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I found these three:



They all have the mold line running through them. How is it the shutlines on the Elite are sharper on the outside? I thought in vacforming the plastic was sucked down over the master, but it seems like there was also some female mold that went on top of these. I'm not at all familiar with the vacforming/moulding techniques please excuse my ignorance!
Also some of the MRRC shells look similar to ones that were sold by Autohobbies.

Cheers,
Tom
 

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QUOTE (tomwysom @ 4 Aug 2011, 19:38) <{POST_SNAPBACK}>They all have the mold line running through them. How is it the shutlines on the Elite are sharper on the outside? I thought in vacforming the plastic was sucked down over the master, but it seems like there was also some female mold that went on top of these. I'm not at all familiar with the vacforming/moulding techniques please excuse my ignorance!
Also some of the MRRC shells look similar to ones that were sold by Autohobbies.

Cheers,
Tom
Vac forming can be done with either a male or female mould. Male moulds are standard practice in modern vac formed body shells.

A male mould looks like a solid version of the finished body, the plastic is sucked down over it, and the finest detail is on the inside of the shell.
A female mould has a cavity the shape of the finished body, the plastic is sucked down into it, and the finest detail is on the outside side of the shell.

Both types of mould are sometimes in more than one piece, particularly if there are undercuts on the finished shell that prevent it being released from a one piece mould. In the best example of the mouldmakers art, the joins can be in places where they don't show.

It looks like the Elite was made with a two piece female mould with the split straight down the centre line.
 

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Just what I was thinking- with plastic that thick, the only way to get any detail on it would be with a female mould. Then you have trouble with undercuts etc, especially with the rigidity of the plastic. So you make a two part mould for ease of de-moulding. But two questions- why use plastic that thick to begin with, and why put he join right down the middle, instead of along the shut lines? Answers might be that they didn't have much choice in materials available back then, and that the bodies were intended to be painted on the outside, so sanding out the moulding line was not a big deal. Except where it runs down the middle of the screens...
It's all very easy with hindsight. MRRC were true pioneers!
 

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i have pics on here somewhere of the mrrc clear corvette - from Tom - at the onset i didn't think it would turn in to much - but it turned out very nicely and surprised me with its detail etc

it has the seam down the middle (i didn't think to sand it ... doooh!)

also on here somewhere is my version of the red shell Don posted - another from Tom and another great little vintage shell

thanks again Tom

will see if i can turn up the pics

likewise the green jag in pic tom posted also turned out very well to my eye once i detailed a bit more

but then i like them toylike with their vintage feel intact!

cheers, Ron
 

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Back in 2011 we were discussing MRRC vac shells and there were comments on the thick material used for the second series.
Seems it was acetate. I've just noticed that that's how it's described in a 1967 MAP book, Model Cars Encyclopedia.
There is a photo of about eight shells in the book. It's poor but maybe worth showing. Tony/Superhornets gave us a list: "like the alfa of robs ,and they did things like lotus 19s ,corvette stingrays, ,auto union d types ,lotus elites, ferrari breadvan,porsche spyder,birdcage maser ,coper climax ,1961 ferrari F!,.despite the fact that the plastic was quite thick .these were of fairly good quality ,with as rob says louvres and things".
On the bottom left may be the Alfa and beside it perhaps the Auto Union D-type facing the other way, with the Cooper bottom right. Tell me if I've got it wrong, and feel free to ID the sports-cars.
Confirmation that female moulding was used for these: Robert Schleicher described the Alfa shell I showed earlier as female moulded.
Rob J

 

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Hi,this discussion is very interesting since it covers the first vac bodies made. Heres some from my museum. 5 vac bodies from MRRC and 1 from Super Shells. Ist photo- MRRC Aston Martin rail car sealed on the card. 2nd photo-a Aston Martin on top with a BRM at the bottom both MRRC. 3rd photo-2 Maseratis by MRRC. 4th photo- the underside of 1 of the MRRC cars. 5th -a vac body Lotus made into a rail car by the founder of Super Shells G.K.Jarvis.This actual car can be found in Roger Greenslades book on page 28. thanks,Bernard
 

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QUOTE (Rob J @ 27 Feb 2013, 06:07) <{POST_SNAPBACK}>Back in 2011 we were discussing MRRC vac shells and there were comments on the thick material used for the second series.
Seems it was acetate. I've just noticed that that's how it's described in a 1967 MAP book, Model Cars Encyclopedia.
There is a photo of about eight shells in the book. It's poor but maybe worth showing. Tony/Superhornets gave us a list: "like the alfa of robs ,and they did things like lotus 19s ,corvette stingrays, ,auto union d types ,lotus elites, ferrari breadvan,porsche spyder,birdcage maser ,coper climax ,1961 ferrari F!,.despite the fact that the plastic was quite thick .these were of fairly good quality ,with as rob says louvres and things".
On the bottom left may be the Alfa and beside it perhaps the Auto Union D-type facing the other way, with the Cooper bottom right. Tell me if I've got it wrong, and feel free to ID the sports-cars.
Confirmation that female moulding was used for these: Robert Schleicher described the Alfa shell I showed earlier as female moulded.
Rob J


The sports car third from left is definitely the Corvette Stingray, the one to its left could be the Porsche Spyder and the one to the right of the 'Vette is probably the Lotus 19. Not sure about the one on the far left - not a birdcage Maser or a Breadvan Ferrari. Possibly a Ferrari 250 Berlinetta?

DavidHack
 
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