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Author Topic: Hawker Tempest II, 1/24 scale rubber power.  (Read 9734 times)
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Prosper
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« on: June 01, 2014, 05:44:37 AM »

Hullo everyone,

For some weeks now I've been working on a Hawker Tempest II model, 1/24 scale for rubber power. It's proving (mostly) less troublesome than the Fw 190D I made over the winter - but there's a lot more of it! Also I've decided to use pendulum-controlled ailerons, which adds another layer of complexity. I didn't start a 'build' thread because I was too cowardly, but now I've got to a stage where it looks like it might actually progress to completion (gasp), so I thought I'd start a 'retrospective' topic.

The original drawings are Arthur Bentley's - extremely detailed and with an air of authority about them. I haven't come across any inconsistencies so far, despite having been researching this design for over a year now in odd hours here and there. Sometimes just a cursory study of photos of an original will demolish any sense of trust you might have had in someone's published drawings, but not in this case.

I've gone for what ought to be a sturdy design, but it's all TLAR, so I may have misjudged the strength needed, or failed to spot a critical weakpoint. Assuming I manage to finish it and am strong enough to throw it (I'm working on my dumb-bells), it will be by a large margin the biggest model I've flown. Bf109 wing area 280 cm2, flying weight 23-ish grams. Fw190D 317.7 cm2, 30-ish grams. Tempest 486cm2, estimated 40-something grams.

I'm going to break up the 'back-story' into separate posts. This a.m. I've been doing some dry-runs before assembling the stick-and-former fuselage framework, and it occurred to me that since the framework was hanging together without glue, I could mock the rest of the bits up around it. It just held together long enough for a couple of photos, then fell apart!

I've made plenty of foul-ups already, some just down to clumsiness, impatience and bodgy workmanship, some because I'm trying new things, which don't always work out. Some because making model aeroplanes is difficult Tongue.

Stephen.
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Hawker Tempest II, 1/24 scale rubber power.
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Prosper
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« Reply #1 on: June 01, 2014, 05:49:11 AM »


The Tempest was physically comparable to the Republic P47 - about the same size and power. The performance characteristics were very different though. The Tempest II never flew in WWII combat because despite having first flown in 1943, and being generally superior to the Sabre-engined Tempest V, there weren't enough Centaurus engines to get production going. By 1945 they were being churned out and the Tempest II was slated to go to South East Asia to help roll up the Japanese, but things ended sooner than expected, mostly courtesy of two B-29s.

Here's a picture I took of LA607 with my Kodak Instamatic in 1972, at Staverton. The Ford Capri wasn't my dad's - he was more of a Cortina Estate type of dad! LA607 was the second prototype Tempest II, and ended up with Kermit Weeks in FLA, last I heard of it.

The Tempest is a very handsome object to my eye but the gurning chinny-chin-chin of the Sabre-engined models rather detracts from the look, for me. I was going to opt for a Mk V, because the chin is a great place to mount a pendulum, but I thought, naa-aa, build what you want, and cram the pendulum in anyhow Grin. What's more, the radial engine nose is slightly longer, and I thought it would be more straightforward to build (I was wrong there). If this flies I'll probably make a Tempest V, maybe invasion stripes and whatnot, in the future.

I've chosen to represent MW800, because according to an artist's impression "off the internet" it had a red spinner. It was an early example, built in 1945. Here's a pic of some of its close relatives. Y'know, it occurs to me that whoever took this picture in 1945 was a bit more skilled than I was with my Instamatic; whadya think? Smiley.

Stephen.
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sparkle
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« Reply #2 on: June 01, 2014, 06:56:43 AM »

 Grin Nice work, Prosper! I've built one of these, not as tidy as yours, but I do prefer your full metal look.
   I believe my father used to work on the engines on these in occupation forces in Germany. sadly he is dead and I never asked him enough questions.
   As always I look forward to watching your progress.
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Don McLellan
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« Reply #3 on: June 01, 2014, 12:55:45 PM »

Another exceptionally beautiful model Stephen!  Very happy you're sharing your progress.
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Prosper
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« Reply #4 on: June 01, 2014, 01:34:03 PM »

Thanks Don, thanks sparkle Cheesy. Yes, always sad to think of the experience, knowledge and insight lost when people die. Mind you, decades ago I knew a bloke who flew Tempest Vs in the war, I used to ask him questions - but he didn't want to talk about it!

I began this build with the wings - thought they'd be the most difficult bit (correct, so far). I took a lot of step-by-step photos, because I think I might have settled on a sequence of wing-building that would suit many or most wings made of aliphatic or cyano-coated balsa. Don't worry, I won't bore anyone with the whole lot!

I used aliphatic with silver (i.e. aluminium powder) pigment added instead of white. I've got quite a bit of the white sheet left over, so the rest of the airframe's white. I also tried scribing panel lines on the flat sheet, prior to assembly. This brings its own problems of precise registration of the wing skins during construction, but if I can learn to get that right it's by far the easiest way to do things.

The wing section is Hawker's own, 14% thick at the centre-section tapering to 10% at the wingtip rib. It looks symmetrical but isn't quite. It's a section with a small radius leading edge, and this meant that I could use flat sheet and not skins that had been wetted and bound to a mould to pre-form them, because the skins don't undergo much curvature (the grain of the skins runs fore-and-aft; they don't want to bend much).

Rather than the prefab spar sheet I used for earlier efforts, I thought I'd better make each spar individually, a lighter approach for deep spars. I worked out a method which is quick and easy, based on the fact that the spacing and verticality of the uprights isn't at all critical - in other words, just fix the uprights any old how, no marking, measuring or left-a-bit, right-a-bit Smiley. The uprights are fixed each end with a small drop of thin CA run in by capillary action, and trimmed later. The tail uses spars made from prefab sheet, just the same as I used for the Fw190 and Bf109.

The two ribs and the spars are then fixed to the bottom skin and the top skin is glued on with aliphatic, which gives the longer working time needed for the job (there's plenty of left-a-bit-right-a-bit going on). I sat the bottom part in a crude cradle in order to get the washout right - trouble is the cradle was too crude - the port wing ended up with a couple or three degrees of washout, not wanted - I had then to give the right wing the same washout. I can't see from photos or the drawings that the original had any washout, and I'm not a fan of the stuff.

Before fixing the top skins on the main wing panels, I installed the pushrods and bellcranks for the ailerons, and also the landing / ID lights. The lateral pushrods (1/16" sq) now stuck out until the wings were joined - with all the work left to do it was amazing that I got through without snapping them off with my normal Mr Magoo type clumsiness. They also meant that I couldn't give the wingrib a final facing with a sanding block to render it completely flat, so the mainwing/centresection joints suffered a little.

More shortly!

Stephen.
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tom arnold
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« Reply #5 on: June 01, 2014, 03:03:34 PM »

Beautiful job, Prosper. We had a fellow here fly a Tempest II at Geneseo and it was a good flyer and eventually went missing in action after a mission at Geneseo one summer. His had a smidgin more dihedral than scale and the pilot admitted it was a bit on the edge on windy days. What sort of pendulum system are you planning on? A vertical or angled-horizontal one? And a construction question too: why was the grain of the wing skins chosen to go chord-wise vs. span-wise? Many thanks and looking forward to seeing this build.
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Prosper
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« Reply #6 on: June 02, 2014, 04:32:01 AM »

Thanks for the encouragement Tom, and the questions. Seems like your friend's Tempest II needed a D/T, huh? That seems to be the way of it in the FAC/Geneseo style of scale-model building, as far as I can make out Grin. My first target will be 5 seconds Grin.

The pendulum will be near-vertical and as far forward as I can get it. The slight tilt is not due to any fancy theory of operation, just down to getting the thing to fit in a way that doesn't (I hope) get fouled by the rubber motor Smiley. As you can imagine the pendulum will be very short, pivot-to-bob distance, and this leads to a very twitchy action. If you cause the pendulum to move by yawing the fuselage quickly from side to side, the pendulum swings in a very excited fashion and takes a few cycles to damp down. A long pendulum would react less and damp better, I imagine. I made a simple, non-scale S&T test model last year and that worked. Whether this bigger effort will work is questionable though. The ailerons are much heavier than the ones in the test model. They'll have much geater aerodynamic forces acting on them too. Against this, the weight of the Tempest's pendulum will be greater than the one in the test model. Another consideration is that once you've glued the wing skins up, it's sayonara to the bellcrank/pushrod mechanism! If any friction develops due to bad construction, that's it. To get at it would need major surgery. . . The Tempest has some dihedral. If the ailerons don't work perhaps I can hope that it could fly large circles in very calm air and over long grass!

The grain runs chordwise as a convenience more than anything. I find the prospect of making ribs for tapered wings very off-putting. I know they can be made by sanding rectangular blanks squeezed between a root and a tip template, but this never seemed accurate enough to me, and it doesn't work for elliptical wings. I know you can put spacers between the blanks to increase accuracy, but by then you may as well make a whole solid wing from balsa or foam, and slice it chordwise to get your exact rib profiles. Using chordwise grain and several spars needs just a root and a tip rib to define an exact aerofoil section. The method seems much quicker and easier to me and hasn't (yet) shown any major shortcomings in flying/crashing. . . When I make a DHC2 Beaver or suchlike wing with constant chord and thickness, then I'll try ribs and spanwise grain, and see how the two methods stack up.

Regards,
Stephen.
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Prosper
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« Reply #7 on: June 02, 2014, 04:35:20 AM »

I mentioned landing/ID lights - the Tempest had a red and a green lamp in one bowl under the stbd wing and a retractable landing light under the port. I reshaped the end of a Sharpie pen slightly and plunge-moulded two reflector bowls from thin transparent plastic sheet stretched between two battens. This was quick because no female mould or cutout was needed. I painted the outside of the bowls with silver paint and trimmed them to shape. I cut lenses from the same thin sheet and glued them into place in cutouts made in the wing skin. This was hard because I just couldn't see the tiny transparent discs most of the time! Then I glued the bowls on the inside. You can see the Sharpie pen influence in the last pic Smiley.

Stephen.
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sparkle
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« Reply #8 on: June 02, 2014, 07:57:47 AM »

 Grin Thats mad detail!
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billdennis747
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« Reply #9 on: June 02, 2014, 09:21:31 AM »



The pendulum will be near-vertical and as far forward as I can get it.


I always enjoy hearing about pendulum experiments but I don't think vertical, side to side pendulums work. Fernando Ramos showed this. As a model tightens into a turn, the pendulum will swing out and it's time to collect the bits in a bag. I suspect the tempest will fly anyway. I'm interested in why you didn't go for a shallow-angle pendulum as it would fit better, could be longer and would have better mechanical advantage?
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Prosper
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« Reply #10 on: June 02, 2014, 03:25:44 PM »

Well the answers are difficult because it's based only on my no doubt half-witted ponderings. I can say certainly that an inclined, long pendulum is as much of a problem in terms of rubber motor fouling as a shorter, vertical one. You still need the pivot to be well above the bottom of the fuselage. As for centrifugal v. gravity the more I think abut it the more speculative it gets, but it helps me to recall that I made a vertical-pendulum test model last autumn that made long flights with no dihedral at all, a low-winger.

A canted pendulum simply cannot refrain from doing the wrong thing in any significant climb, or dive, depending on which end is hinged. A vertical pendulum though just becomes less lively as climb or dive angle increases.

Without a linked rudder, a pendulum controlling ailerons is just a wing-leveller (or to be precise a bank-angle maintainer). In a steady, balanced turn the vertical pendulum is central, i.e. on the aircraft's vertical axis, so it's doing nothing. The essence is in how fast the ailerons can react to any gust-or-turbulence induced excursion in roll. If they can react to restore the trimmed bank angle before the roll causes a new rate of turn, i.e. before it's muddled by a change in centrifugal force, then you're winning, and a vertical pendulum will react faster than an inclined one. I'm not saying it'll be successful in restoring the bank angle, just that it will try, up to the point of full aileron deflection. If the turn is a flat (skidding) turn, centrifugal force will swing the pendulum in the direction which causes into-turn bank, i.e. it tries to restore a balanced turn. If the turn is a slipping turn, again centrifugal force will move the pendulum in the sense that picks the lower wing up, tending to restore balance.

An inclined pendulum will respond to slips and skids likewise, only I imagine more slowly. It will also be centred in a balanced turn, if I understand aright. But in the case of picking up a dropped wing before the bank induces a heading change, I believe it's in trouble. No heading change no centrifugal force change, so the inclined pendulum will just swing full-deflection, but ponderously because of its length and inclination. In other words it will react slowly, but overreact completely.

As a model tightens into a turn, the pendulum will swing out and it's time to collect the bits in a bag.

I presume that by swing out you mean the pendulum will be affected more by centrifugal force than by gravity, thus actually causing an into-turn aileron deflection? I'm still not sure that the pendulum will go past the vertical, in other words it will swing to where there's no aileron input and the model's in the same situation as a locked-control model. certainly that's a dire-sounding situation for a heavy low-winger with little dihedral and a huge vertical tail area!

I suspect the tempest will fly anyway.

I suspect so too, but it needs to fly for a decent spell. Instability is a duration-killer. In layout and dihedral it's remarkably like a giant Chilton DW1 - but with consequently greater inertia forces, also greater wing-loading, and the lack of dihedral-enhancing trouser fairings. The dihedral on most WWII low-wing fighters seems adequate to me, but the Tempest is pushing it really hard IMO.

These are just my musings, I'm hoping to hear from anyone who can correct or add to the above.
Stephen.
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tom arnold
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« Reply #11 on: June 02, 2014, 10:27:22 PM »

I think Bill was quoting from an article that Fernando Ramos wrote in the old Model Builder mag eons ago. He took a vertical pendulum "bread board" arrangement aloft in his full size airplane and had his passenger hold it in his lap and they observed it as he went into a diving turn much like a model will do. The pendulum bob swung to the outside of the turn due to centrifugal force immediately which (would have) increased a model's bank angle. In using a second arrangement with a horizontal pendulum canted down about 10-15 degrees and hinged at the front, it was not affected by the turn no matter how tight and always moved "down wing", so to speak. The pendulum was buried in the wing and was as long as the wing chord. His passenger, modeller Jack McCracken, then built a jumbo gas scale model of the Bellanca Columbia and it flew flawlessly and I witnessed many flights of it. However, it really did not need it but you could see the wings getting picked up at regular intervals as the system did its thing.

Having said all that, I do think a vertical pendulum would work in the beginning of a wing low situation and if it worked early enough, the turn would never develop. If the turn develops, though, well......
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Prosper
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« Reply #12 on: June 03, 2014, 03:29:55 AM »

Ah, that's a very illuminating account Tom. With a front-hinged inclined pendulum, he's trading gravity against centrifugality in that one condition, a developing spiral dive. That's probably fair enough given the terminality of that condition in models with inadequate spiral stability, but I can't see how, with that setup and in a straight ahead dive of over 10-15 degrees, such as in stall recovery or glide entry, the pendulum won't go to full-stop one side or the other. The only answer would be to stay away from full stalls, and while advisable, that's not easy for models with small tailplanes, or flying in a breeze, or while trimming, or flirting with CL max to go for max endurance and scale speed. . .
 
Conversely, in a climb the aileron effectiveness of this same pendulum setup will reduce dramatically, so I don't know how it would work for a model that's tip-stalling in a climb (however if you're lucky it might sort things out in the subsequent spiral dive!).

If the turn develops, though, well......
I do regret not having opted for a rudder linkage in this model - I looked hard at it and it's not a very easy job. A rudder changes the whole story. I'd presumed on a floating rudder because of the huge fin area and small dihedral. We'll see how it works out. . .Smiley

Stephen.

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Prosper
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« Reply #13 on: June 03, 2014, 03:31:39 AM »

Grin Thats mad detail!

Well in fact these lights turned out easy to make, so didn't make me 'mad' Grin.

I went for navlites too. The only way to do it was to use solid plastic blocks (from a toothbrush handle). Moulding something to that extreme curvature would be very time-consuming, tricky and also fragile, I decided. Solid blocks are H-E-V-V-Y, just what you don't need at the wingtips, but they're strong, and placed just where a lot of whacks occur. I drilled out the inside face to represent the coloured bulb, and dropped paint into the inside of the drilling. The result looks great from some angles, but because the highly-curved plastic acts as a powerful distorting lens, from some angles the effect is of some lurid trinket from a Christmas cracker. After lots of consideration I decided that the pros outweigh the cons.

Stephen.
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« Reply #14 on: June 03, 2014, 03:35:24 AM »

Making the leading edge intakes was a faff. The drawings were a bit ambiguous and although I had fantastic photos from 'walkarounds' available on the net, it was hard to get the intakes right. Put another way, I didn't get them right Smiley. They're completely integrated with the wing and I found myself making them up as I went along, cutting out little bits of sheet and adding them to the wing skins with little balsa tabs and so on - result is a dog's dinner. I could re-do them but perhaps I'll wait to see if they get wiped off in a crash and then the decision will be made for me! These intakes convinced me that in fact the Tempest V would be an easier prospect - nice, clean leading edges and a dirty great chin intake that you could enjoy whittling from a big block without worrying about the weight.

Finally, I glued the mainwing panels to the centre section panels and braced the wings together. The mainwing/centresection joints aren't completely flush, as can be seen near the L.E. in picture 2. The difficulty in sanding aliphatic and the fact that the skins are only 0.3mm thick may lead me to accept this blemish.

After my experience with building an Fw190, where I decided to let the wing/fuselage join pretty much look after itself, and paid the price in terms of time wasted bodging the joint, I thought this one through, and the way the two mate is pretty accurate and sound. I just hope it's strong enough :-O. The weight of the whole wing assembly shown here is 11.2g.

Stephen.
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« Reply #15 on: June 03, 2014, 04:29:12 AM »

 Grin  really neat work. i seem to remember the air intakes were a bit of a mystery when I did mine. Watching this is making me think I should repair mine.
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Prosper
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« Reply #16 on: June 03, 2014, 05:42:24 AM »

. . .making me think I should repair mine.

You should, I've been reading the comments on Don McL's Stinson A thread, I think he's right, it's getting it down from the shelf that's the hardest part, then figgering out how to go about it, but once you start hacking, you're away! All balsa can be scarfed, spliced, butted, doubled, infilled or what have you. I admit that tissue repairs are a problem if you're hoping for a "nobody will know" look, but my covering skills mean that even a model that's just freshly covered looks like it's crashed in a thorn hedge Grin.

Stephen.
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« Reply #17 on: June 03, 2014, 05:51:53 AM »

Great work as always Stephen - fascinating to watch.

I'm still a bit baffled as to pendulums  Smiley since in a coordinated turn there is no centrifugal force discernible by the 'pilot' (pendulum) just increased G. I suppose you are using the slip condition before the spiral dive to give the aileron response? ie a left movement of the pendulum gives right roll?
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« Reply #18 on: June 03, 2014, 05:53:34 AM »

Next installment of the back-story, AKA "here's one I made earlier". There seems to be an awful lot of it, I'll be glad when I've caught up to the present. . .

The Tempest tailplane is disastrously thick - 14% thickness-to-chord - this is a real bummer in terms of weight and aerodynamics, but looking for something positive; it won't ever warp! The fin is thick too. The fin hasn't come out well - despite its thickness it has a pretty sharp leading edge and this caused fat-finger problems for me. Also the fin has to blend with the fuselage; I got this about right but I can see that when it's painted it's going to highlight a lot of unevenness.

Spars are cut from a large premade sheet of 0.3mm balsa with 0.3mm strips running across.

Stephen.
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Prosper
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« Reply #19 on: June 03, 2014, 06:15:09 AM »

Hi Jon, yes I'm baffled too. This is what I wrote yesterday.
Without a linked rudder, a pendulum controlling ailerons is just a wing-leveller (or to be precise a bank-angle maintainer). In a steady, balanced turn the vertical pendulum is central, i.e. on the aircraft's vertical axis, so it's doing nothing. The essence is in how fast the ailerons can react to any gust-or-turbulence induced excursion in roll. If they can react to restore the trimmed bank angle before the roll causes a new rate of turn, i.e. before it's muddled by a change in centrifugal force, then you're winning, and a vertical pendulum will react faster than an inclined one. I'm not saying it'll be successful in restoring the bank angle, just that it will try, up to the point of full aileron deflection. If the turn is a flat (skidding) turn, centrifugal force will swing the pendulum in the direction which causes into-turn bank, i.e. it tries to restore a balanced turn. If the turn is a slipping turn, again centrifugal force will move the pendulum in the sense that picks the lower wing up, tending to restore balance.


So yes, if the left bank increases the pendulum moves left-er relative to the model's vertical axis which will cause right-bank aileron. I think that if a wing tips it must take a measurable time for a turn to be established. If the ailerons can pick the wing up before this happens then good. The ailerons should be deflecting as the wing is tipping. I'll be aiming to lever them to attain a good deflection even with shallow bank angles, if the layout allows this (it's hard keeping this mechanism out of sight), but the main thing is how quickly they'll act, and that requires a system with negligible friction, which is difficult too. I suppose the way to look at it is that this isn't a system that would allow a not-very stable model to fly in a gale, but which might be made to work so as to increase its margin of safety in lighter airs. Yes, in theory a model like this could complete long circling flights in calm air, but experience with low-wingers with much more dihedral than the Tempest makes me think it's unlikely, and anyway when do we get calm air? Smiley.

Stephen.
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« Reply #20 on: June 04, 2014, 04:59:55 AM »

Lastly the fuselage - the double-curved rear fuselage was made by wetting sheet and binding it to a polystyrene form. You end up with left and right shells which are joined along the centreline, like a plastic construction kit. This gives you a monocoque sleeve which is braced with a few balsa hoops, and which should slide onto the stick-and-former fuselage frame with complete accuracy (!). Should, but something has gone a bit wrong in this case, the accuracy is a bit, er, less than complete. Anyway, that sentence signals that at last I've got this story up to the present moment Smiley Smiley.

The pictures of the engine exhaust collector ring and spinner show that my turning of large items has improved - they're not round, in any sense an engineer would use the word, but they're a good deal rounder than what I've generally turned out hitherto!

The metal band around the rear cowling former is silver mylar. The Tempest II in the RAF museum has this as bright, bare metal, it looks like it might be stainless steel. I imagine this is the firewall, and that this is a genuine representation of the original's colour scheme, so I thought it would be good to try to emulate it. However since then I've learned that the museum's Tempest is a 'late model' whereas the one I've decided to represent is an early one. I can't find a single photo of an early Mk II that has a bare-metal band. . .hmmm, whether I leave this feature, as a bit of bling, or whether I do the authentic thing and spray over it with grey and green, I don't think I'll know till I've got the airbrush in my hand Smiley.

Stephen.
Attached files Thumbnail(s):
Re: Hawker Tempest II, 1/24 scale rubber power.
Re: Hawker Tempest II, 1/24 scale rubber power.
Re: Hawker Tempest II, 1/24 scale rubber power.
Re: Hawker Tempest II, 1/24 scale rubber power.
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Don McLellan
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« Reply #21 on: June 04, 2014, 04:55:28 PM »

Great stuff Stephen.  Always fascinating watching how you do things.  Very interested in the pendulum as well.

Don
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DavidJP
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« Reply #22 on: June 06, 2014, 11:35:24 AM »

I have ben admiring your work generally Steve and noted the intakes.  The ones on my West Wings Sea Fury looked quite nice in the raw state; but then I started to cover the airframe in the wrapping tissue supplied. I should have realised from the outset this was a silly mistake and used Esaki and airbrushed it to suite. But no - obstinate or silly or both.  And the tissue got all inside the intake and it now looks quite a mess because it seems impossible to remove.  So I am going to see how it flys and then decide whether or not to have a general refit. but of course it is intended for "Kit Scale" so intense detail, as you are so admirably portraying, will not be required.

Well done though - masterclass stuff and all that.
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Prosper
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« Reply #23 on: June 07, 2014, 06:48:15 AM »

 Thanks Dave!

. . .and which should slide onto the stick-and-former fuselage frame with complete accuracy (!). Should, but something has gone a bit wrong in this case, the accuracy is a bit, er, less than complete.


Well, I had to scrap the rear fuselage shell. Once it's glued along the seams, then each station has a fixed circumference, and if that doesn't match the circumference of the former it has to be fixed to, then you're scuppered. Try to fix the skin to the former at one point and it bulges out somewhere else. Cut out relief wedges from the skin and when they're closed up they cause kinks and ridges elsewhere. I stripped the whole thing off the frame and moulded two new half-shells, being extra attentive while binding the wet skin to the polystyrene mould. Luckily I had one last sheet of aliphatic coated balsa - I didn't fancy making more at present. It was the lowest-grade sheet in terms of imperfections but it'll have to do. I was extra-extra attentive when cutting the seams of each half-shell, and when gluing the seams up.

This time it worked and I'm in business again. There's a difficulty to overcome now which is that the tail section of course has to match the rear fuselage - the join has to be as near invisible as poss. The tail section was made as a matched pair with the now discarded rear fuse. shell. Getting the new one to match exactly will be no stroll. I made a big mess of this with my Fw 190 model and have kept telling myself how I'd get it just right this time. . .hmmmm. . .

I've also fixed the belly panel, which has distorted the thin, poorly-supported wing skin it joins to. Never mind, live and learn, live and learn. . .

Also made a spinner cap. I made a balsa plug to blend with the spinner and used this to plunge-mould a cap from 40 thou plastic card. Since the plug matched the spinner exactly, this meant that the cap was ~ 40 thou too big all round, but when I reduced the length and gave it a sanding, it fitted well. The Tempest's spinner is absolutely enormulous. Just the plastic cap on this model weighs 0.5g. Probably need weight there, but still makes me cringe a bit. The weight is starting to ratchet up fast.

Pic 3 shows using a brass rod as a guide for cutting the seam of a fuselage shell, still attached to the polystyrene mould. The rod conforms to the curve of the mould. The cut is visible just above the top of the rod.

Stephen.
Attached files Thumbnail(s):
Re: Hawker Tempest II, 1/24 scale rubber power.
Re: Hawker Tempest II, 1/24 scale rubber power.
Re: Hawker Tempest II, 1/24 scale rubber power.
Re: Hawker Tempest II, 1/24 scale rubber power.
Re: Hawker Tempest II, 1/24 scale rubber power.
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sparkle
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« Reply #24 on: June 07, 2014, 06:54:05 PM »

 Grin Amazing work!   Cool
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