Shelby GT350R

KensRedZed said:

Thank you Wobble. You would make a good Canadian, eh?

AMT makes a 1/32 notchback version of the 64-Mustang. The exact car you're looking for. Extremely easy to convert to a slot car.

Nice looking billet slot car EM!!

My first aluminum chassis was made on a Bridgeport. Then I had to figure out how to get the same precision at home without it. It was a fun challenge.

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KRZ, your experiments and evident success have prompted me to go back and think about the question of "handling" in the slot car world.

Now, I understand that because the path of the front of the slot car follows a fixed locus of points, the physics of handling of the slot car and a 1:1 car are very different. Certainly, factors like center of mass, lateral weight transfer and downforce figure into both but in different ways and to different degrees.

I started out by assuming that since rigidity was a "good" attribute in the 1:1 car, the same would apply to slot cars - thus my billet aluminum approach. I had not gone much beyond that prior to dropping out of the slot car world in about 1965 and not returning for 30 years.

In '95, I started looking and reading and found out that all manner of things that transpired - flexing, flopping, shaking and rattling chassis and loose bodies were de rigeur even when one moved away from doorstop shaped missiles. At that point the commercially available RTR cars such as Scalextric and Ninco were pretty basic plastic platforms. I started building again, experimenting with pivoting chassis and floppy pans. It was pretty easy to come up with a brass/wire chassis that will outrun the out-of-the-box cars.

Things on the commercial front have changed and now RTRs are offering all sorts of controlled movement etc. and it is certainly no longer as easy to outrun them. The benefit of these innovations is assumed. As an example, locally we run a class for 1962 and earlier sports cars. Commercial and scratch built chassis are permitted but, if the commercial chassis uses a motor pod, it must be locked down.

Now, your designs appear to offer 2 things: they are absolutely square in the X, Y and Z axes and, since the light weight affords the opportunity to add ballast, the center of gravity is very low. This seems to be going counter to history and evolution - like going into a pet store and finding a Dodo bird for sale.

Now, as always, it is "horses for courses." What does your club run? What are the rules? Have you run your cars against more "sophisticated" designs? The results?

In sum, I need to decide how to divide my efforts between completing what I have currently on the bench - front and rear brackets, wire rails and rattle pans - and climbing the learning curve for my recently acquired Taig CNC mill.

Thoughts?

EM

Gosh EM. You're making me really think here.

The club I'm a member at races scratch-built chassis made out of brass. We have a mixed bag of experienced builders, and newbies. There are some really good builders that make brass torsion chassis. My Rover BRM is still the top car in slow class sportscar with a BWNC1 against an entire field of brass chassis. But the configuration of that rare body as a slot car is incredible. Our rules say the bodies can't be over 57mm widest point. The Rover is 56.5mm wide. If someone were to make a really good torsion chassis under a Rover BRM? I'm done. But that will take time yet.

A well made brass chassis should outperform an aluminum chassis. However. A basic aluminum chassis will outperform a brass chassis that isn't more precise.

For me. It's easier to be precise with aluminum.

Making a brass chassis square is just a bit harder. They say it's all in how you hold your tongue while you solder the parts together.

Fast motors seem to require a more even grip across the rear tires. Fast cars are more of a challenge with a stiff chassis. You need to be very sensitive with weight to keep the rear tires on track. We use urethane tires on a routed, painted track. Traction is not a problem unless the car isn't square.

I hope to make a few brass torsion chassis eventually. Just for fast cars. I like the way aluminum works with slow class cars.

Chris Walker was kind enough to invite me to his home where he gave me some great advice on scratch-building. I'm just basically repeating what he said.

I'm not really a good slot car builder. I'm just a machinist making slot cars out of aluminum. A little good luck didn't hurt along the way.

I hope this answers your question EM?

Thanks very much - yes, your answers are very useful especially the point about different motors and,of course, the greater track and tire width of more modern cars will re-order priorities. Your comment about the size of the Rover sent me searching immediately for its specs but 1963 is a year too new for our pre-1962 class*.

I have entered cars in proxy races where Chris was also a competitor. I don't think you could find a better tutor.

EM

*Division 1 -VINTAGE sports cars (1962 and earlier)
Chassis may be commercially available, or scratch built of brass, wire, plastic, PCB or aluminum.
Maximum 8mm tire max. width measured at contact patch. Entrant must ensure that 8mm max. width is maintained throughout season.
Only rubber or urethane tires allowed in this class- no foam tires. Maximum overall width is 2.25" measured from the outside of the rear tires.
Any manufacturer's motor may be fitted, but must be rated no more than 14.7K RPM. H&R Racing "Jack Rabbit" recommended. Slim-line motors are not permitted.
If a pod chassis is used, the pod screws MUST be tight to eliminate any chassis flex. This will be checked during the pre-race tech.