Wednesday, January 4, 2017

And now for some more completely different stuff

Regular readers (if any) will have noticed that the name of this blog is http://24th-scale.blogspot.com. The fact is that 1/24 (and its close relative, 1/25) is a popular scale for cars, because it is a nice compromise between maximising detail and minimising shelf space. And as a former foreign auto mechanic, good automotive subjects are of interest to me. But nowhere did I claim I would only discuss automotive projects. And I have had plenty to say about resin, so I am not limiting myself to styrene either.



A while back I mentioned the acquisition of the wooden 1949 Chris Craft runabout. I have added to this the recently-released 1959 Century Coronado from Lindberg. The parts bin will come in handy here, both for the Coronado which has a poorly reproduced V8 of some sort, and for the Chris Craft, which has no motor at all. A Thunderbird Tri-Power for the Coronado and a flathead for the Chris Craft are in the wings. Both will need trailers.



I also got my hands on a Zundapp KS 750 motorcycle, modeled in 1/24 by the Japanese company Asuka. Bikes tend to be either 1/12, allowing more detail for the same shelf space as a car at 1/24, or 1/35 for the military modellers who would normally be interested in something like this. The bike was used by the German army in 1941-43, and looks like a vintage BMW with an opposed twin and shaft drive. There appear to be two complete kits in the box, perhaps a mistake; the second complete set of sprues is fully chromed. It also appears that there is a version with a side car, which I would have ordered if I had known it was available.

Moving on from boats and bikes, I got brave and bought the Airfix 1/24 scale model of the De Havilland Mosquito. There aren't a lot of planes modeled in 1/24 because they are so big; the Mosquito in real life has something like a 54 foot wingspan, meaning 26" at scale, so it will need to be hung from the wall or ceiling once complete because none of my display cabinets come close to fitting it. For this reason, model airplane scales typically range from 1/48 all the way to 1/144. The kit is daunting: over 600 pieces, and the ISPM website (click here) flags that it is not for beginners. The instruction manual says it is not suitable for children under the age of 36. Months that is. Right. I'd like to see a 3-year old tackle this.



The Mosquito is of interest to me because it was made largely of plywood, which was considered at the time to be a very advanced composite material. Shortages of metals in the war years made this an interesting option, although the state of the art in phenolic resins at the time made this a very expensive option. The kit also apparently models the two Rolls Royce aero engines well. The RCAF flew these well into the late '50s, so I will look for colours of these later planes. As a side note, the people who worked on this moved on to build the Marcos car in Britain in the '50s, which also featured a plywood chassis.



I will build this at a friend's house because the household includes two young men who are actually pilots, so maybe there will be some advice as to how it is supposed to look. This project looks to be complicated enough that it merits its own blog, and I have created https://24th-scale-air.blogspot.com for this purpose. There is no content there yet, but come back soon!

Finally, heresy of heresies, I ordered a 1/43-scale kit. Yes, this goes against the fundamental mission of this blog, and represents my first foray out of the 1/24-1/25 scale world. But the kit, and the car, is unique.

I have accumulated quite a stash of MFH kits, and have been intrigued by their 1/43 kit of the BRM H16. This 3-litre F1 car, driven by the likes of Jim Clark and Graham Hill, featured a three liter, sixteen cylinder motor consisting of a pair of flat eights stacked one on top of the other and geared together, hence the H16 designation. As the common gear train that connects all the cranks and camshafts is in the middle of the 'block', this is arguably a set of four flat fours of 750 cc each. Intake manifolds were located, pointing outwards horizontally between the inlet and exhaust cams, there were exhaust manifolds both below and above the heads, and I am not sure where they hid the spark plugs.



Probably the only more complex motor out there is the fabled 1.5 litre flat 16 assembled by the guys at Coventry Climax in the last year of the 1.5 litre formula. Imagine 16 moped engines, of just over 90 cc each, allegedly making 180 hp at 12,000 RPM, and imagine all this going to waste a year later with the new 3-litre formula, which they knew was coming. What were they thinking?



Somewhere I recall reading that at a given bore:stroke ratio, the smart money in racing engines is on cylinders of about 375 cc each. This would apparently be a balance between lots of piston area and low piston weight on the one hand, and lots of frictional surface area due to lots of crank pins on the other. I am also guessing that gas flows in inlet and exhaust pipes are getting into pure boundary layer flow regimes as the tubes get smaller, especially at high velocities, and that this is probably not a good thing for breathing. On this score, neither the Coventry Climax motor nor the BRM motor are a success, but the Cosworth DFV 3-litre V8 fits well, as did the 3.5 litre V10 motors used in F1 up until some time ago.

In any case, the BRM kit, while in 1/43, is quite detailed and is mainly spun-cast white metal. The box is barely 6" x 3 1/2" x 2" but it looks as complicated as the Mosquito. The 4X magnifier will come in handy.

All in all it is a Good Thing that I am retired... Stay tuned!

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