MG Metro 6R4: quite the little bomb

I managed to find a model kit, from Profil 24, of one of the most outrageous little rallye cars ever built, the MG Metro 6R4. The street version of the Metro was allegedly the successor to the original Mini but turned out to be one of the biggest pieces of crap ever perpetrated on the automobile-buying public. However, shoving a 4-cam V6 into the trunk, and tacking on huge fenders, air intakes and spoilers made it into a proper little monster: https://www.youtube.com/watch?v=bwvDFvLiIqQ 

Watching people standing around as these things get airborne over a rise, i.e. completely out of control, is frightening. Let’s hear it for opposite lock and throttle-induced oversteer! It’s hard to imagine the wings and associated aero bits doing any good given the relatively low speeds. More here: https://www.youtube.com/watch?v=hrlhepfy9-I

 

 

I recall hearing a rumour years ago that the 3-litre V6 was later inserted (in 3.5 litre, turbocharged form) into the Jaguar XJ220, a rumour hotly denied by Jaguar. An MG motor in a Jag? A scurrilous allegation undeserving of attention, you contemptuous little scalawag. Jag claims the XJ220 motor came from the XJR 11 Le Mans car, which I don't doubt, but where did the Le Mans engine come from? (The XJR 9 had a 7.0 V12 based on the old Series 3 E-Type motor, and did well enough, but eventually they needed something more modern). To the best of my recollection, the British Leyland empire had no experience with V6 motors, especially not 90 degree V6s based on Cosworth DFV architecture, and it seems unlikely to me that they would have gone out and designed two such motors from the ground up. There is lots of room for conspiracy theories here; to help muddy the waters and add fuel to the fire, I also have Tamiya's kit of the XJ220 and perhaps I will assemble both motors simultaneously, looking for differences and/or similarities which I will duly report here.

 

I’ve got a series of kits of these monster little Group B cars and will get around to building them at some point. I’m really only missing a Renault Turbo 5; I passed on a curbside kit of the Turbo 5 by Heller a number of years ago when in Toulouse on business, because it had no engine detail; I am still kicking myself today. The Peugeot 205 in the photos is a Tamiya kit which I completed some time ago, and the others are described in earlier blog posts.

 

 

The MG is  a resin kit and my success rate so far with these is poor, so don’t expect any progress in a hurry; I picked it up because it was the one of the last ones they had and if I had waited it would have been gone by the time I was ready for it.

 

 

So another project for retirement, which will apparently be busy: including a Cheetah which is on order from Historic Racing Miniatures, I now have exactly 100 kits which are either not started (84) or partially complete (16), with another 54 completed and in the display case.

 

The complete rally collection:

 

Completed:

Alpine A110

Lancia Stratos

Morris Mini Cooper

Peugeot 205 Group B

 

Not started or incomplete:

Audi S1 Group B

Ford Falcon Sprint

Lancia Delta S4 Group B

MG Metro 6R4 Group B

Peugeot 206 Group B

Talbot-Sunbeam Lotus Group B

Toyota Celica Twin-Cam Turbo Group B

 

3D printing,continued

So now Dremel makes a home 3D printer, see here.

Still not cheap but not completely out of line if you are a serious hobbyist. The pros and cons of 3D printing versus casting yourself are sure to be a growing topic.

Now where is that Hewland gearbox I wanted to replicate?

Abarth OT 1300: chassis complete

The suspension front and rear has come together and I was able to mock it all up. It looks good; the rear track may need narrowing by means of grinding out the inner wheel such that the wheel can be pushed over the stub axle and disc a bit more. It is about the size of a Lotus Europa which many of you will know is tiny; the Mini of the same vintage towers over both of them.





A reader posted a comment asking about the source of the kit. It is from the Japanese manufacturer Model Factory Hiro, where it appears it is no longer listed (click here). I may have gotten it from Strada Sports although to be honest I don't see it on their site either (click here).  Interestingly, Island Collectibles list the Abarth as a curbside (click here and scroll to the bottom) which it most definitely is not. It is indeed a very nice kit, and is one of those things that if you see it, you should grab it regardless of price because there likely aren't a lot of them out there. 



It's a so-called multi-media kit because it includes parts of spun cast white metal, resin, vacuum-formed clear plastic, photo-etched sheet, some odd hard metal chrome, etc. As with a lot of these companies, the instruction sheet is vague and lacks detail; you need to do a lot of trial fitting, filing, drilling out of little holes, filing of dowels, etc. In the end it is well worth it because you get something unique and the build is challenging.



I also have a couple of early Porsches (908/03 and 917K) and a Cobra Daytona Coupe from Model Factory Hiro. I have started on the 908/03 (see this blog starting here) but it is a monster and you should practice on simpler multi-media kits first. The 917 looks to be equally complex; the Cobra should be simpler. I got the Cobra from Strada Sports, and the Porsches from Island Collectibles. Unfortunately, MFH seems to be moving to all 1:12 scale; the detail is presumably mind-blowing but at really exorbitant prices, and it will take up a lot of space in your cabinet.

Stay tuned. The interior looks pretty straightforward, then it is on to the body. The weather is still cold here and progress is still possible before us winter-weary Canadians all head en masse to the deck.

Abarth OT 1300: Engine compartment complete

With lousy weather prevailing, progress on the OT 1300 continues at a rapid pace. I am not sure how long this will last, so I am working on getting as much done as quickly as possible.



The engine is installed, along with all the bits except for the muffler which will go on last. I had trouble with the braided hose, which is either too small or too big (3/4" at scale) and for now have not plumbed up the remote oil filter mounted on the left rear fender.

It's all looking pretty good and mocking up the wheels with the central body section is pretty exciting. The little periscope for cockpit ventilation is cute if a bit silly.





It's tiny, with the Lotus Europa, complete with trunk, looming over it. The picture shows a total of 16 cylinders, roughly 6.5 litres, somewhere around 450 hp between the four of them.

In a similar vein, I once had the pleasure of driving a Ginetta G15, with the Hillman Imp drivetrain which was a street version of the lovely Coventry Climax engine. With a short-stroke aluminum block, wet liners, aluminum SOHC head, a pair of little Webers and ~100 hp from 1100 cc, the Coventry Climax motor was a lovely little unit and found its way into all kinds of classic items like the Lotus XI. The Imp version was sleeved down to 875 cc with two Strombergs CDs, probably about 50 hp, all to fit under the tax limit in the UK while also competing with the Mini at 850 cc. The motor was far more advanced than the Mini's long-stroke, iron block with siamesed 8-port head, but the rear-engine design of the Imp doomed it from the start when compared with the massively space-efficient FWD design by Alec Issigonis.

Of course as one of the few people in North America to have even seen a Ginetta, let alone driven one or worked on one, I can honestly claim to be something of an expert. A Ginettacist, what! Ha ha, get it, geneticist/Ginettacist... OK never mind. Twin-cam fours forever! I've got a resin kit of an Offy motor on order.

UPDATE: Photo of the front axle in response to a question posted by Aurfalien. Part M57 certainly appears to be present and accounted for. 

Update #2: Photos of the carb side of the engine in response to a question posted by Aurfalien.

 

Hope this helps!

Abarth OT 1300: engine progress

Progress is being made. The objective is to complete at least one resin kit as a morale booster, before going back to face the monster (and monstrous) 908, or one of the many Profil 24 kits sitting on the shelf.



The engine is essentially complete, lacking only exhaust pipes before I can insert it into the chassis and finish up the engine compartment. (The flat white paint is drying). Note the large oil reservoir, about 7 litres at scale, bolted to the block below the carbs. There is also a proper deep sump, so while not a dry sump, it certainly carried several gallons of oil.



The plug wiring is a bit messy, but I am quite pleased with the alternator belt. Once installed in the engine compartment, there are a range of bits such as remote oil filters and fuel pumps that can all be connected, and I do have some braided hose, so maybe I'll get carried away.

The instruction 'sheet' is pretty amusing. It consists of a single 8 1/2 X 11 sheet, printed on two sides, showing the various components and where they go; and two more sheets printed on two sides with a total of 16 colour photos of a specific 1:1 car, all taken May 16, 1993. This is where you get the information around colours, hoses, etc. It would be interesting to know which specific car is modeled here.

It's getting exciting. Stay tuned!

Abarth OT 1300: first steps

Having an afternoon free, I decided to tackle one of the resin kits on the shelf. I have three such resin kits under way, and an obvious step would have been to pick one of these up and carry on, but all three are bottlenecked at points where I had to walk away before getting frustrated. So I decided to avoid past frustrations and tackle what appears to be an 'easier' resin kit, the Abarth OT 1300 Periscopio by Model Factory Hiro.



Regular readers (if any) will recall I described the kit when I got it almost a year ago, in May 2015. The resin consists of four large, very well made body parts; the surfaces and fit are so good that they could almost be styrene. There is a substantial amount of white metal, mainly engine bits; so I started with the engine.



The little twin-cam conversion looks good; the granularity due to the spun-cast white metal mold convincingly mimics a coarse aluminum block. Paint consists of Tamiya fine primer, Tamiya gloss aluminum, and a coat of Testor's dullcote (I was out of Tamiya). The instructions are not clear, but the block may have been painted iron if, as I suspect, it came from some lowly Fiat or Simca. To be verified.



A nice surprise is a plate with all 8 spark plugs poking up through 8 holes in the cylinder head. (It's a four cylinder, of 1.3 litres displacement, but with the twin-plug head typical of high performance Italian motors of the period).

Unfortunately the distributor posts are big, while the spark plugs are small. I've got the distributor wired up and will next have to deal with the spark plugs as well as the blackened plug wires where the mini torch was needed for longer than I would have liked to collapse the shrink tubing. (The photo shows the hollow transaxle casting which will not be visible once it is in the car).



On to the body parts. Cleaning them in isopropyl alcohol revealed no big brown goobers as with other resin kits. Tamiya fine primer, followed by Tamiya Italian Red looks good. The chassis got a coat of semi-gloss black, unlike the pale blue-green in the photos provided with the kit. (A couple of blobs of mold release agent turned up here, so clearly a good cleaning is still needed with these kits, no matter how good they look.) The two coats of paint will dry for the next week or so before I can find time to get on to the interior and engine compartment details.



 All in all a reassuring start, although I am sure lots more challenges await. The Cobra Daytona Coupe on the shelf, also from MFH, looks to be of similar 'simplicity' especially when compared to MFH's fiendishly complex 908 and 917. I am coming to the conclusion that the real complexity lies in the space frames in the Porsches, and the fact these chassis bits are modeled in flexible and easily damaged white metal rather than the simpler Abarth and Cobra chassis.

Of course I am probably drawing the Wrath of Murphy by pre-supposing this will all end well. Obviously it won't, but progress to date has been relatively quick and painless.

3D printing: it's coming, and it will revolutionise this hobby

Don't believe me? See Peter Wingfield's site here: http://www.scaleautoart.com/. In particular see the series of software images he used to develop the body for the so-called Ferrari Breadvan, here: http://www.scaleautoart.com/workbench.php?cat=build-diary/112-ferrari-250-gt-breadvan-3d-project. (Thanks to the folks at Profil 24, who have this link on their web page).

So what's a 3D printer? It's a device for spraying little droplets onto a surface, under the control of a computer program that tells it where exactly to put each droplet. This is the same way your inkjet printer sprays little ink droplets onto a piece of paper, except the 3D printer sprays little droplets of melted polymer, and allows them to build up, layer upon layer, into a 3D object instead of a printed 2D sheet.

A decade or so ago I visited the laboratories of the mechanical engineering department in a major Canadian university. They had an early, home-made 3D printer that cost somewhere in the vicinity of $250,000 to build, and that was with lots of cheap graduate student labour. Given the costs, they were predicting rapid prototyping would be the first uses of the technology, so a company could verify things like fit and ease of assembly prior to committing to a production line using conventional injection molding or other methods. As a souvenir, they gave me a small, functioning adjustable wrench which is really quite clever: there is no way they could have made the three components separately and assembled them, because it is impossible to insert the little geared roller into the body; they had to have been deposited at the same time.



At that time, the polymer filament, which is fed into the printer off a spool that looks like a Weed Wacker thread, was the big issue. It has to melt at relatively low temperatures but solidify quickly once deposited, and this limits the properties of the finished product. It is also fairly granular due to the size of the droplets, as you can see in the image above. So it might be dimensionally stable but might not have the visual, mechanical or thermal properties necessary to replace a finished plastic product. Hence the limitation to prototyping, not production.

Fast forward to 2016 and Staples offers a home hobby system by MakerBot for about $2000, click here, that will make objects that fit inside a 4" cube. (MicroMark used to offer a cheaper hobbyist-type system but now I can't find it on their website -- maybe the customer complaints were too much.) The resolution of the MakerBot system is 0.2 mm, about 0.008", so still a bit coarse; you can see the pattern of the traversing print head in the pictures of Wingfield's 250 GTO Breadvan if you zoom in. The resolution will be at least partly due to droplet size, but also probably to the resolution of the stepper motors used to shift the print carriage from one track to the next -- pay more and get better resolution even if the droplet size is the same. Recall how happy we all were when the 8-pin dot matrix printer was replaced by the 9-pin system...

Software is a separate purchase or you can use the free software that comes with it; there is also an industry-standard file system just like JPG or PDF standards, so you can download stuff off the Internet. Finally there are home systems that you can use to scan and digitise an existing object, say for instance a Hewland gearbox which no one seems to make in 1/24 or 1/25 scale; Staples offers a MakerBot scanner/digitiser for about $1100. The real challenge would appear to me to be in making something as thin and flexible as a model car body -- transaxles would likely be a lot easier. I haven't seen Wingfield's models in the solid plastic but I am guessing that he has made significant progress in that area, probably by first deciding where to start depositing drops.

This will likely require all kinds of fiddling, both with the type of polymer used and the computer program. In fact it reminds me of early home printers, which were expensive, finicky and produced low-quality results. Compare that to today's ink-jet printers which are cheap, plug 'n' play, and produce publication-grade images.

I'm excited. It's the next step towards the transporter beam in Star Trek: first we stopped buying books because we could download and print them on a dot-matrix printers; then we stopped buying CDs because we could download and burn them in a CDR writer; now I'll be able to download and print toys for my granddaughter, not to mention kits of every possible obscure car you might care to imagine. Who knows what we'll digitise and ship next, byte by byte, over an expanding digital network...

If I were Jimmy Flintstone, I'd be digitising stuff like crazy and offering the digital models for sale online: $15 for the digital file to make a Cadalicious body to go with your Revell '59 Caddy kit, $20 (plus shipping) if you want a hard copy printed and shipped to your door. First one in will build the reputation and the customer base. And maybe he can fix the quality of some of his bodies while he's at it ...