CarBEN Model -- 1/24th scale model and 3D computer model for EV

[RobertSmalls]

Originally Posted by Bicycle Bob

I hope you have some idea of the time and expense involved in making a car from scratch, to a standard that other people would ride in it. Homebuilt aircraft are much simpler, on average, and usually have plans and other support available. 10% of them are completed by the first builder, 10% by the second, and 10% by the third, with 70% being scrapped before use. Most cars have more man-years just in design work than you have available in your whole life. There are a few exceptionally talented builders; have you been astounding people with your other projects? Energetically, custom cars only pay off if they have features that get copied in production cars.

I hate to say, Bob is right. It would be vastly simpler, cheaper, faster, and the result would be much better, if you use a donor chassis. This is especially true if you want the car to be smooth and stable at highway speeds. An interior that other people will want to sit in is another challenge for the DIYer. As for safety, I wouldn't trust myself to design crumple zones or seat belt attachment points, let alone ABS and airbags.

I say, find a compact car whose handling and interior you like. Then buy one that was in a rollover, sell the interior, and attach your body over its.

[NeilBlanchard]

Hi,

I've added wheels, and contoured the bottom somewhat:




The wheels are 27mm diameter, which is 25.5", and they are ~9" wide in the tread. I bought them at the slotcar track I frequent -- hence the white letter sidewalls...

[RobertSmalls]

I love the rear wheel fairings. The approach and departure angles look plausible, too.

You need to murder out those tires, son. Daytona don't make no LRR's.

The back still looks very large to me. Can you get away with more aggressive angles, a narrower rear track, rear outrigger suspension (my favorite option!), or a boattail?

[luvit]

c;mon... buy some smokes and blow on it. or you know.

[NeilBlanchard]

The rear is ~4'-6" wide, and virtually the same from the ground to the "peak". My biggest mistake so far is the bottom of the rear should not curve up -- it should be straight back, and have a crisp corner, like the sides and top.

I can't narrow the back unless it extended farther back, and the top slope is already limiting the usable headroom. I'm going to try to draw it and see how I can arrange the seats, etc.

BTW, I'm thinking that the front wheel skirts are articulated by connecting them to the steering rods. The wheels will be able to move a small amount without moving the skirts, but at low speeds, which is the only time you steer up to the lock, the skirts kick out as required. The bottom could be a truncated circle, that rotates with the skirt.

[moonmonkey]

race car builders build cars from scratch, and some people do it fast, but these cars are very much unrefined as mentined and expensive if you dont know how to do it, you should make freinds with a racecar fabricator to at least pick his brains, getting a donor car as suggested sounds like the best idea, but it needs to be a full frame car,( not a unibody) so that leaves out a whole bunch of cars, i wanted to do a complete body mod on my echo but when you go cutting on a unibody with all those crumple zones and cad designed stress points you could easily weaken the wrong thing, great looking design though.

[NeilBlanchard]

Here's an update -- I've started drawings of the CarBEN concept EV:



Next, I need to fit the major components into it ... and start to work out the structural ideas.

FYI: drawing foreshortened curved surfaces is not easy, and I've fudged things a little. The dotted arcs around each of the front wheels on the bottom view are the pivoting sections, that move along with the outer skirts, when the wheels are turned sharply.

I'm going to check the angles to make sure that they "comply" with known limitations. The wheels are ~25" outer diameter, so, the rims are 15" diameter. The rear wheel track is ~8" narrower than the front wheel track. The wheels are dashed when they are hidden within the bodywork.

The bottom slopes up towards the back (also shown dashed behind the wheels strakes). The sides are more convex than my model is, and the wheels are closer to the sides than they are in the model, as well. This makes the strakes more asymmetrical.

[user removed]

Something like this for a donor car would get you a long way with little effort. Also an antique which woud mean (at least in VA) you would not have to deal with much regulatory issues or inspections.

Saab : eBay Motors (item 290395979898 end time Feb-05-10 14:38:28 PST)

I have a 71 Karmann Ghia that I was thinking about messing with, but I kind of lost interest, until I can get something going on my IVT.

regards
Mech

[RobertSmalls]

Originally Posted by NeilBlanchard

Here's an update -- I've started drawings of the CarBEN concept EV:

Neat. What did you draw it in?

[NeilBlanchard]

Hi Robert,

Originally Posted by RobertSmalls

Neat. What did you draw it in?

I used DataCAD X3 -- I use it normally for architectural drawing.