Another design assistance request.

[Roxy]

Did you ever get your Auto Bed Leveling going? Is this distracting you from making progress on that?

[LambdaFF]

Hi EMU,
The soft I use has a feature called "multi section surface generator" where you specify a curve profile, then place several sections along the profile and let it generate the necessary NURBS in between. See sketch below of what it would do here.
I would handle the wheel covers separately. In fact I would design half and do a XZ plane simmetry afterwards.
If you tell me the rough dimensions you have in mind, I can look into it one of those evenings.

edit : it might make it easier to print the 2 halves separately.

EMU.jpg

[bford903]

What about something like this? A Ford Model T.

58921.jpg


Cut off the back end and shorten the front end a little. Might be a good place to start to get the basic shape. Lots of good photographs of the Model T from just about every angle.

[old man emu]

I can't thank you enough for doing this for me. It is amazing to see that the files have been downloaded 8 times (as at 0:0Hrs UTC 28/12/14)

The car was a frequent element in the newspaper cartoons of Emile Mercier, published in Sydney, Austrlia in the 1950s and 60s. Emile was born in French Polynesia, so there is a connection to the Tri-color. http://en.wikipedia.org/wiki/Emile_Mercier_(cartoonist) Apart from being topical at the time of publication, his cartoons record the Common Man in Sydney in the 1950s before massive intakes of European migrants changed the culture, and as such form a useful historical record.

The car was probably created in response to the many micro-cars that were produced just after World War ll. The make of the car was never given, but a favorite letter group that Mercier used was "ETAOIN". I think I'll use that because there are cartoons depicting the "Shrldu Special", 'shrldu' being another of his letter groups (see Wiki entry for an explanation of these letter groups).

The car had a number of variations, mainly around the front of the engine and the tyres. In this cartoon,

Profs car.jpg

the car is being driven by the character "Argylle. There doesn't see to be a name for his lovely passenger.

Here is another model:

front.jpg
which show some design changes.

These types: gravypie rhs.jpg Profs car quarter view.jpg show how the car was depicted in the background of many cartoons.

At one time in the early 1960s, a full-sized car was made and a novelty item and driven around the site of an international trade exhibition in Sydney.

What I would dearly like to do is make a good print of the car and visit Emile's grave and place the car on it.

Old Man Emu

[old man emu]

First, congratulations to your wife and you. Your son must be the best Christmas gift you have ever received.

I have only read your post quickly as I have other work to do around the house, but I think I understand now what you did. A small problem I'm having deciphering your diagrams is that they are labelled in French. Are your axes labelled differently? If so can you complete this?

X =
Y =
Z =

OME

[LambdaFF]

First, congratulations to your wife and you. Your son must be the best Christmas gift you have ever received.

I have only read your post quickly as I have other work to do around the house, but I think I understand now what you did. A small problem I'm having deciphering your diagrams is that they are labelled in French. Are your axes labelled differently? If so can you complete this?

X =
Y =
Z =

OME

Hi EMU, no in fact all those sections are designed in 2D, so it says H and V, stands for Horizontal and Vertical.

[old man emu]

The Model T front end would be OK. However, it's not that part that is giving me difficulty. It's the bodywork. The closest thing I know of that it is like is an egg chair, like this:

Replica-Arne-Jacobsen-Egg-Chair.jpg

That is pretty close to the shape I want, and I can draw that in 2D. Just turn this picture upside down and do some cutting.

I need to be able to produce a plan view. I'll play with it later today.

OME

[Mjolinor]

It looks like a Hansom Cab with a caster on the back.

[Roxy]

If you load this into Open_Scad, it approximates the shape you are looking for... In order to actually use it, you would need to add more points to better define the shape. The red circles are there so you can see how the cut_out() is formed and to make it easier to play with. Adding the # symbols to the side_profile() module might be helpful to get its shape closer to what you want.

After the side profile is defined, a large block of that shape is made at [10,0,0].

side_profile();

difference() {
translate([10,0,0]) hull() { 
    side_profile();
    translate([0,0,5]) side_profile();
}
translate([10,0,0]) hull() { 
    translate([0,0,-.1]) cut_out();
    translate([0,0,5.1]) cut_out();
}

}



module side_profile() {
difference() {
    main_body();
    cut_out();
}
}

module main_body() {
hull() {
    translate([0,1,0]) cylinder(r=1, h=.1, $fn=30);
    translate([1,0,0]) cylinder(r=.25, h=.1, $fn=30);
    translate([2,.5,0]) cylinder(r=.5, h=.1, $fn=30);
    translate([3,1.5,0]) cylinder(r=.5, h=.1, $fn=30);
    translate([3.25,2.5,0]) cylinder(r=.5, h=.1, $fn=30);

    translate([3.5,3.5,0]) cylinder(r=.25, h=.1, $fn=30);
    translate([3.0,4.25,0]) cylinder(r=.5, h=.1, $fn=30);
    translate([1.75,4.7,0]) cylinder(r=.5, h=.1, $fn=30);
    translate([1.5,4.5,0]) cylinder(r=.25, h=.1, $fn=30);
}
}

module cut_out() {
hull() {
#    translate([-1,2.75,-0.01]) cylinder(r=.5, h=.2, $fn=30);
#    translate([1.,2.15,-0.01]) cylinder(r=.35, h=.2, $fn=30);
#    translate([1,3,-0.01]) cylinder(r=.25, h=.2, $fn=30);
#    translate([.75,4.25,-0.01]) cylinder(r=.25, h=.2, $fn=30);
}
}

But probably, it might make sense to make the shape nice and smooth by starting with a couple of spheres and scaling different dimensions and then putting a hull() around that? Do the work with 3D objects instead of doing a 2D object and making it 3D ????

[old man emu]

This is as far as I have gone. I cannot figure out how to create the curved sections that will allow me to make the solid. I'm using Rhino 5.


So far so good.jpg

QUESTION: When I finally make this shape solid, how thick should the solid be? I was thinking 2mm.

OME