Vulcanicity's Stranraer and Heyford dual mega build!

[CedB]

More great scratching Phil - good job!  

[Terry1954]

I'm perplexed to understand how I ever missed this superb dual build of two superb aircraft.

 

Brilliant work so far, I'm in now!

 

Terry

[TheBaron]

Handsome research and building Phil.

[Vulcanicity]

Hi biplane followers!

Another long gap I’m afraid, but this time, finally, my PhD thesis is Ready For Inspection (by my examiners)! That means more modelling time – and about time, if you ask me!

At the end of the last post, I left you with a largely completed Stranraer hull and tail, complete Heyford fuselage with the fabric effect sealed with primer, and completed Stranraer wing sections including the landing light ready for primer. I’ve also assembled the Heyford upper wing.

 

This only leaves the Heyford’s bottom wing. As I mentioned before, this is complicated by the fact there’s a bomb bay buried within the wing in the thickened centre-section. This was a major part of the reason the Heyford is so oddly-configured: the bomb bay was designed to be close to the ground to simplify and speed up loading it using the relatively primitive 1930’s equipment and provide a wide, clear space clear of excess structure – hence the attachment of the fuselage to the upper wing. For this reason (and not its sparkling high-speed performance) the Heyford was marketed as the “express bomber” by HP!

 

 In the real thing, this bay was subdivided into ten internal compartments, and combined with the four wing bomb racks and two Small Bomb Carriers, the thing could accommodate an impressive variety of munitions, as suggested by this diagram from the Heyford III AP:

 

 

Typical bomb loadouts actually carried included 16x 112lb; or 12x 120lb; or 10x 250lb; or 4x 500lb and 8x 20lb, or 4x 20lb and 4 flares.

 

Matchbox provide either an insert for closed bomb bay doors with odd raised ribs, or this insert, which is supposed to represent the compartment sides and roof of the bay, and opened doors in pairs:

 

 

Problem is, the Heyford was a large, fabric-covered biplane, and all that there was between each compartment was a rib structure, like this:

 

 

So having ground off the locating tabs for the insert, I set about making these ribs in situ using plasticard. Mindful of the need to try and cover as much space with bombs as possible, and desperate to try and replace the dismal kit offerings, I went for the 10X250lb loadout, and duly bought these beautiful things from CMK:

 

 

I got off to a shaky start (notice the, erm, variable spacing here on the bomb bay roof!)….

 

 

But I eventually got there after hours of head-scratching, building up from these top webs attached to the bomb bay roof part:

 

 

You might wonder why I’ve only completed the central four bays. Well, there’s a tale to be told here! Somewhere shortly after the first picture, I thought I’d better check the bays were wide enough for my lovely resin bombs. The width was no problem, but the length…

 

 

That’s right: compare the photo with the Heyford loadout diagram above, and you’ll see that there’s something almighty fishy going on with these “250-pounders"! I checked and double checked the dimensions of the bomb bay against all the plans I had, including from the AP, and the bombs are definitely wrong, not the bay. Someone at CMK got their dimensions in a twist, as these resin parts actually scale out perfectly for the 500lb GP bomb. The upside is that, switching to the 500lb/20lb/flares loadout, I can get away with only building the centre four bomb compartments and leave the outer six closed, so this has actually worked out very well! But if you're thinking of buying these bombs for something which 100% definitely needs 250-pounders:  You have been warned!

 

Anyway, with my thesis slain, I’ve at last been able to crack on and finish this section, which after a vast amount of fettling goes together thusly:

 

Next stop primer, and closing up the last wing section!

 

One other job I’ve tackled is scribing the Stranraer’s nacelles, having assembled the two halves. This has been a struggle, as there are all sorts of compound curves, and it’s not certain from photos of 920 what some of the lines do directly underneath the cowlings.

 

 

The Stranraer’s oil coolers were housed under neat double-ended scoops on the outboard sides of the cowlings, and, as far as I can tell, partly faired-in for streamlining. It’s easy to joke about the performance of these lumbering old aircraft, but the more I research the Stranraer the more I’m impressed by Mitchell’s determination to wring the last ounces of performance from the biplane flying boat idea.

 

These scoops were much larger on the postwar Wright Cyclone-modified Canadian aircraft such as 920 – but this is one modified feature Matchbox seem to have got right and ignored. All I had to do was some thinning out, add the core from some plasticard rod and PE mesh, and cut a suitable square slot to fair it into the cowlings, and Bob’s your uncle.

 

 

 

 

That’s all – hopefully not another six weeks before the next post this time!

[bbudde]

That's great for the old Matchbox one. Great stuff!! Go on further with that!

[bigbadbadge]

Good to see you back on these beauties Great work on both loving that bomb bay.  

Keep up the good work. 

All the best 

Chris 

[woody37]

Great progress on these old beauties

 

[TallBlondJohn]

1 hour ago, Vulcanicity said:

Someone at CMK got their dimensions in a twist, as these resin parts actually scale out perfectly for the 500lb GP bomb.

 

Perhaps it was a product mix, and CMK put 500 pounders in the wrong pack? Might be worth letting them know.

[Vulcanicity]

Hi all!
Only five weeks between posts this time...I'm getting better!

Having at last completed the scratchbuilding inside the Heyford's bomb bay, it was time to break out the paint, for the first time in what seemed like ages. Of course, I've got no idea what colour this all was and any guess of mine is probably wrong, but having gone with interior green and natural dope on the inside of the fabric-covered fuselage sections, I might as well at least be consistently wrong!

 

 

With this done it was time to finally button up the last major wing section of this dual build two-year endurance test.

Considering all those ribs were largely built by guesswork, the degree to which they joined with the wing lower surface at the edges was deeply pleasing! A couple of gaps along the centreline here, but these are easily dealt with.

You can see that I've covered over the outer bomb bay sections here; this is simply the closed bomb bay insert provided by Matchbox, with the middle section cut out and the odd raised ribs ground off and replaced by scribed lines.

 

 

The next big task has been engines - you saw my starting efforts with the Stranraer nacelles last time. MB provide some quite nice engine parts for the Heyford, but half the lines are raised and the other half etched in typical MB style (see also: Halifax I/II). Here's a before-and-after: I scribed all the raised lines and strengthened several etched ones which had worn on the mould over time. The little scoops are also better replaced with plasticard replacements, and there are some odd vents in a row which I added.  These can't be anything to do with engine cooling, as they're behind the firewall in the real aircraft (the angled panel line just ahead of them here). There are also three not four - an error I later corrected along with tidying them up better than you see here.

 

Lastly, you'll notice I opened up a section behind the exhausts - this is a prominently open hole on the real thing. More on this anon...

 

 

MB interpreted the bizarre forward-angled exhausts on the Heyford as kinked, round-section pipes with a flat round face at the front - presumably representing a simple forward-venting pipe. However even in the 1930s, a respectable aircraft designer wouldn't have blown hot air forwards on an aircraft flying forwards, surely?

 

Well, no. A closer inspection of the pipes on photos suggests they're a strange, smoothly tapered shape like a sort of flattened gearstick, with  the exhausts venting downwards and backwards through an angled slot. Apparently these stubs incorporated a complex U-bend which suppressed exhaust flames. Now you know! Here's a zoomed-in shot of the real deal, and a comparison showing my attempts to whittle this feature out of MB's parts. Just as well I used to be in the Scouts.

 

 

Under the engine is a hefty ribbed tunnel which incorporates the radiator. Ten out of ten for effort - MB provide both the flat-faced radiator fronts of the Heyford I and II, and the wedge fronted design introduced on the Heyford III, which you can just glimpse under the engine in the period shot above. However, the rear face of the radiator is just blanked off, while my refs appear to show a hollow duct extending well forward of the v-shaped interplane struts, with the rear face of the rad proper being forward of the firewall, and the steel tube cores of the struts protruding through the duct in the middle. Not following me? Well this is what I'm getting at:

 

 

Not the neatest bit of scratchbuilding, but the duct itself was very hard to clean up, and this area will be very obscured on the real thing. The ribbed bit of plastic representing the back of the radiator core was made by 1.) scribing lots of parallel lines on a plasticard sheet, and 2.) stupidly forgetting I had lots of bits of CD case left over from the flooring in the cockpit!

 

You'll remember I was waffling on about the gap behind the exhausts. None of the period shots I can find show any daylight through this, so there was clearly a chunk of Kestrel blocking the gap, however two sections of the engine bearer are invariably visible just inside. So I blanked off the holes I'd cut with black-painted plasticard, and used two bits of 0.8mm rod to replicate the bearers. You can also see the exhausts installed, the third of four little vents installed (more cleaning up of the other three to do!), and one of two random large holes which seem to be in the radiator duct. I have no idea what these were for - they are clearly see-through in photos and not backed by a duct or vent or anything. Clearly a go-faster lightening feature!

 

 

Another sub assembly I've been working on is the Heyford's wheel spats. I may be 28 but I'm really a child inside, and can rarely resist movable wheels (or gun turrets!). One of these spats was easily assembled with the wheel free-spinning but the other was a really tight fit and needed a fair amount of material grinding off the insides of the spat parts at the front, to allow free spinning. Once achieved, these were easily painted and ready for assembly.

 

 

And now finally, a shift in shades of green. With all this Heyford hammering, the Stranraer has taken a bit of a back seat, but I've carried on tinkering with the engines. Those with extremely long memories might remember I've (shock, horror!) bought some AFTERMARKET GOODIES to go here. You can see why - the kit Pegasus are something of an embarrassment to the quality of the rest. For any who own the MB Swordfish you'll know this is far fro the best MB could do at the time. I opted for CMK resin replacements, as shown here. I had to replace the resin pushrods though, as they were all too short!

 

 

If it wasn't for my July 1979 copy of Scale Models and it's review of the (NEW! EXCITING! GROOVY!) Stranraer kit, I think I would have left the Stranraer's cowlings as they were in the kit and yet somehow always be slightly uncomfortable about how they looked. However the review obsesses somewhat about how wrong they are in profile, and insists that the modeller should replicate a cutout on the  the rear edge which reduces the cowling's chord on the top side. The latter feature I'm sure is bogus - at most I can only find it apparently visible on images of the prototype K3973. However the article is correct in saying that the cowlings should be more curved in profile and need thinning down at the rear edge rounding out at the front, and the diameter of the frontal aperture increasing. You can see the difference here, with an unmodified cowling on the left. Test fitting the engine-cowling-prop assembly I'm actually amazed how much difference this makes. The kit cowlings as supplied are closer to the Wright Cyclone installation on the postwar Canadian civil aircraft - perhaps another consequence of the MB research trip to Hendon!

 

 

Well that's pretty much it for now! This build is rumbling on towards the 18-month mark but finally, finally, things are beginning to come together. See you again!

 

Edited October 23, 2018 by Vulcanicity

[Tweener]

Having wanted to do a Stranraer ever since I saw one, I can tell you one thing for sure, I will be coming back to this when the day comes that I get down to giving one a go. Hopefully that comes sooner than later. These corrugated Russians are all starting to look the same... 😮

 

 

[bigbadbadge]

Very nice work indeed.  I look forward to your next instalment.   

Cracking work. 

All the best 

Chris 

[MarkSH]

Absolutely cracking work, really enjoying watching this. I have the Matchbox kit and also the Revell boxing. however an interesting problem I have is that the Matchbox kit has a duplicated sprue in it with all the upper wing parts but does not have the sprue with all the lower wing parts! I still thinking around that one. Keep up the fantastic work, very inspirational.

[CedB]

Lovely work Phil, expert detailing as usual  

[Martian]

Super work! Better the bombs are wrong than all that lovely work you did on those wing ribs.

 

Martian 👽

[Vulcanicity]

Thanks all! MarkSH - send it back to Matchbox at the original postal address. What could possibly go wrong?!

In all seriousness, yeah that's awkward having duplicated top wing halves - I feel like that might have to be a far out what-if (1930's RAF Ekranoplan anyone?) Or: a recovery diorama, on a Queen Mary trailer?

(Image credit from http://www.theinvergordonarchive.org/picture/number1404.asp)

 

I'll pick up where I left off last time. One feature of the Heyford's engines conspicuously missing from the kit (and one of the two sets of plans I've got) are the oil coolers. In all but the very early aircraft these were low down on the starboard side of each nacelle, pretty much directly under the exhausts. They're a type that seems to be standard on RAF types of the period, with examples on Bulldogs and Hart derivatives, among others: a series of lozenge-shaped vanes joining two round pipes. I simulated the coolers from plasticard, sandwiching rectangular and pairs of tiny circular pieces, letting the whole lot dry then sanding the corners off to make the lozenge shapes:

 

 

 

These nacelles have been like mini kits in themselves! The last job was to add the radiator fronts (see the shot above) and several tiny scoops and bits of piping (below)

 

 

Next job on the Heyford was finishing off the spats. Having ensured the wheels go round (the wheels on the Heyford, as is well known, go round and round; round and round), I scribed in the removable panels which exposed the wheel, and added a little cutout and some of the structure visible behind. The door with the bulge covers some of the engine starting and priming gear.

 

 

With this done, I've attached the spats and engines to the wings!

 

 

After much squinting at gloomy photos (why didn't someone paint a Heyford white, and take good pictures of it, damnit?!) I ascertained the ribbed surface on the sides of the monocoque forward fuselage continues underneath. MB couldn't really represent this without slide moulding (too groovy even for the mid-70s) or two extra pieces, so I'll let 'em off. Out with the plasticard!

 

 

While I was here, I sanded off the misplaced (and mis-shaped) crew door, and scribed a new one. The shape is an educated guess from the fuselage framework schematic in the AP, and one very bad photo.

 

 

Lastly, a few outstanding details on the tail. I cut out the tops of the fins and added some scratchbuilt rudder balances:

 

 

Finally, I cut the tiny triangular access panels seen on the rear fuselage sides from my trusty San Pellegrino foil, and (with much Grade A cursing) added some control runs from my drilled out conical fairing just forward of the tailplane. MB moulded the raised fairing on both sides, which needless to say I slavishly copied - but there's only one fairing and one set of cables, on the port side. Doh! Out with the filler!

 

 

That's it for now. Next time...rigging points, and dare I say it...wing-fuselage joints!

Edited November 17, 2018 by Vulcanicity

[bigbadbadge]

Great stuff.  The extra detailing looks absolutely fantastic. 

All the best 

Chris 

[CedB]

More great work Phil  

[dogsbody]

Great job you're doing there. I do have a question regarding the oil coolers. As you've stated, good pictures are hard to find. I have found two, but they both have the other style of radiator than the one you have used.

 

http://aircrewremembered.com/smith-harry.html

 

https://www.imuseum.im/search/collections/archive/mnh-museum-123094.html

 

 

 

Chris

[pheonix]

This is coming on a treat. Looking forward to more updates.

 

P

[bbudde]

As above all. Great work on that. Cheers

[mackem01]

This is a fantastic watch, especially the Heyford. I do love an oddball, particularly one as good as this. MORE PLEASE!

[Col.]

Nice work so far and now required reading from the very start for me. With both kits in the stash I've a feeling your work is going to serve as great inspiration!

[Massimo]

I've just seen thisupdate. You're doing afantastic detailing work on both and the result is outstanding!!!

Bravo!!!

[Vulcanicity]

On 11/18/2018 at 12:20 AM, dogsbody said:

Great job you're doing there. I do have a question regarding the oil coolers. As you've stated, good pictures are hard to find. I have found two, but they both have the other style of radiator than the one you have used.

 

http://aircrewremembered.com/smith-harry.html

 

https://www.imuseum.im/search/collections/archive/mnh-museum-123094.html

 

 

 

Chris

 Thanks everyone! Another long gap I'm afraid - However I am now officially Dr. Vulcanicity! Available for all your tropical forest rodent needs...

 

Dogsbody: I'll try and answer as succinctly as possible. The radiator fronts varied between marks of Heyford, and along with the nose windows in the bomb aimer's compartment, these are the major external recognition feature separating the marks. The Heyford I/IA and II had a flat front to the radiator grille, which was recessed into the semicircular duct. The front lip of this duct was slightly angled upwards in profile - this is the radiator I've used for my Mk. II Heyford, and equates to Part 6 in the kit. Since the Heyford II introduced slightly narrower engine cowlings with a different thrust line, I assume there were minor differences between the 1/1A and II installations, but photos are too few, and the change too subtle to really ascertain this. The definitive Heyford III introduced the other style of radiator, which has the "V" or wedge-shaped front grille seen in your linked photos (Part 7). This mark had a modified cooling system using steam condensers in the wings, so I assume the change in design of the radiator related to this. (The prototype HP.38 J9130 had a totally different radiator design, along with many other detail differences in the engine area).

 

The oil coolers appear to be the same standard design on all marks  - as I said in my last post they're similar to those on the Bulldog and some Hart variants. However on very early Heyford I machines they were carried high up and far back on the starboard sides of the nacelles, under the wing and behind the exhausts/firewall. This is where the main oil tank is housed inside the nacelle. They seem to have been moved much lower down and further forward (to the position seen in your photos) very early on. Very early Heyford Is  had a single long exhaust pipe venting even further back, and my guess is that when this was modified to the three-stub "horned" arrangement, the cooling effect of the airstream was much diminished due to the hot exhaust gases passing right over the cooler, and it had to be moved out of the exhaust stream, at the cost of some longer piping to and from the oil tank.

 

I'm thinking I might do a reference thread for these two types when the builds are eventually finished, and I'll try and collate all this information!

 

Anyway, onto progress.

I've been giving quite a lot of thought to how the rigging and struts are going to work. Most of my previous biplanes have been small aircraft with single-piece wings, and I've just drilled 0.3mm holes straight through and threaded fine fishing wire through them. But with these large aircraft, the wings are all composed of an upper and lower piece, and threading the wire through with a void in the middle is a recipe for hear-tearing and cardiac arrest.

 

So I elected to try using turnbuckles at the  rigging points. A back-of-the envelope count suggested I need upward of 150 for the two aircraft, which was could get expensive if I bought them - cheaper to make them! I made a sort of jig by simply clamping a thickish (c.0.7mm) length of wire horizontally, and then twisted short "U"-shaped lengths of very fine wire (from multistranded electrical cable) around the fixed cable. With a few firm twists using a pair of pliers,  these close into little eyelets with a long twisted stalk, which can then be trimmed down to length, and the finished turnbuckle slid off the jig wire and safely into a ziploc bag. 

 

Here's the setup ready to go, with a line of completed turnbuckles on the wire. It took me ages to find pliers with a smooth, (not ridged) gripping surface - indeed, No.1 bird ringing pliers were the only suitable pair in the house! This is probably the first and last time these two hobbies of mine will intersect! 🦅

 

 

Here's a pair of completed buckles with suitable object for scale:

 

 

And here they are in situ - these are in the lower wing of the Stranraer around the float attachments.

 

 

I'm experimenting in other ways too: frustrated by years of fishing wire pulling through holes under tension, I've decided to try EZ-Line for these builds. The stuff is pretty handy, as I found out by making a test piece with some prototype turnbuckles and a bit of spares box plastic. Unfortunately the only colour I could obtain was blue - so the rigging wires will need colouring silver when done...😞

 

 

Having mostly finished adding the turnbuckles (breaking most of my 0.5mm bits in the process) it was time to progress the builds more visibly by doing the Stranraer's wing-fuselage joints!

 

First, a fiddly job which the lower wings would have impeded. The bulkhead behind the pilot is a very poor fit to the roof of the fuselage, leaving a 1-2mm gap. This might exacerbated by all of that detail I shoehorned in there, but I think the gap would still be noticeable. There's a guide tab on the roof behind the bulkhead (closing off the gap to the rear) so this was a relatively simple matter of rubbing down the paint (not damaging any of the various added details!), filling with plasticard and putty, sanding and repainting. The camera greatly enhances the roughness of my repair - it looks fine to the Mk. 1 eyeball!:

 

 

After that - wings on!

 

 

I then finished the upper centre section by adding the scribed nacelles, complete with oil coolers (seen a couple of posts back) to the wing. This centre section is attached to the fuselage/lower wing sub-assembly by four "cabane" struts, which push through holes in the nacelles. The struts needed scribing themselves (for a fabric-covered biplane there's an awful lot of this!)

 

 

Having added these struts and letting the whole lot dry in situ (dry-fitted to the bottom wings and held in place with rubber bands) I then built up the upper outer wings gradually, one side at a time. I added each upper outer wing, and while the joint was still tacky added the outer interplane struts, again only gluing the upper attachments, and adding more rubber bands to hold the dry-fit. This way the correct dihedral was set:

 

 

Ta-dah!

 

 

Again, the whole upper wing and struts are only dry-fitted to the bottom wing and fuselage, allowing easy painting later on. Getting it all to fit this well was a challenging and stressful operation, made complex by the fact that the aft pair of centre-section "cabane" struts were somewhat too long, causing the rear one of each pair of interplane struts to be dangling in the air - of course this was only apparent once I'd fit all of them on both sides. However, with some fettling and much weapons-grade swearing the whole lot is together! 🤬

 

One last photo for today, in case you thought I was building the Stranraer Mk. IIa (special) glider variant - I've finished the resin Pegasii from CMK, adding cowling braces and pushrods, and they're ready for painting and fitting into the (also complete) cowlings.

 

 

So...only some beaching gear, two floats and a lot of small details on the hull stand between this baby and the primer can!

 

Next time, some rather unorthodox wing assembly on the Heyford...

Edited January 8, 2019 by Vulcanicity

[CedB]

Congratulations Dr Phil!

Nice turnbuckles too - she's coming together now