Brass chassis explanation.

[irco]

Gone Racing

What I learned from the build was:

1. It's no use lightening the chassis too much by using lighter materials (e.g. PCB or for that matter aluminum, plastic card or popcicle sticks) if the CG ends up too high.

2. It's better to use heavier materials (brass wire or plate, steel wire or plate) where strength is needed but as low as possible to keep CG low.

3. A rough calculation holds if the chassis does not slide:
Lateral G force at tipping = weight of car x half width / height of CG

If you do this check it is amazing how much effect low CG and car width have. Once it slides this no longer holds true.

4. Some twisting flexibility also seems to improve the handling.

Regards

irco

[Gone Racin]

Hi irco
Good points.
Flexibility is one of the areas of chassis design that has seen intensive development. The right amount of flex in the right places makes for big improvements in handling. That begs the question how much is the right amount, unfortunately there is no simple answer, it depends on factors such as how the rest of the car is designed and how much grip is available.

[rixvette]

For you Aston Martin fans, my resin DBR1 is ready. Check the 'Jerseywallz' thread.

[Mike-]

Gone Racin, irco -

The flexability requirement of the chassis is...from my experience, mostly dependant on two things -
1. The track design. E.g., banked turns (degree and diameter).
2. Tire type, overall traction.

Now this, as you say also somewhat/sorta depends on keeping the motor low, keeping the body weight low and low (physically low).

I've got several spring steel chassis and a bunch of plastic chassied cars. The odd thing is...the plastic chassied cars seem to prefer to be stiff. No loose pod, no loose body to chassis..!
BUT, my steel chassied cars, the more flexable the better.
All the same track, same track power.
My steel chassied cars have Falcon, JK, x12, INT15, G20 and two with (big buck..) Euro motors in them.
The looser (more flexable)..the better it seems with these. And a couple are really flexable and in many directions.

While I have a coupla 1/24 cars, the above info is all 1/32 cars. My 1/24 cars are wing cars with various motors and a Euro chassied car with a 12 strap can motor. These are all pretty flexable. The Euro chassied car (older) has movement in several locations that's pretty interesting. All are fairly fast.

Mike

[slotdream]

Googles

Good evening Google's looking at your work has inspired me to learn this fine art,would be so kind to inform my on what jig to purchase the cobra chassis is outstanding and I am collecting the cobra style cars from that era and would love to build my own chassis, if you still have the blue print for that chassis may I please study it thanks in advance marc. Email is trakmaster1027@gmail.com .god bless