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TheBaron

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  1. Morning all. That's the Introduction finished then. Chapter 1. Despite all that appearances might conspire to suggest, work has in fact continued on designs for the Wasp over the past months and weeks, though out of a range of circumstances, two quite specific modelling factors have impacted upon the rate of progress. The first of these factors stems directly from having received a couple of requests from individuals elsewhere on the web wanting to purchase copies of this kit in 1/24th scale (aside from a 1/32nd version already promised here), such an issue necessarily requiring some earlier design decisions relating to the tail and cabin areas be re-examined from the point if view of somebody else having to manageably build one. Secondly, there was also the non-trivial question of having to build the means to vacuum-cast aluminium parts. I'll come back to the latter process later - it makes more sense I think to report on how the work has changed chronologically in the interim. Some time back I'd planned on leaving the aircraft skin 'clean' of rivets here, said features being added later using Archer's rivets in emulation of @Ex-FAAWAFU's glorious Sea King fantasia of legend. This notion has been summarily sent to feed the dust. Although Archer's have ceased trading but with Quinta apparently stepping in with a far more affordable alternative set of rivet layouts, the anticipated complexity of these designs in final kit form (as well as the expense of someone having to buy that many rivets to add as aftermarket) didn't strike me as a fair bargain to the Wasp-hungry, so felt I felt obliged to add these to the airframe myself as part of the printed detailing. Sanity be damned. Only the tailcone and boom have received such treatment so far, to whit the results of several thousand purgatorially-produced rivets now visible along the flanks: The asymmetic arrangement of maintenance access panels (the preponderance of these being along the port side) rendered this a much more prolonged task than simply creating the rivet formations on one side of the aircraft and subsequently mirroring them across to the other: Quite how much of that will be visible under BlueGrey in all but the most oblique of lights only time and pigment will tell of course - here's the somewhat more straightforward starboard side by contrast: With a tailcone able to be open or shut: There is another<collective noun> of rivets arrayed on the opposing faces of those sections that again were delightfully non-identical enough to stop you just mirroring the patterns from one side to the other: With a rather intimidating number of parts already in the design library, it made sense to actually finish off the rear of the aircraft before procedding forward again to the Nimbus and engine deck (lest crucial details get overlooked) so I set to work on the tailplane and rotor. With these two features at right angles to each other back there, any errors in one would be magnified by the other, so having @Anthony in NZ's measurements of such features cross-referenced with leading particulars in the maintenance manual meant being able to lay out the required dimensions with confidence in advance of creating the parts themselves: Not of course forgetting to check that said windmill doesn't meet the bigger one at the front in an unholy shattering of rotor blades and dreams... Much like cleaning a child's face, one you start adding rivets to one bit, of course you have to do the rest: Conforming to that modelling maxim that 'from afar 'tis fair, in proximity, is far from', the tail rotor had a surprising number of complex shaping tasks required to get the hub and blade mounts right: In printing terms that will I think need to be produced as three seperate parts in order to avoid 'support-acne' bedevelling those nice smooth surfaces. To wrap up this section then, renders of the finished tail assembly: At the start of this update I mentioned the need to learn certain aspects of metal casting for this build. The two specific areas of the main rotor assembly requiring metal parts are outlined here: As you can see, the two weak points concerned are the forks where they actually grip the blades, and the pitch change arms (inverted 'C' shaped features attached to the rear of the blade extension and the arms of the spider arriving to meet it from below). For the combination of strength and lightness it had to be aluminium/aluminum ('the Transatlantic metal') used in this instance. All well and good of course but I had to learn to do lost wax casting to achieve this, and, as the expense of buying kilns and furnaces was out, that also meant I had to build the means to cast myself (along with the inevitable experimentation with materials which such processes always require). I won't belabour the details here (though if anyone would find it useful for me to post details over in the 'techniques' section I'm perfectly happy to bore you to tears at great length there 🤣) but after several weeks I had a working gas furnace recycled out an old Calor cylinder with its middle section removed to reduce it to the required interior volume for the kind of casting jobs I needed to do: Despite the Heath Robinson nature of the undertaking, 'Old Hades' here reliably gets to over 800°C - well in excess for what aluminium casting requires. Gravity-fed casting alone though proved incapable of getting molten metal down into the finer parts of the pattern so I additionally had to learn to use vacuum casting processes as well in order to force the metal in to the required extent. To do this a cheap pump/chamber combination sufficed, which I drilled out and added some new parts to so that it could function as both vacuum chamber (for the investment) and vacuum table (for the metal pour). The results of this marriage between hope and instinct payed-off with a blade extension and pitch arm of the required material strength for the job: The surfaces of that first fully-successful cast still suffered from some gas porosity as you can see above, however such experiences have proven invaluable in giving me the means to now produce such pieces in volume with a much higher surface quality when fresh out of the furnace: A light sand and a polish should bring those up to requirement in due course. That's it for this instalment. Thanks for reading as always - there's a lot more CAD work to show in relation to the Nimbus and engine deck where the fuel and oil systems are now almost complete and the hydraulics have been started on. Again I've made some changes to the engine detailing/structure to account for others having to build copies themselves, so more on that next time as well. Until then, Tony
  2. Good to have you back Massimo! 🫂 This is unlikely to be uninspiring on mulitple levels.... 😁
  3. Looking great already Steve. It'll just be pure coincidence when you do then I guess.... 😁
  4. Both the virtual and physical versions looking very nice here indeed Loren - some exquisite surface detailing in that nose bay print, and those seats too developing very purposefully. A real burst of nostalgia in those screenshots in that I cut my teeth learning CGI workflows with Lightwave back in the mid 90s. How do you find it's modeller side for CAD work?
  5. Enduring mementos of an earlier self, captured by sublime skill in the present. Congratulations on two works of such delight and precision Steve, a truly, truly memorable build.
  6. Quick update today on revisions and additions based on the initial test print. Almost tempted me to get out the airbrush to prove you correct Giorgio! In fact I had rather an alarming paint-related experience during the week in fact when my old compressor - quite literally - blew up in the studio! Sounding like a gunshot followed by demented hissing from under the bench it scared the bejayzus out of me: the culprit a tiny corroded hole by one of the leg welds on the tank. Being almost as as expensive to buy a replacement tank as to get a whole new compressor outfit, I managed to pick up a deal on one of these Airgoo jobs as a replacement. Kind of you Pete: when curiosity drives you into unfamiliar and challenging circumstances on a build is when it feels most worthwhile. There are no discoveries to be had in following convention...in spacecraft as in all things! 😁 Don't tease you wicked man! 😁 No, of course there's no need. 😁 I'm simply enjoying the challenge and discipline of being able to express things at 1/24 which simply wouldn't be possible to attempt on a more diminutive basis. I follow a number of Japanese modellers via social media who produce work of such intricate beauty in terms of working features that I can only ever hope to produce a pale imitation here. The playfulness and invention they bring to their work just makes you want to smile out loud. An actual kit version of the Wasp at 1/32 won't allow such things of course, so a two-version assembly for the rotors/hub hub is, as you say, the most natural route to follow on that particular occasion. This made me laugh out loud for no readily explainable reason Pete! There's a Spike M. sketch there I'm sure.... You know you've got my attention in a big way at that Steve. I have some small bits to put on in the week so I'm doing to try a low-temp. test along the lines you outline there: much apprecaiate the info. I certainly recall having problems printing the Vixen fuselage in the very early days with cold resin which was why I've been paranooid about temperature ever since - that said though, I could just as easily have forgotten to shake the bottle before use... You're going to bill me for that, aren't you? That's most kind of you Colin. As a rotary novice (no way in heck am I going to use the word 'virgin' with this audience 😁) it's been quite a learning experience coming to understand (in even the simplest of terms) what the various part up there are and how they function together. Alan and Colin: I don't know whether to bless or curse the pair of you but I am going to seriously investigate this possibility. Sincere You meant 'arm' there Colin and not that there's an 's' missing....? 😁 Amendments to print designs then. In terms of the cabin, nose and roof area, I gavee some thought to the related issues of print strength/warping and breakdown of parts for printing. In the first instance, where there had been buckling issues with cabin floor and underside, after thickening both features by 0.5mm I followed the basic box-girder layout of the actual Wasp by adding x3 longitudinal beams under the cabin: In terms of printing, instead of the combined mass of the cabin/roof/nose (incorporating the extensive yet delicate roof sill) I'm going to break this region of the Wasp down into two main components for printing, first the crew accomodation floor and underside as a single unit, with door pillars: Complementing this is a combined nose/roof section: This only produces a single seam line to deal with during assembly where nose and undesride slot together, whilst leaving maximum unobstructed room for supports and resin-flow through the structures during printing. It's not evident in the above shot that I also strengthened all the roof framing around the top by increasing the diameter of the tubular endoskeleton around the inside of it by 25%: This doesn't affect external appearances but does give a much needed increase in rigidity for the glazing to be applied in particular. Thinking ahead to any strain on the combined structure when this thing is sitting on its undercariage at the end, I wasn't happy with the minimal 'tongue and groove' slot I'd previously rigged as a way of joining the cabin rear to the engine deck. This has been improved by continuing those longitudinal beams backward from the cabin, piercing the front wall of the deck and emerging into the region where the autopilot gear and pitch control rods normally sit on the real thing: Mounted on the the reverse face of the cabin wall, that plate above the beams should trap them against the floor, helping resist any strain on the join between cabin and deck when sitting out on her pins: Satisfied from having a physical print of the main blades in my hands that the trailing edge was going to be up to the job, I added in the two trimming tabs, to be made from PE on grounds of thinness: Not feasible to slot the brassware into the trailing edges, so I've cuts slots into the blades for the tabs to sit into: Also revised in Lychee, prints for the revised hub/link/extension assemblies incorporating changes shown in the previous update: I'll give that a low-temperature print as Steve suggests, to compare against the initial batch done in the mid 20°C s.... Looking back that wasn't such a quick update. Sorry, I lose track.... Take care of ypourselves until the next one. Tony Update: this came in as I was about to post: Madre de Dios but that's awesomely generous of you Mike! Betwen Alan and Colin's suggestion and now this I have some serious investigation to do. Thank you so much - I shall certainly be in touch!
  7. Didn't you though? And have to say I think your instincts were spot on Bill - bang! - suddenly that pulls the whole thing together. Joyous work to behold.
  8. The inundation of comments speaks for itself Steve in terms of how much esteem we collectively hold your work in here. Less a benchmark than some kind of new altitude record in terms of quality. Congratulations to you. 🤝
  9. To call this thread gloriously unhinged would doubtless be to risk inciting an outbreak of hinges. Never in the field of human decor can so much have been applied to so many parts of an aircraft by so few....
  10. 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: A minute after the photo was taken that cloud fell upon us in kit form.... 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.... 😁 😁 The last thing a pie ever hears.... Thanks on all counts Colin: the sharing of experience/information on this forum is just wonderful. Don't suppose I could interest you in a 1/32 kit? 😁 Am appreciating that observation more keenly than usual on the basis of what follows..... 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! 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! Only 300+ chiding days left until Christmas lads. Loads of time yet! 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: 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.... 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: Whilst the fit is decent, you can see the first problem which identifies itself quite resily when viewed from above: 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: 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 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: 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: 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: With a blade added, despite being 1/24th scale you can see just how precarious the whole resin-only approach looked when put together: This is a good view to show additional problems with the blade assembly which need to be overcome as well: 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: 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: 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. Tony
  11. Snap! 😁 Thanks Chris: I'm sure I can add to that list in due course. 😄 Thanks Giorgio. There is something genuinely satisfying about the process - even discovering which bits didn't quite work! 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?
  12. 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': Ta Nige. Thanks CJ. 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! Kind of you Zac - my thanks! Don't suppose you've got a spare McTaggart Scott deck winch to help me manouevere this monster around the bench Crisp? 😁 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.... Dangerously close to mincing an oath there Terry! 😁 😁 You're a very kind man Brian. 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.... I see a 1/24th scale triplane in your future Alan.... Gracious of you Colin - thank-you! 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. It's a shake-n-bake Wasp.... I'm less scared of it today Pete now that I've seen that some of the bits do fit together as intended! Strong Hugh Grant vibes here Keith. 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.... My compliments to this fine woman upon choosing such a discerning husband.... 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: 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: 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: 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: 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: 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: 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: 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: 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: 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: 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: 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: 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: 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: 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... Benisons upon your modelling. Tony
  13. 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!' 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: 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: 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: 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: 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? 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: Similarly feelings too at handling the main rotors: 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: 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: 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: The quality of detailing on the MRGB exceeded my expectations as a printed item: Ditto with the front and rear of the reduction gearbox, which were equally sharply delineated down to the last bolt: 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: 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: 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.... 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: Uncured resin like this always looks a little waxy but I'll get some UV on them in the next couple of days: 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: 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. Tony
  14. Impressive and sensitively deployed levels of filth - congratulations on another top piece of work Chris.
  15. I now it's still a wip but whatever you've been doing to shade those panel lines Anthony has a sensitivity of variation about it around the airframe already!
  16. Those are surely alien heiroglyphs, not sensible sprues! That wing arrangement looks like it should have David Niven sitting on it... Good luck with this quixotic blend of aeronuaghtiness you two.
  17. In the absence of surrounding objects, the visuals on those two are so good Steve that they sit aloof from any particular sense of scale. Remarkable replicas, quite, quite remarkable. Safe travels, both horizontally and vertically....
  18. Inching towards getting the first print on later in the week, due to most of the famille currently stricken with lurgey of various kinds... Digging back into the thread for some info on scaling the other evening, I came across this prophetic post from Alan back in mid-November Boy is he right. On the standard Mars 2/3 printer, at 1/24 one half of the cabin alone eats up the entire plate area! Rather glad of the investment in the Saturn 2 at this stage as it simply wouldn't be feasible to work with resin at this scale any other way. I usually avoid running beta versions of software for anything mission critical but as the latest one for Lychee introduces some potentially useful new features, I decided to give it a punt for the cabin & nose section test: Every time I do up supports like this it reminds me of the old Wild Mouse rollercoaster at Littlehampton back in the 70s. If the wind was in the right direction and you were sitting at the back, a blizzard of fag ash used to hit you in the face on the way down the big drop.... Although I had anticipated the issue, it's still something of a shock to see the sheer volume of print supports required at this scale! Thankfully, along with the existing 'paint support' functionality, Mango have a new 'inline' tool in the support interface of this beta, one which allows you to automatically generate lines of supports along a given path - an absolute godsend at the larger scale. Another size-related function I didn't really have to have to worry about too much previously at 1/72 was that of suction. With the parts here physically occupying such large volumes of space at 1/24, there's a very real risk of the final print emerging distorted (or just as serious, pulling away from the FEP) during printing, resulting from the push/pull effects of such massive items moving up and down in the resin. The latest version of the software now contains a suction analysis tool which helped here with orienting that main cabin/nose component in such a way as to avoid the hollow space between cabin floor and bottom of the airframe setting up a potentially problematic drag in the print fluid. It took a bit of spare time getting to know these new functions here so next time out it should hopefuly be a bit quicker. One final thing which I know I'd promised @Anthony in NZ I'd look at is the effects on detail of producing the Wasp in 1/32. To this end I knocked up a quick size comparison whilst Lychee was open using the MRGB as a litmus - you can see the size differences visually here: In terms of physical dimensions, approximate heights of that MRGB are then: 1/24th = 20mm 1/32nd = 15mm 1/48th = 10mm Given those value I reckons that some of - but by no means all - the detail on that component would be preserved by the print resolution of the Saturn 2 down at 1/32, but by 1/48 it will have vanished. When I set that piece up for a print then Anthony I'll include a 1/32 version as 'ground truth' for you to eyeball. Oh what a world of possibilities....😁 Hope your Sundays are going Ok. Off to light the living room fire now as it's already dark and cold at lunchtime. Tony
  19. Are you sure you're not living a Benoit Blanc movie for real over there Anthony? (Lucky devil - that view from the deck looks fabulous!) PN's have been enormously helpful but confirmation appreciated on following: 1. Are naval helicopter pilots a breed apart? 2. Flap and droop stops limit vertical motion of a blade whilst snubber struts restrict lateral motion? (i.e., these three operate in concert to ensure blade stability?) 3. Daft question on the tailplane - it is a fixed feature? (i.e. non-movable, or have I missed something in the controls?) Strong Stephen Maturin/laudanum vibes here Crisp. Have you checked on the sloth....? You're quite right right Bill. I haven't worked out yet what I want to do about them as resin will be too fragile in this case and I need to mull over the best way to insert such features as PE, for strength. With so much brasswork involved in proceedings already, another reason to pause at this point is a crying need to catalogue the existing metalwork and output them as unfolded designs. Not a task I enjoy quite honestly.... Once you notice them - they're everywhere! Not sure my neighbour should have one dangling from the underside of his Qashqai though.... Every day is Christmas Day on Britmodeller Steve. 😁 Am not entirely disinterested myself as it goes Ian! 😁 Nothing significant to report today as currently trying to get my wife's mobile number swapped over between phone companies and it's going about as well as you can imagine.... Tony
  20. 👏👏👏👏 That nose profile....flows superbly now. No other word for it Anthony.
  21. Ingenious method for enlarging that radome/nose Anthony - belt & braces modelling at it's very best. Is that a method you've used before? I find I hard to believe that photo of Queenstown is actually a real place - the vibrancy of that sky and water make it look hyperreal.
  22. It's truly damp and cold and grey and windy here today; one of those bitter January afternoons in which you idly wonder exactly where you went wrong in not reaching this point in life without possession of a tropical villa a la Ian Fleming. Mind boggled just now in looking up Goldeneye to find you can actually stay in it! https://www.theflemingvilla.com/the-experience/ No pricing so I guess if you have to ask &etc. etc.... Rambling back to the main business of the day though: After watching Glass Onion at the weekend (fabulous fun) I must confess to now covetting a fez Anthony and wanting to lie in the bath smoking cigars for days on end between cases.... 😁 Thanks Chris - the very same to yourselves over there. <Removes fez and places it on the bar> Don't like to brag Steve but I had several hundred hours in my log book by the time I was 12.... Spinning that rotor hub around whist working on it Giorgio I kept thinking I heard the The Blue Danube.... None needed Bill 😁 This whole whole last week or so has just involved walking a tightrope of how-does-that-work-can-it-work-at-this-scale, with no guarantee that there would be a positive outcome. Mercilfully Westland seem to have had future modellers in mind in making their structures self-evident once you clock what's going on - which is a far from immediate process in my case! 🤣 Watch me break parts during assembly.... 😬 I've had more enough tricksiness from this part of the Wasp Alan thank you very much; playing it safe and going for a vintage Airfix-type solution to the problem. 😁 (There is, as always, an elegance of purpose to your suggestion but I fear that threaded approach is out of my league) More than enugh Ian! That's characteristically kind of you kind Adrian but the most that I'm doing is just joining up the dots from visual evidence - I really miss @Ex-FAAWAFU not being around when it comes to experiential knowledge of flying these things. It's a pale substitute but there is this 1982 gem from the wonderful Horizon series' that used to be on BBC2 back in the day. Quite without meaning to I got a bit carried away this morning and ended up building the main rotor blades. I hadn't intended to go that far but after working on the blade extensions I just decided it would be eaier to complete the job now, whilst details are fresh in your head, than to come back at a later stage having forgotten what was involved. I actually liked Alan's idea about having a blade extension setup that screwed together but in the end, a sense of my limitations kicked in and I went for something which Airfix might have used back in the 1960s, namely gluing two halves together to lock the part onto a central mounting spigot that allows it to rotate without slipping outward: This is basically a simplified version of the dual bearing system that sits inside there on the real thing so not an original notion. Outward of that feature you can see the way the remainder of this blade extension uses a square peg to attach the remaining length into place at the correct orierntation. Splitting that part midway means I only have to worry about tidying up a short pair of seams top and bottom when fitting those parts together, rather than along the whole length of that part. I've also revised the length which the brass reinforcing rod travels out from the spider so that it adds support in the critical region point where strain on the structure will be greatest. Beyond this extent, the part should be strong enough to handle the weight of the blade. The - I'm calling them 'fingers' - which each main rotor blade bolts onto tested my patience heavily last night, due to the manner in which they emerge and spread out of the flared ends of the extension forging: The struggle was mainly between the size and spread of those circular 'fingertips' top and bottom in relation to the angle at which the cone-like feature preceding it spreads out from the forgin. this led to a prolonged and tedious back and forth between both sets of features on the timeline until they matched what could be seen in photos taken from various different angles. Again part strength is a major concern here due to the effects of any undue pressure on those fingers when folding the blades back into the support cradle. As to the baldes themselves, well thanks to Anthony I had some ground-truth dimensions from measurments of an actual Wasp he so kindly conducted a while back, added to which I found some additional leading particulars in the Wasp performance manual. The original Flight article describes the blades as having both taper and twist so I was pleased to find actual dimensions for root and tip chord widths listed in the manual to help with the former. This, along with an accurate (non-drooped) figure for the rotor diameter let me first produce a dimensioned mockup using blanks in order to check that these figures all matched up with the overall dimensions of the airframe: With that investigated I could then build the blades for real - simple enough to using airfoil profiles at either end for a straight loft. From (predictably rare) nearly end-on shots of the blades, these airfoil shapes appeared to be symmetrical, something which I undertand is not unusual in helicopters? As to the twist in them, well, I can't see that in photos so am obviously missing something. It's not critical at this stage though as for the blade droop itself, I'm going to produce that after they're printed, softening them in hot water and forming them on a jig. If necessary I so can include a twist then if it's prominent enough to be required. At that stage also I'll insert the metal reinforing rod down their centres for strength: To minimize the risks of any damage to the blade mounting, I designed a PE insert that will fit inside the fingers themselves (in a hopefully unobtrusive fashion) to provide additional support for the weight and strain of the blades: Once decoupled from the pitch control spider, folding the actual blades back is a simple enough process of removing one of the locking pins from those fingers so that the remaining one on the leading edge side acts as a pivot. You know I had to give it a go. But had I left enough space in my designs for the butt end of the blade to rotate within the space between those fingers? By pure skill utter good fortune I had! Locked into place using metal pins and with that PE insert for extra strength, I'm pretty sure that should withstand modest downward pressure during use now: Folded back like that you can also see the packing blocks top and bottom of the blades which provide parallel surface to locked inside the blade extension for flight. Duped around the transmission axis: Undersides: Closer: Avec chassis: Amazing how with the rotors on it suddenly starts to look like it could fly! Renders unto Caesar: Calling this one 'Dawn off Portland' as I like the way the light strikes the blades: Anyway with that lot done it's time to take stock of the parts inventory: Excluding large parts of the airframe and engine/oil system, I've been slowly adding smaller features to the .stl library and have such a number now at this stage that I probably need to start some test prints to ensure that my guesses on some of the finer tolerances are going to work out as physical objects. The major oil pipe runs will need something custom done in Fusion in the support line due to their length and fragility, whilst the Nimbus I might have to split into at least three sections for printing purposes. The MRGB I might get away printing as a single object supported from below - we'll see how that supposition works out in due course. This is probably a god point then to pause the design work in Fusion then and spend any free time over the next wek or so putting together support structures for the first major print test(s). As with the Vixen, this won't be to start building the actual model but to act as a testbed to identify any unforseen problems with either printing or assembly. In contrast to today's gloom, yesterday the rising earthshadow was outrageously pure in colour at dusk at dusk: Adieu from the shade mes braves. Tony
  23. Crisp and colourful work Julian - congratulations. Two excellent Buccs!
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