'Old Nail' Vauxhall Firenza..., My entry for the pre-76 saloons event at Wolves... Options

[MAF]

Here’s the story of how I got my body done for my entry for the Wolves Pre-76 saloons event which is next month. I thought I’d take some pics as I went along to help those thinking of doing body mods and casting their own car.

My entry will be the Firenza Droopsnoot ‘Old Nail’ of the DTV racing team driven by Gerry Marshall. As a few of you will know this is not my area of expertise (pre-war is my thing) so a lot of research has gone into this one and hopefully I’ve got the car somewhere near how it would have been. I’ve taken some info off various sites which to the best of my knowledge is correct and pasted below to give some background on the car and its larger than life driver Gerry Marshall….

Dealer Team Vauxhall, Gerry Marshall and Bill Blydenstein
“Gerry Marshall and the cars of Dealer Team Vauxhall dominated British saloon car racing for a decade after Bill Blydenstein won his first race in a Viva in 1967.
Gerry Marshall was (and remained until his death in 2005) one of the great larger-than-life characters of British motorsport. Famed for his compulsively entertaining sideways' driving style and his easy relationship with the press, Marshall is now considered one of the great motor racing drivers - a reputation he cemented whilst racing for DTV.
Gerry Marshall's partnership with Blydenstein led the pair to instant track success and it grew with each passing season, as the former gained experience at the wheel and the latter tuned, tinkered and fitted new parts to the cars. 1970 was an especially good racing year, and it was based on this success that a consortium of Vauxhall dealers approached Blydenstein in 1971 with an offer of sponsorship.
This moment was the birth of Driver Team Vauxhall, a production car racing team that had no official backing from the manufacturer it represented (the consortium of dealers sidestepped Luton completely, funding the DTV direct from their own coffers), yet would establish it in the eyes of the public as the premier force in production car racing”

‘Old Nail'


“1971 was also the year that the team switched to Vauxhall's new Firenza' body style. The new car kept up DTV's run of success admirably, thanks in part to the many engine and other component changes instigated by Blydenstein. Notably for spectators, it gained the famous ‘droopsnoot' nose section in 1974, to complement Vauxhall's aerodynamic new production model.
In fact, the car chalked up so many victories in the years up to 1975 (winning a total of 63 races and several Super Saloon championships) that it began to acquire a celebrity following of its own. ‘Old Nail' as the car was known was Marshall's most prolific winner, and DTV was later to present it to him personally as a memento of those victories.”

According to my research Old Nail still remains with Gerry’s family and here is a picture of it in retirement, apparently the car is in the condition it completed its last race and hasn’t been restored in anyway….


So onto my slot car rendition for the Wolves event, I’ve documented the build with pics as it may offer some info for other builders or encourage others to give it a go….




It started off as the OCAR resin kit, this is the standard road going version which was raced as is but to do Old Nail it needed extensive modifications to the wings and other bit and bobs. Firstly the wings, I attacked this first by super gluing plasticard strips to the wheel arches and shaping these in accordance to the many pictures I gathered to give me a reference to fill to…





If the car just had extended arches this can then be filled and blended into the bodywork as below…



…but this car has different front and rear wings to the standard road going car so another piece of plasticard is glued to the body, shaped and measured, again to provide a reference to fill too and ensure both sides are equal. This pic shows the plasticard stuck on before shaping to the right profile...



This plasticard is shaped in accordance to the pictures of the real car and now gives me two planes of reference to fill to and once sanded and blended to the car looks like this….



Next step is too fill the upper half of the wing and having the plasticard in place is a great help to ensure proportions and symmetry are maintained….



The rear bumper is removed along with the chrome trim around the side windows and on the sills….

Cut-outs on the bonnets are next and these are marked up and cut out with a dremel and finished using needle files…





A rear spoiler is added which was fashioned out of piece of PCB board..



The last mod to the car is the rear air intakes on the wings which were shaped out of two pieces of plastic and glued and blended to the car..



So now it’s due for a coat of grey primer to show up all the errors and places where attention is needed…



There’s nothing like a coat of primer to show up all the problem areas so the cycles of filling - sanding - primer begin until I’m happy with the car…





Next up is to take a casting of the modified body so I’ll have a strong light body for racing, here’s a picture of the car clayed up (with plasticine) ready for moulding…



It’s important to leave a approx ¼” based on the car and to set back the window opening to the desired thickness of the cast shell, this set back will end up a ‘male’ in the silicon mould and will give and indication of how thick the casting is and will leave the window openings with only a thin layer of resin making it easier for clean up. The ¼” base is needed to ensure when you come to cast in resin you have some barrier against the resin flowing out of the mould when you ‘slush’. After claying up a box around the car has to be built, I use Lego for mine as it can be reused and broken down easily however pretty much anything will do; I’ve used the shiny side of cornflake boxes etc to make boxes too…



The box must be sealed to the surface; I’ve used hot glue on to an old picture piece of glass to complete my mould box….





So onto mixing up the silicon for my mould here’s a pic of the materials used…



This silicon is form Tiranti’s and is the T28 variety. The silicon is mixed with an activator and 20:1 by weight and slowly poured into one corner of the mould…



In this excellent pic taken one-handed whilst pouring you can see the slow trickle of silicon going into the mould, it will take a long time to fill the mould but its worth it because you will not get any air pockets in the mould and the bubbles in the silicon will have a chance to rise….



It’s a good idea to have some sort of rest set-up so your arm doesn’t go numb!!!

Once filled you can see immediately air bubbles rising to the surface….



To aid this I normally place it on the tumble dryer for 20minutes to give some vibration to the mix…



Then its left for 24 hours until ready for demould when the Lego wall can be broken down and the pattern gently eased from the mould….



So now we have a mould ready for casting the new body. Material used for the casting are again form Tiranti’s and is the Axon F16 type….



The resin is mixed 50:50 by weight and for the first slushing of approx 10 grammes the resin is painted into all the nooks and crannies and across the surface of the mould to ensure a bubble free surface finish…



Then it’s a case of mixing small amounts of resin at a time and slushing in the mould until a desired thickness all round is achieved…



I’m always inpatient when it comes to releasing the casting form the mould so after 30 minutes or so the casting is released….



And we now have an exact copy of the original pattern. Next up is to clean up the flashing and open up the window openings…



And after all that we are now back where started and have a body ready for mounting to a chassis…



There’s one notable difference between mine and the original though (apart form all the mods that is) and that’s that mine although now bigger weighs in at 30 grammes and the original OCAR kit weighed in a 44 grammes - a saving of 32%, all relative of course but mine is for an entry into a racing event so the lighter the better for me! It could be lighter but I’m happy with it as is, the last thing I want is for it to explode into a dozen pieces on the first off (which is usually the first corner!)..

That’s all until the weekend when I can get some paint on it and tackle those Castrol stripes!!

[Swissracer]

Stunning! and some great tips in there, thanks MAF.

The only thing you missed and something I would love to know... What do you use for filler?

[MAF]

The only thing you missed and something I would love to know... What do you use for filler?

Hi Allan, thanks, I use normal two part car body filler, P38 here in the UK. The yellow stuff you can see is spray putty (again an automotive product) painted on with a brush.

[JaakBeentjes]

Thanks for sharing this very informative thread

looking forward to next installment.

[tifosi]

Super work Marlon - but have you checked with Phil Insul about eligibility?

I think Old Nail was a Super saloon (Not sure but certainly NOT Group 1 but it might have been eligible for Group 2 status?) and DTM wide arch and silhouette type cars are not allowed.

Not for me to say but I would have thought Special Saloons were also excluded.

I hope not for I really look forward to seeing this car compete complete with the Castrol livery.

Look forward to future posts and pics.

[BEEJAY7]

Fantastic Marlon......One of my favorite cars.

Regards

Alan

[MAF]

Thanks guys. I do hope it's eligible as I have nothing else . It's within the dimensions stated i.e. overall width including arches etc so thought it would be OK, I'll check with Phil.

[Hobby]

Hi Marlon,
Fantastic craftsmanship.
The amount of work you have put in to achieve such a result should not be underestmated.
Looking forward to seeing the finished masterpeice at Wolves.
Kind regards Bill.

[DH71Tiger]

Excellent work MAF

I have learned a lot from reading your post....................

It will be useful to me when I come to cast my Lotus 33 shells.

Thank you very much for sharing.

Tally H

Andrew

[zagato]

Ten out of ten Marlon. Excellent work me old mate! What silver are you intending to finish off with? Regards, Graham.

[scudbong]

Marlon,

Thanks for sharing your techniques, you make it look so easy! This is an excellent thread, very inspiring and i look forward to the next installment.

Thanks again,

Pete

[taxi]

Lovely work Marlon, terrific to see the process and techniques. But you make it look so easy, couldn't you at least say it was hard work or something?

Looking forward to seeing the next steps.

cheers,

Rob

[DJ]

Great topic, very informative and inspirational, bet it's not as easy as you make it look.
Can't wait to see the finished model, really hope you get to race it. (perhaps we'll have to start a petition if they turn it down.!!)

DJ

[tossedman]

Great work Marlon. Thanks for sharing. You make it look so easy. I've tried it (using both hands, not holding a camera with one) and know it's a lot of work. Well done.

Cheers,

Todd

[Phil.Insull]

Marlon,
Given the work involved and the fact that it is well within the dimensions i think we can let it run as a group 2 saloon.
Cheers
Phil