Today I added Corgi AA35411 the 16(R) Squadron Jaguar. A good tooling with a couple of clunky bits and gappy joins and, of course, the signature mini-pilot!

One of the air-brakes fell off (it wasn’t stuck down) – I didn’t realise this was a separate bit. The other one came off quite easily too, so now I can display the model with the them deployed quite easily! I seems strange that these are a separate unit, however, I suspect that the a/b’s deployed feature was a planned option that got the chop somewhere along the line!

Added HM7601 the 541 Squadron Supermarine Spitfire PR.Mk.XIX today. Overall a good model but it’s a bit of a compromise – see the comments below.

Modelling the PR.XIX must have presented a bit of problem to HM, hence the compromises. There were two versions: early production, and late production with subtle but important differences.  HA7601 should represent an early production model, and HA7602 a late one. Let’s look at this HA7601 and pick out the differences between the two. The most important difference was that early versions were not pressurised. RM643 was one of these. Starting with the wing, the early production models (RM626-642) were XIV’s with the PR.XI ‘bowser’ wing (armament removed, extra fuel tanks, fuel pump bulge etc.) and a modified cockpit. These wings had the short ailerons just like the ones featured on the model.  The later versions had full span ailerons i.e. up to the wing tip. So the wings are, I believe, correct for RM643. This means that if HA7602, the Swedish S.31 is to be correct it should have full-span ailerons, rather than the short ones seen on HA7601.

Now to the Griffon nose. HA7601 features the ‘blower’ for the cabin pressurisation. This is the elongated fairing below the exhaust stacks. As RM643 was unpressurised it didn’t have this feature.  HA7502 should feature this as it was pressurised, but it should also have the small exhaust fairing just behind the cockpit (note, however, on BBMF PM631 this has been deleted!). Now to the cockpit. HA7601 shows correctly the hinged cockpit door. HA7601 shouldn’t have one, it was sealed, and should have the covered canopy slide strakes and other pressurisation equipment. Wheel hubs on RM643 were 4 spoked, whereas the later S-31 had three spoked hubs. 

 Now back to the QC issues I was discussing a couple of posts back. I’ll stick with HA7601 because it demonstrates some of the problems I mentioned.

Here we see ’show-through’ of  dark paint through a light one. Unfortunate in this case because the invasion stripes were painted around the roundels on the real thing (and hastily!). We also see serious problems with ink  take-up in the panel lines.  Either there wasn’t enough ink taken up on the tampo pads, or the viscosity was wrong so it didn’t flow into the panel lines. The sequence on decorating is easy to deduce in this case. First the blue, probably electrostatically applied, followed by the hand sprayed and masked white stripes (hence the slight overspray). Then came the tampo printed black, followed by the tampo printed blue and red roundel.

I haven’t seen a production example of HA7602 yet btw.

Today I added Corgi AA38402 the Bristol Blenheim Mk.IF Nightfighter. A first glance a good model but unfortunately the tooling errors and ommissions  seen on the first one have been carried forward. Just looked at AA38404 and it’s the same; so it’s unlikely the tooling will be changed.  OK it’s sort of accurate but it’s an attention to detail and the QC issue again. Makes you think again about pre-ordering – I did for these. But, on balance, in the future I think I’ll take the risk and wait to see the production model before buying (especially for a new tooling).

Added Hobby Master HA7502 the CAF “Peashooter”. Like the last one an excellent little model with the few flaws being highlighted by the plain camouflage. 

Curses! Hadn’t noticed that Corgi have mispelled Tempelhof on that Ju-52  – it’s barely noticeable though.

…added the Corgi Ju-52 AA36905 in Lufthansa livery. First impressions is that this is a very nice model, if you ignore the small but significant errors.  It looks good with a very light silver finish -  looks like a natural metal finish but it is sprayed. Tampo printing is good too, considering the corrugated surfaces, but slightly misplaced. The model is based on D-CDLH and, as there are literally thousands of reference pictures, it should be perfect. Obvious and forgivable ommisions are the lumps and bumps required for modern-day flying. Otherwise, it has the wrong pitots – it should have two, one on each wing. The cockpit canopy has too many bars, and there is no centre-line engine covering plate on the real thing (stops engine oil etc. streaming up to windscreen).

Now to continue with the potential problems of model production. After the casting has left the mould it has excess metal on it associated with the process. These can be removed in several ways mainly by hand but some excess may be tumbled off on smaller parts. They are literally put in a big rotating drum and the excess is broken off by impact! Most parts will then be polished by tumbling  in another drum filled with, typically, small smooth pebbles.  I have no idea whether these damage the detail in any way? I forgot to mention that to aid the removal of the casting from the mould, a special lubricant is sprayed onto it. Usually this is a water-based emulsion and, surprisingly, does not have any impact on the way the paint adheres to the cast surface. Painting is obviously the next stage. If  it’s a single colour over a large area then the paint will be applied electrostatically.  We rarely see any problems here, most are caught at an early QC stage, althoughI have seen examples of underspraying. The big problems occur in the subsequent painting processes. These may be function of the materials the model is made out of, or a function of faulty processes. The first is to do with the recent trend in the increased use of plastic. It’s the mismatch of  shade, opacity and texture caused by the different way the paint is taken up on metal and plastic that is the issue. Usually it’s a feature of a specific model/livery and unique to the whole run, and there’s nothing we can do about it (except moan  in the hope that more care is taken in the future).  The two main processes that can be faulty are the spraying of detail, such as camouflage, and the tampo-printing of detail such as nose-art, logos etc.  With spraying the most common problem will be the mis-alignment of the detail mask – this causes that annoying overspray we see so much on camouflage. With tampo printing the problems are usually associated with a: operator error causing misalignment of detail (roundels typically), or b: poor QC of the paint causing too thin a paint layer (show-through of underlying paint) or failure of take-up in recesses such as panel lines. Annoyingly, because the model is made up of several parts the problem may be limited to only one of them e.g. the wings may be perfect but the fuselage has overspray. This is because each part is usually processed in a different batch, possibly days apart. Other things to look out for will be smudges, fingerprints etc.  

Here’s a couple of pictures of a batch Corgi AA36204 being tampo-printed!

    

A collector has asked me if anyone has some Corgi History Channel models they want to part with. They are: HC 31109, 31918, 32223, 35210 & 35808. These came to light in the recent Collectors’ Club listing. I’ll update the relevant pages when I get time. Explains a few ‘missing’ models. Basically, these are Legends releases in History Channel packaging.

Added HA1210 the FAA Avenger II today. 

Apparantly the Fleet Air Arm didn’t really use the torpedo capability of the Avenger that much, but I thought I’d do this picture anyway.

Continuing with the Corgi XIV Spitfire I’ve done a diagram to show where I think the problem is. I’ve overlain the Corgi model wing over the plan view of the wing (shaded red). I’ve used two reference points: the rear of the canopy (which should be in line with the edge of the wing before the fillet) and the rear of the Griffon bulge.  You can see that the wing is  is oversized. It’s not an exact representation but it gives you an idea where the problem is.

Now to the QC issues again. I’m returning to the ‘zinc pest’ problem again, because I’ve since discovered that the amount of contamination in the white metal needed to cause a problem can be extremely small. Even more worrying is that, due to the recent spiralling costs of raw materials, there is greater use of recycled material. It’s worrying because this brings with it a greater risk of contamination.  A certain percentage of the diecast metal has always been recycled in the factory. When a cast is removed from the die there will be some excess metal that has to be removed. This cannot be wasted, so it is recyled. I am assuming that the same goes for material rejected further down the production process e.g. after painting. Both will increase the risk of contamination. It’s likely that different parts of the model will be cast at different times and ,therefore, from different batches of metal. This could mean that ‘zinc-pest’ could affect one part of a model but not another i.e. one part comes from a contaminated batch of metal, whereas the other part doesn’t.

Added the first of the Corgi Mk.XIV Spitfires today. Apologies, but a computer problem delayed the update.

This is the first ‘official’ CAD produced diecast aeroplane from them ( I have long believed that the 1:32 Hurricane was an early venture into CAD). In the past a prototype was modelled by hand and this is translated into a tooling though a complicated series of  mainly manual processes. With CAD the model design, tooling design and tooling fabrication processes can be done on a computer. This should lead to more accurate models, however…

…with this model I’m slightly disappointed – it just doesn’t look quite right. The model appears pretty much dimensionally correct. I’ve done a quick check with a caliper against the plans in the SAMS Modellers profile and, at first,  it looks OK.  The cockpit canopy is, believe it or not, correct. Some claim  bulge is slightly too small, but I think the problem is caused by the thickness of the transparent plastic. It acts like a lens and draws you eyes to the inner surface of the moulding, making the bulge look smaller. The thickish painted frame lines add to the problem. Unforgiveable though,  is the missing round rear-view mirror. Most of the fuselage dimensions appear OK too. Maybe the Griffon bulge needs more definition and ‘plumping up’.  The spinner is a problem too; it’s measures OK, but the problem lies with the division between the front and rear parts – it’s too far forward by the thickness of the spinner plate. Also, the blades are also a little too far forward. This makes the spinner look ’stumpy’. So the fuselage and tail are OK, but I just felt there was something wrong (I am assuming here that the plans in the SAMS guide are correct). I noticed that, on the plans, the rear part of the canopy is in line with the trailing edge of the wing (before the fillet). Look at the model and you will see that the trailing edge is some 2mm further back. A quick check of the nose to canopy to tail dimensions showed they were OK. So this means the wings are wrong!!!  Wingspan first: Plan 152mm, Model 156mm, thats 4mm too much. Same for the chord, it’s all about 2mm too much. At this scale that’s a big error. That, I think, is why the model doesn’t look quite right? I’m sure I’ve got this right, but a second opinion would be appreciated. I’ll do some more thorough checking too.

 Other issues are with the paint matching between the green painted sections of the plastic canopy and the metal fuselage (a common problem).  Port ID light on underside of wing is pierced by the pitot, but the light probably shouldn’t be there. Slight overspray too with the black of the D-Day stripes where the mask hasn’t been located properly. Usual problems with paint take-up in the fairly thin but prominent panel lines. Yellow leading edge paint is very thin so black of the stripes shows through. Also check that there is no damage to this paintwork from packaging (saw this on a model on display in a local shop). It has the Corgi Spitfire ‘look’ so sits happily next to the Merlin Spitfires.

Corgi have changed the format of the l/e cards with recent releases. These are almost the same size as the HM ones.

As usual references and picture can be found in the Osprey No 91 ‘Nigeria’ Sqn By Peter Hall  and Griffon Spitfire Aces By Andrew Thomas, Chris Davey. Btw, I was intrigued by the nose-art on the model. It shows a lady astride a V1 -  and she looks like she is suffering from serious motion sickness. It’s not, however, projectile vomiting – it’s just the interpretation of the name ‘Brunhilde’ that is part of the nose-art on the real thing!  See the photographs in Osprey ‘Nigeria’.

No time for the more quality stuff today – sorry.

Added the Hobby Master Beaufighter VIF HA2304. This is the one in the SEAC colours. Apart from the issues discussed previously, there’s not alot wrong with this model – very pleasing. Note the nicely done control surfaces (fabric covered on the real thing) . There’s a photograph and a profile in the Osprey Beaufighter Aces of World War 2 by Andrew Thomas.

Now back to the potential for problems with models. If we are honest, most manufacturers will have little interest in what happens to a model once it has been sold. Up to that point the aim will be to produce a model that looks and feels ‘fresh’ and will stay so during transit. They have learned over the years to eliminate the problems caused by the  shipping and storage (returns cost them money). Corgi is an experts at this, Hobby Master is catching up. So do they take special care in the manufacturing process to ensure that the model will last some years? 

The first stage of the process is of course the diecasting. The bulk of the model will be metal, specifically Zamak (zinc alluminium magnesium and copper alloy) or ’white metal’ also known as ZnDC (zinc for die-cast). There are lots of different forms of the alloy (see Wikipedia). Up to the 60’s this type of alloy was sometimes prone to contamination with lead and other metals. There was little quality control in the process because the lifetime of the model (toy) was not supposed to be very long. You were supposed to play with it (and eventually destroy it with your air-gun at the end of the garden). The most common problem is the so called ‘zinc-pest’. This is essentially a corrosion of the crystalline structure of the casting – it literally crumbles away, and is irreversible. More recently quality control has improved significantly so the problem is less common. I have not seen it on any of my diecast aircraft models – yet. Recently I looked at some of my older Corgi AA models in the loft and couldn’t find any trace of the problem (I did, worryingly, find something else, but I’ll come on to that in another post. However, if you are buying older models from you should check for this problem. Poor storage in a warm  high humidity environment will start it off.

Other problems with the diecasting process will be stress cracking, distortion and porosity caused by the way the molten metal flows in the tooling and how it cools down. Most of these problems are (should be) spotted during an early QC stage i.e. just after the cast has left the mould and during the assembly process.  Again, if you’ve purchased a model its worth checking to see if these problems exist. Distortion will be the main problem – I’ve seen a few examples of this with smaller components such as the undercarraige on the Corgi AA Liberator.

More next post….

Added Corgi AA38202 the 1:72 BEA DC-3. There’s a review of it below. In view of the fact that this is a new tooling I was expecting a nice surprise – I got the surprise, but not the one I wanted . The review is below.

 

I was a little worried about this model when I saw the engineering prototype and was surprised by the amount of plastic used – it makes for a lightweight model. Is this inevitable with the rising costs of raw materials? The grey, clear and black are plastic. The orange and silver (undercarraige) is metal.

 

The tail is plastic (more on that later), as are the lower parts of the front and rear fuselage, the nose, the complete engine assemblies, the underneath wing panels, and the inserts in the fuselage for the various window options.  Because the upper part of the fuselage is one piece there must be at least two toolings for the passenger door and cargo options. The packaging is of the usual solid Corgi high quality and, as usual, features a photograph of an early pre-pro model.  In  fact the packaging weighs more than the model and stand together!

The model I chose to get was the BEA one. Once out the box the first impression is that model looks OK, it’s the right shape, but your eyes are immediatley drawn to
the very prominent panel lines which give the model a crude toy-like appearance – the silver paint does accentuate this. They are quite heavy, especially on the wings,  considering this is a recent tooling.

The vertical stabiliser is a bit of a shocker, it’s nothing more than an unprofiled slab of plastic with scored detail to represent the rudder. The plastic is impossibly thin at about 3mm at the base to 0.89 at the top, and can be flexed. It is horrible.  The horizontal stabiliser is a bit better with some thickness, but the detail is again scored lines with some minor raised detail representing fabric-covered ribs and trim-tab linkages. Given that the tail surfaces are plastic I cannot see why the rudder and elevators were not moulded separately to give the tail the proper DC-3 look.  The fabric surfaces should also have been given a slightly different texture to distinguish them from the metal. 

The tail-wheel is fixed and a fairly simple affair; this is 1:72 so why doesn’t it caster? Moving to the doors, again scored, with simple raised hinge/handle detail detail. An opening door with steps could have been easily accommodated as optional inserts. This could have been very effective with cargo door option. As mentioned the window options are detailed using a plastic insert, however this leads to a slight, but noticeable, colour and texture difference with the silver paint. The wings show very heavy panel lines, and again the aileron and flap detail are scored outlines. The ailerons, like the rudder, have simple raised line detail. The engines are all plastic and again very simple. There’s a hint of the cowl flaps’with more scored detail. Again this distinctive feature could have modelled as an option as the engine cowling is made out of three separate plastis parts. Engine intakes and exhausts are also relatively simple affairs. The exhaust stub is solid with a blanked end!  The down undercarraige option is metal with rubber tyres; the up option is all plastic. Both are over-simplified, especially the up option, with no internal cowling detail, just a flat blanking plate.
Now to the nose, it’s all wrong, especially the cockpit windows and the pitot tubes. This aircraft never had the newer single front window – it should be in two parts. The pitot tubes are the wrong type. On this a/c they were a single unit of two tubes (Pilot and F/O’s). I cannot recall ever seeing this two-tube configuration (please correct me if I’m wrong), however, it appears on all the releases so far – is this an ‘engineering’ misinterpretation? The pre-pro’s were OK in this respect, btw. Paint, colour and detailed tampo-printing is OK, and, because the panel lines are so thick, there are none of the classic tampo-print paint take-up problems.

In summary, this is a very disappointing tooling. It is over-simplified, inaccurate and expensive.  

The real a/c started life as a C-47A-DK and served in the USAF as 42-92155. It was transferred to the RAF as a Dakota C.3 with serial FL563. BOAC the got it as G-AHCZ. Next it went to Iraqi AW as YI-HCZ, then to BEA as G-AHCZ again. Cambrian then took it over eventually selling it to World Inter Supply Services as 5B-CBC who leased it to Cyprus Airways. It ended life scrapped at Bierut!

Now to continue with the issues with conservation of diecast models. Firstly, I forgot to mention the expanded polystyrene foam used in the packaging of some larger models. It’s a very stable substance and, of course, very good at protecting and insulating the model. There may be an issue with residual chemicals left over from the manufacturing process (benzene). There’s an obvious fire-hazard to consider, and there are concerns with styrene migration in food containers (so don’t eat the packaging), and with gases released with abrasion of the foam (don’t shake the box).  If styrene does leach out of the packaging then, as it is volatile,  could it accumulate in the box until you open it? I can’t find any reference of the foam damaging the product contained in it. I suppose very shiny paint could be abraded but that’s easily solved by putting a layer of tissue between the foam and the model. For the longer term there is nothing conclusive to say, other that studies are underway as to the suitability of  polystyrene foam as a conservation material in museums!

Next post I’ll look at the manufacturing process and identify where problems can occur.

Another excellent model from SkyMax despite the problems highlighted previously.  It’s argued that this livery is a compilation of several!

I’ll continue with the ’conservation’ thread with the next post, including comments on the expanded poly foam seen on the larger Corgi AA models. I’m also digging around some of the older models in the loft for traces of deterioration and other problems.

Also had to have a little lie-down today after the shock of seeing the new Corgi DC-3 (BEA one). It will be the subject of the next update.  Do I like it or d0 I hate it?