require a change of medium' (which I just made up after too much coffee) the plan is to add a PE 'liner' inside the arms of the flapping link, in order to give greater strength:

52638692948_0be4bbd341_b.jpg

This in turn will be soldered to a length of 0.9mm brass tubing running oouwards though the flapping link (which you can see I've removed the original t-shaped extension from) outwards along the core of the blade extension to join a similar PE liner being used in those splayed 'fingers' which actually hold the blade in place

 

A side view of the current parts in assembled form, with the newer brass elements sketched in:

52638609774_ed7d0f8314_b.jpg

That should  - at least in theory - give a solid core to that whole run of features whilst at the same time minimizing any flexure at each end which would result in smaller parts snapping off. The brass insert for the outer  fingers you'd already seen me do in a previous post. The PE liner for the link should be mostly hidden from view so not distracting from the authenticity of the appearance in this area:

52637702342_0273a92563_b.jpg

With a blade added, despite being 1/24th scale you can see just how precarious the whole resin-only approach looked when put together:

52638653620_9fd2b21205_b.jpg

This is a good view to show additional problems with the blade assembly which need to be overcome as well:

52638214096_8d9796983b_b.jpg

To help avoid having the resin of the droop stop on the hub rubbing away over time and failing, I included a recess in the above hub/link modifications which it would act as limiter to downward motion of the brass insert which sits into it:

52638471564_f0e611a9fe_b.jpg

Whilst not an authentic feature, this inset should be largely invisible to the naked eye whilst at the same time providing much needed physical reinforcement to the assembly.

 

The other main issue visible above is the way in which you can see that the biggest reason blade currently drops down at too acute a negative angle is  because of the loose way it is held between the attachment pin locks. I'm less worried by this latter issue due to the fact that  the current gap there is an expected result of space being left for the brass strengtheners to be inserted. Once installed, as well as strengthening the pin lock area they should ssimultaneously function as packing to eliminate the extreme levels of play seen here.

 

One piece of good news to emerge from test fitting though is that the design of the pitch change bearing inside the blade exension seems to work well when the pin is released and the blade is folded backwards:

52638692933_8a35d68958_b.jpg

That photo also gives a better view of the current gap inside the locking pin area that will be elminiated by the brass insert.

 

Although I haven't test-fitted the arms for the pitch change spider yet , I'm 98.234% convinced from looking at the printed parts that my idea of a resin 'elbow' at the bottom link joint is a fabulous conceit that will not work. Because of the level of play required when the blade pitch changes as seen above, I'll need to build the spider arms themselves entirely from brass, with a working joint that allows for this level of motion. My resin version would just ssnap at the elbow on the first outing. 

 

A healthy crop of problems to resolve then before moving on but the good news is that none are exactly unexpected if a set of fetures like this have to actually work, rather than be posed in purely static form. I'll develop some more of the design revisions discussed here then,  get a fresh print of the smaller parts output and then try integrating them with some brass mockups. Only once I'm convinced this lot are an operational reality will attention shift elsewhere. Bit, teeth, between, & etc.

 

Happy Friday and may none of your bits be blue.

:bye:

Tony

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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Lots of problem solving going on there, Tony - I like that! :clap: 

 

Almost time for some paint, is it?

 

:rofl: 

 

OK, I said that to anticipate anyone else from taking the easy shot at me, alright? :D  :D 

 

Ciao

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4 hours ago, TheBaron said:

that cloud fell upon us in kit form....

I like that.

 

5 hours ago, TheBaron said:

those splayed 'fingers'

From memory (Very much not infallible) would fork end(s) be a better term?

 

Another epic update, Tony. Some very erudite thinking on the theme of strength going on. Also your idea of having two (or more) versions of the build.

 

5 hours ago, TheBaron said:

and may none of your bits be blue.

It's not quite that cold. Unless, according to Mr Connolly, you happen to be from North of the border. In which case it's a natural state.

 

Print and be damned Sirrah!

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It's just a pity Elegoo haven't got around to developing a metal printer just yet.  (I'm sorely tempted by the Jupiter though)

 

Have you thought of adding brass casting to your ever expanding skill set Tony?

 

I'll throw this out there just because... do you need to have an actual working blade fold mechanism? Or  one version with blades folded and one version with blades spread? And provide both versions in the kit.  Is the hill worth the climb?

Personally speaking I would build one or t'other but I doubt I would ever change the display between the two.

 

 

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