2014 Tasman Cup Car builds

[Stubbo]

Here are the two new builds underway for Stubbo and Slo1quick.



Still a bit of work to do. but they should be done by the 28th.

Stu has been having a bit of trouble getting the mounting post right.

He was using my glasses! Hopefully he can find a ruler and a knife. It aint gonna fit otherwise.

[David Lawson]

I like the two colour schemes Alan, what cars are they and who raced them in the Tasman Series please?

Are the shells converted from the old Atlas shell or are they resin?

David

[slo]

David, as the Vraa cars are eligible for the Tasman series and they are GP based, there is a certain amount of license pertaining to specific race car authenticity.
These cars are close replicas to the  Brabham Bt11a. The red one is based on Graham Hill  and the classic green and gold is based on Jack but I quess it could be Denny Hulme.
Graham raced the #2 at Pukekohe in 65' but this car will wear #1 as Stubbo is the reining champ. The green and gold will wear the #3 which is my preferred #. I'd like it to commemorate Jack.

Here are a couple pics of the chassis that a destined for the Graham Hill car

[Stubbo]

Update. Starting to look a little better. Getting all the other bits like roll bars, inserts, windscreens etc done over the weekend.

David, The body is a resin that I have made. It probably did originate from the Atlas car but there have been a few versions and recasts etc along the way. This one was done to try and replicate the cars as they appeared in the Tasman Series with the 2.5 litre engines.

[David Lawson]

Thanks for the extra details, the chassis is looking excellent.

I thought the red car was a Graham Hill version but wasn't certain as I only have a b&w picture of it. According to one of my books it was a Brabham BT3 and Graham raced it for Scuderia Veloce in 1964 and 1965 winning several races.

David

[Stubbo]

A lot of the info is gained from this site.

www.sergent.com.au

Generally as I understand, a BT3 would be called a BT4 in the Tasman series and the BT7 and BT11's were BT7a and BT11a.

But as always there may have been other variations or model numbers.

I know Hill was in a BT4 in 1964 and I believe it was a BT11A in 1965.

[f143]

The finish on the bodies looks first class Stubbo, and the chassis looks very interesting. Is it a tried and tested design, or is it an original from your fertile mind?
Cheers
Nigel

[Stubbo]

Thanks Nigel, I'll accept the compliment on the bodies but the chassis is the brainchild and handywork of Stu. I'll let him tell you more about it.

[slo]

Thanks Nigel. The chassis is based on our first VRAA Brabham entries, subsequently those chassis were used in the last the two Tasman series so far. Those chassis have proven to be able to run with the best of them, although I didnt build the front ends strong enough for the rigors of proxy racing, as such they had to be repaired quite often. This chassis is quite different in that the main core of the chassis has been silver brazed at a high temperature and is very strong and it doesnt fall apart when adding the ancillary components such as the suspension ties, etc. The pod idea was born out of the frustration of failed attempts of components breaking because using this high a temperature messes with the natural temper of the piano wire, and the brass. It makes the piano wire brittle and seems to anneal the brass. The main concern is the brittle wire breaking. The front end is strong and no fuss, however, pod enables the addition of separate wire chassis rails that are soldered with an iron that does not alter the temper of the wire. The pod and front end are rigid and dont flex but the flex is in the rails so no problems there. The addition gibs that hold the pod in place allow for the pod to be independent of the chassis rails and allow for wheel base adjustment and float. The float of the pod can be adjusted, while in turn, can also be used to adjust the flex in the rails.
It has taken many frustrating hours and failed attempts to come up with this simple looking chassis. There is nothing more frustrating the being well in a build and then do something silly and stuff it up. This way only half the chassis is ruined.
The only testing was last weekend when Stubbo and I were able to meet up at the Cape to bring the chassis and bodies together to make sure everything was going to fit ok. Given good tyres we are happy with it so far. It is nice to drive and is a good basis for modification and tweaking.

A pic of the brazed main core of the chassis, the center peice of tubing is cut away later.


some parts are brazed independently so when soldered to the main pod they dont fall apart.


The other pod is based on A Bt4 and from previous testing, found to be to light for a spirited solarbotics This is were we found problems in the annealed brass axle bushing to have excessive  wear. By placing the components in a tumbler using stainless shot with a burnishing compound for a couple hours I have found that this massaging action peens the metal back into its more natural temper, the brass does not appear to be as soft and the wire so brittle, but we'll see how things hold up.

[f143]

Ah ha, all very high tech approach, no wonder you fly the Aussie flag high in results. But, I was expecting you to say, ahhh just a couple of pieces of fence wire I had left over!
Lovely job, look forward to seeing how they run in the competition.
Regards
Nigel

[Phil Kalbfell]

Unfortunately the temperature required for the silver solder is above the critical temperature of the spring wire, so characteristics of the wire is changed.
The extra strength of the silver soldered joints does make things more reliable and easier to add suspension.

[old23]

Stunning work guys!

[Stubbo]

Stewart, just letting you know your parcel arrived today.