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Some more together.Working on the rear hood now.

If you wanted to keep it simple then you should have used a two link trailing arm suspension with coil over shocks and a De Dion rear suspension component or a track rod setup to help locate the side-to-side reactions of the suspension. See this for some ideas and a PDF. https://www.theengineerspost.com/types- ... on-system/
What I see is not simple. Simple would have been a CAD drawing of a tube chassis and an FE analysis to guide you on how to make the best design that will create great torsional and bending resistance with a minimum of tubes. That fiberglass body will not add much to any torsional resistance so it has to be created in the chassis. You could have used the VW chassis and cut off the rear torsion tubes, designed a tube box for the rear suspension and to hold the engine and transaxle.
There have been other mid-engine versions that could have given you inspiration and kept it simple.

I think it would be a lot of work on CAD but then I haven't worked on CAD since the mid 90s.

The cage alone I would think should be designed differently for load transfer that the body and probably the frame would have a hard time doing. It is the twisting that can be done both by the suspension and the torque plus other things that can happen.

CAD has changed a lot since the 5 different versions of it I used back in the late 70s and into the 90s were in use and I am sure they are still upgrading constantly based on what I understand.

Lee

Suspension was designed by Volkswagen. It is old school but I am pretty sure they had more engineering design power than I alone do.
The tube chassis was bought as a mid engine beetle off road unwelded kit. I never built the beetle. I cut the height down of the kit and made the body mount perimeter myself as this was a non pan , flat floor board kit .
It does look a lot different this short. Chassis is extremely rigid, might not be if the car weighed 2000lbs more. The plastic body is not a structural member.

And yes I have cad and use it daily, but close to retirement age.

DeathBySnuSnu wrote: ↑Sun Feb 11, 2024 6:39 pm Suspension was designed by Volkswagen. It is old school but I am pretty sure they had more engineering design power than I alone do.
The tube chassis was bought as a mid engine beetle off road unwelded kit. I never built the beetle. I cut the height down of the kit and made the body mount perimeter myself as this was a non pan , flat floor board kit .
It does look a lot different this short. Chassis is extremely rigid, might not be if the car weighed 2000lbs more. The plastic body is not a structural member.

And yes I have cad and use it daily, but close to retirement age.

You or CAD! When I retired, they were working on getting CAD to work on multi (I forget how just how many angles) angle milling/machining things.

Lee

It would be interesting to see what the "pan"/frame does look like.

Both

Acad Fusion is supposed to take over, it does solids in 3d and can compile the g code for multi axis machining.
I do use it, have two modern 3d machines. The vast majority of machines and g code compilers still work in flats, so the majority of my work is in 2d. Draw parts in 2d cad then import into the machine specific compiler and create the g code.

Pics of the tube chassis are a page back.

The car is on the road.... sort of.
It is finished but I had another stroke and have been sidelined for a while.
I drives and corners well, I have not been to it's limits.
The only problem is being short stiff suspension and a rigid chassis. I have gotten it in common frame twist situations and gotten a wheel of the ground.

Take care man , and let us hear it when your back at it.

Sweet!