CarBEN EV5 Full Sized Prototype Construction - 5 Seat Electric Car From Scratch

[2007 ion2]

portal style axles like the hmmvv? low unsprung weight, gear reduction is taken care of by a transfer case at the end of each high angle cv axle, brakes are inboard, which simplifies the suspension some, too, and lets you control what brakes to use more easily.

this lets you have relatively simple and lightweight drivetrain, two motors, two small, light transfer boxes, two axles. no heavy conventional transmission, low unsprung weight, choose the brakes you want/need instead of what you're stuck with. should be easy enough to implement with any modern ifs, everything axles out is able to be easily reused. then, spline the axle into the transfer case "out", on the "in" side, you can key the shaft to accept the appropriate disk, then either mount the caliper to the transfer case, or the body of the car, then have the motor on the end of the "in" shaft.

[2007 ion2]

like this. the green parts (from out to in) are the transfer cases, brake calipers, then the motors.

the nice thing about this design is you can package it however you want, as long as the transfer cases will lubricate. you can have both motors above, in front of, or behind the axles, or one in front of and one behind so they're front and back in the center line of the car.

[samwichse]

Inboard brakes like that are nice for low unsprung weight, but you need a much, much stronger drive shaft to prevent it from being sheared by the brakes. From what I understand, the average max torque a set of brakes can usually do is double the engine output (rule of thumb), and the instantaneous torque can be far higher due to pre-fade and/or stiction conditions.

And that doubled torque is what's coming out after the diff (geared down!).

Plus, I think he's looking for more of a drop-in solution .

Sam

[freebeard]

I can see it (after the 2nd post). The SAAB 900 parts are over-spec for the vehicle, reducing the unsprung weight is a plus, and the brakes can be downsized inboard of the reduction hubs.

[NeilBlanchard]

I've just ordered 1 yard each of a range of s-glass and e-glass fabrics, that I will be making samples to test technique and strength.

http://www.uscomposites.com/cloth.html

Things are moving along slowly, but moving nonetheless.

Who can tell me about how a chopper gun works?

http://www.uscomposites.com/equipment.html

Does it spray glue on the chopped fibers? They don't mention a nozzle or a glue connection.

[3-Wheeler]

Originally Posted by samwichse

... From what I understand, the average max torque a set of brakes can usually do is double the engine output (rule of thumb), and the instantaneous torque can be far higher due to pre-fade and/or stiction conditions......

I think inboard brakes would require even more force than that to stop adequately.

No form of racing that I know of allows in-board brakes:

Formula 1
CanAm
IndyCar
Formula SAE

I would think this option would be *really* hard for a DMV inspector to pass as well. They *always* look for vehicles that have components from other road going vehicles. I spent two years researching this before I stopped production of my tadpole three wheeler.

Jim.

[2007 ion2]

Originally Posted by NeilBlanchard

I've just ordered 1 yard each of a range of s-glass and e-glass fabrics, that I will be making samples to test technique and strength.

Fiberglass Cloth

Things are moving along slowly, but moving nonetheless.

Who can tell me about how a chopper gun works?

Equipment

Does it spray glue on the chopped fibers? They don't mention a nozzle or a glue connection.

the chopper gun chops up fiberglass for odd shape repairs, it's for spots that sheets of fiberglass won't work on. once again, fiberglass doesn't use a "glue", and no, it doesn't spray anything on it, just chops it up for you.

[freebeard]

I think inboard brakes would require even more force than that to stop adequately.

No form of racing that I know of allows in-board brakes:

...snip...
I spent two years researching this before I stopped production of my tadpole three wheeler.

Why? With gear reduction in the hubs you might be able to downsize the brakes. Parking brakes on driveshafts can be tiny (—I hear, about cars that have driveshafts). Here's an example that has a Hayabusa motor chain driven to the differential and inboard disks



Bonneville? Class rules in racing often outlaw things, like powered/active aerodynamics, to keep other cars competitive.

What were the salient points from your research? Looking at the history of racing parts for the air-cooled Beetle, there were basically two types of inboard brakes; one that mounted to the transaxle and one that mounted to the frame horns. So there probably were conclusions drawn, but don't look at me.

[solarguy]

Almost at the bottom of this page is a nice pic of the inboard rear brakes on an xke jaguar. It doesn't take any more force if the rotors are inboard or outboard, but it does mean beefier axles. But he needs relatively beefier axles anyway, because electric motors can produce a lot of torque from a standing start, compared to a gasser of similar horsepower.

index-8

[NeilBlanchard]

I picked an awkward time to order fiberglass - I ordered on July 3rd, and it shipped yesterday and is on it's way. And the day after tomorrow, I will be traveling and I won't be back until early next week.

Also, I'm largely responsible for my kids during their summer vacation, so I'm not getting nearly as much time to work on the CarBEN EV5 chassis as I'd hoped.

I am seriously considering how to approach a crowd funding campaign - a video is required, I think, but a video of what, specifically. How to encapsulate what I've done so far, and how to show the potential of this project. Never mind the little detail of how much money I need to finish this car.

Any and all thoughts you have would be very helpful!