1:12 scale 1966 Ford GT40 , 1931 Alfa Romeo 8C 2300 and 1:18 scale 1967 Ferrari P4

simond

Western Thunderer
Peter,

indeed, didn’t it just! I’d put myself in both categories, but as I said in the original post, this vehicle is well outside my field.

I entirely missed the two longitudinal links connecting the underside of the axle to the chassis rails, which would effectively stabilise the axle fore & aft. Indeed, without shackles at both ends of the leaf springs, the axle would be forced to rotate as it moved up & down relative to the chassis. As these links are more or less in the same plane as the brake pull rods, they will prevent any inadvertent self-servo, or anti-servo action.

The rear axle is apparently pivoted (the UJ effectively forms a ball joint) at the rear of the gearbox. It must therefore move in an arc as it rises & falls, and therefore the springs must not constrain it in the fore & aft direction, so they must have shackles at both ends. The UJ prevents fore & aft movement, and reacts the axle torque under acceleration and braking, and I suspect also establishes the rear roll axis.

Think it all makes sense now.

cheers
Simon
 

Dog Star

Western Thunderer
Re references to prop shaft and UJ... I do not believe that this car had a prop shaft in the accepted sense, rather the diff pinion may well have had an extended shaft running the length of what I think is called a "Muff tube" leading to a joint on the rear of the gearbox which I think was called a "Muff coupling". Of course I may be wrong as my friends say I know "muffing".
 

Osgood

Western Thunderer
Some pictures here of a restoration progress that might yield some useful modelling detail:

Alfa Romeo 8C 2300 Spider Re-Creation

The dual scissor dampers on the rear axle are fascinating!
I think those upper front shackle pins have a castellated nut on the rear (inside) holding the shouldered pin in place.

That red paint is beautiful.....
 

P A D

Western Thunderer
Many thanks Tony. I can't seem to download the images but the webpage is duly saved. Clearly it's a more luxurious variant with the cockpit lined out in leather with a pouch for storage. Several of the images I've found show a leather satchel fixed either to one of the inner walls or to the spare wheel, possibly for storing a Jack for changing a wheel. As far as I know the petrol tank was behind the cockpit so does any body know the purpose of the tank slung underneath the floor. I'm assuming another fuel tank. Or did it have a two stroke engine and the tanks is for oil?

It's a shame that these "industrial " kit makers don't identify the parts by name so the less informed (me for example) can learn a bit more about the prototype. Time consuming I know and not something I would expect from an etched kit maker with limited resources, but I would have thought these big companies could do it.
Cheers,
Peter

20210101_112200.jpg
 

Osgood

Western Thunderer
Check this web page out - I wonder if it is an oil tank. Looks to be 1/8 scale - a work of art for sure!
Andy Marks - Model Motorcars, Ltd.

The site is addictive - e.g.
Alfa Romeo Store

And it turns out they are the guys who have taken over Scale Hardware!
Scale Hardware, Scalehardware - Model Motorcars, Ltd.

Their Youtube videos (scroll down the page) of the Alfa build may well reveal a lot of mechanical secrets about the real car (I haven't watched them yet):
Custom Pocher Models, Pocher Kits and Spare Parts, Free Pocher Manuals - Model Motorcars, Ltd
 

Dog Star

Western Thunderer
I’d go with “Torque Tube”.
Thank you Simon (@simond), I had forgotten "torque tube".... more than 35 years since I last was in the vicinity of a Riley restoration with a similar arrangement. I believe that Muff coupling may be appropriate as that was the description used by the owner of the Riley.
 

class27

Active Member
Peter,

indeed, didn’t it just! I’d put myself in both categories, but as I said in the original post, this vehicle is well outside my field.

I entirely missed the two longitudinal links connecting the underside of the axle to the chassis rails, which would effectively stabilise the axle fore & aft. Indeed, without shackles at both ends of the leaf springs, the axle would be forced to rotate as it moved up & down relative to the chassis. As these links are more or less in the same plane as the brake pull rods, they will prevent any inadvertent self-servo, or anti-servo action.

The rear axle is apparently pivoted (the UJ effectively forms a ball joint) at the rear of the gearbox. It must therefore move in an arc as it rises & falls, and therefore the springs must not constrain it in the fore & aft direction, so they must have shackles at both ends. The UJ prevents fore & aft movement, and reacts the axle torque under acceleration and braking, and I suspect also establishes the rear roll axis.

Think it all makes sense now.

cheers
Simon
Simon
Always remembering that the brakes in question won't generate any thing like the twisting forces generated by the cars of today. I thought it was interesting that the kit springs look decambered which I expected the real ones to be the same, but they were not. I suppose the car in the picture is probably not on its original springs, or perhaps the drawings or vehicle used by the kit manufacturer did. Decambering the springs would get rid of the spring lengthening issue and replaced by shortening, this would be better shared by both shackles. Apologies to the original OP for rambling on what is a very interesting thread!
 

P A D

Western Thunderer
No worries class27, ramble away. Its all interesting stuff coming from the cognoscenti, albeit some of the technicalities are passing over my head.
 

P A D

Western Thunderer
Check this web page out - I wonder if it is an oil tank. Looks to be 1/8 scale - a work of art for sure!
Andy Marks - Model Motorcars, Ltd.

The site is addictive - e.g.
Alfa Romeo Store

And it turns out they are the guys who have taken over Scale Hardware!
Scale Hardware, Scalehardware - Model Motorcars, Ltd.

Their Youtube videos (scroll down the page) of the Alfa build may well reveal a lot of mechanical secrets about the real car (I haven't watched them yet):
Custom Pocher Models, Pocher Kits and Spare Parts, Free Pocher Manuals - Model Motorcars, Ltd

Many thanks Tony. Once again lots of stuff I haven't found in my searches.

Here's a couple of images of the built up 1:8 POCHER kit.
image (3).jpeg image (5).jpeg
 

P A D

Western Thunderer
With the weather being too cold and damp of late for spraying, I've not spent much time in the garage since the start of the new year, so progress has slowed on both builds. However, I've being chivvying away with the brush painting of the engine and one or two other areas. Here's the engine. It's a bit spartan on this side without the exhaust manifold.
20210125_211339.jpg

But it's a bit busier on the other side. The rocker covers are just placed for the photo in this image
20210125_211207.jpg


20210125_211229.jpg

Here's the radiator after painting, with the grill placed to show off the Alpha Romeo signature. It should look the biz when surrounded by the front cowling. The radiator frame was painted with Tamiya silver, with the mesh in gunmetal. As with the engine, priming was with Halfors white plastic

primer from a rattle can.20210125_211120.jpg


Again after priming in white, the cockpit floor and "sofa" were brush painted with Tamiya acrylics. Aluminium for the floor and some brown shade or other, whose name escapes me at the moment, for the sofa. The brown is a Matt paint that I've buffed up with a cotton polishing wheel in the mini drill. Whiles modern automotive finishes on leather are very matt, that was not the case in the 1930s.
20210125_211056.jpg

The weather in Leeds was relatively mild today and with the aid of my fan heater I was able to raise the temperature in the garage to allow me to prime the chassis, wheels and coach work in Halfords red plastic primer. No pics at the minute but I'll take some later.

When it come to painting the bodywork on the GT40 and Alfa, I'll be using Tamiya's solvent based lacquer paints as I've read good things about them in review. I built this 1:24 scale Tamiya Subaru Impreza for my daughter over the Christmas period and the main body colour was done in Tamiya Mica Blue. It goes on very smoothly and gives a result similar to cellulose paint.
20210118_220840.jpg

And to digress even further from loco kit building I've bought another "RTR" item to do up. It's Jouef Evolution 1:18 scale Ferrari 330 P4 spyder. Dimensionally, it fairly accurate and captures the shape of the P4 very well, but detail wise, it leaves a lot to be desired.
20210125_212210.jpg

I'm hoping to upgrade it into a reasonably detailed model eliminating as many of the faults as possible. Just to mention a few of these from the images, the horrendous hinges to the engine cover, the pisspotical windscreen wipers and seatbelts, the poorly fitting headlight covers and the locking clamps on the bonnet.
20210125_211922.jpg

As with the Piko BR64, I've taken a RTR item and turned if into a kit. There's a lot 70 compents and 14 screws.
20210125_162115.jpg

After a bath in Nitromors, the diecast parts look like this.20210127_085143.jpg

I would have preferred a berlinetta version, but picked this up very cheaply on Ebay so I'm considering adding the roof and modifying the doors to convert it. I've seen a couple of YouTube videos which suggest it's fairly easy to copper plate diecast metal to allow it to be soldered.
We'll see.

Cheers,
Peter
 
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P A D

Western Thunderer
So, here's the state of play with the Alfa's main body parts and wheels after a waft of Halfords red (oxide) plastic primer. The outer faces of the drum brakes were primed with Halfords white and brushed with Tamiya acrylic Aluminium.
20210128_190133.jpg

And with the body placed on the chassis.
20210128_190002.jpg

Sofa looks comfy.
20210128_185930.jpg

This is the Alfa dashboard after "chroming" the clocks ready for fitting the decals.
20210128_185835.jpg

Here are the main body parts for the GT40. As I changed my mind and will be building the pale blue liveried Ken Miles car, I've re-primed in white the parts already done in grey, which will be easier to get cover with the top coat.
20201223_163635.jpg

Moving on to the Ferrari P4, I've already done a fair bit of fettling on the castings to remove flash from the edges and open up the various air vents in the bodywork. One of the main eyesores are hideously large hinges between the cockpit and engine cover.
20210127_160644.jpg

The engine cover is a two part casting and the lower part exhibits very ropy edges which show up badly in the finished model as received.
The joint where the castings are screwed together is also very obvious, where there is none on the prototype and the locking catches are grossly over scale. The inner edge of the right hand luggage box impinges into the spare wheel aperture so that will need some attention. The grill at the top edge is cast in-situe and would be a mare to cut out and replace, so I'll live with that. Note also the rear edge of the plastic insert for the vents above the engine, showing along the top edge of the spare wheel aperture.
20210125_212124.jpg

This is the lower casting after stripping
20210127_160706.jpg

Here the vents in the cover are shown as they come cast in-situe and the very obvious joint between the upper and lower casting can be seen.
20210125_211456.jpg

Here are the vents after opening up. The hideous hinges have now succumbed to the file.
20210127_160259.jpg

I've also opened up the vent slots in the lower body panels under the cockpit.
20210127_160422.jpg
This view shows the joint between the lower and upper cockpit castings. Even when screwed tightly the joint is very obvious and is in fact too low down. The joint on the prototype is where the bottom edge of the bonnet is. Note also that I've removed the row of rivets along the bottom edge of the joint as they were way too large.
20210127_160049.jpg
The bonnet is a two part casting and this image shows some of the fettling already done to remove a casting line just above the large front aperture and the two smaller vent slots opened up. The edge of the lower casting overhung the upper one and needed quite a bit of filing to get it in line. Note the flash on the head light apertures still to be tackled.
20210127_155644.jpg
This side on view shows the gap that occurs when the castings are screwed together.
20210127_155738.jpg

Back at the rear, the vents in the engine cover are represented by a plastic insert. It is poorly fitting and the vent holes needed a lot of work with the file to open them up. The rear edge shows where material has been removed to get it to sit up tight in the upper engine cover casting. Ropy work I know, but this plastic doesn't file very well and when its glued in place it will never be seen again.
20210126_185417.jpg

Here it is trial fitted in the engine cover. Note the lack of hinges on the front edge. I've got one or two ideas on how I'm going to replace them but I'll get to that in due course.
20210127_155519.jpg

Well that's my 16 images for this post although I've got more to show. It's not etched loco kit building, but it's nice to be working with metal again.

Cheers,
Pete
 

cmax

Western Thunderer
Peter, it might not be etched loco kit building, but it's still modelling of the highest order, keep em coming!!

Cheers,
Gary
 

P A D

Western Thunderer
So to bring things up to speed here's a view showing the the cockpit castings. The only way to eliminate the erroneous joint line will be to fill an smooth it. This means that I'll need to be able to insert the cockpit interior after painting so converting the model to a berlinetta version is out of the question. Not to worry. I've also removed the over scale rivets up and over the rear cockpit bulkhead. On the prototype they are not dome head rivets and are not that prominent, so I'm going to ignore them.
20210127_155828.jpg

Here's the bonnet trial fitted. I've opened up the small vent below the inner edge of the left hand wheel arch and will need to fill the holes for the plastic catches that I will not be using. I'm going to retain the bonnet with an M 1.0 machine screw, screwed into a hole drilled in the cockpit casting. I've got a small set of metric taps on order.
20210127_152840.jpg

Moving on to some of the plastic parts, here's the front suspension with the keeper plate below. Very crude and unprototypical.
20210128_142851.jpg

And with the keeper plate in place. The steering rod should be to the front not the rear.
20210128_142929.jpg

With a bit of fettling and jiggery pokery I was able to reverse the set up so the steering rod is at the front. The wheel hubs have the mounting for the disc cooling pipes to the rear so I should be able to fit those.
20210128_153029.jpg

20210128_153150.jpg

Here's the basic body shell minus the doors.
20210127_155913.jpg

Cheers,
Peter
 
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