# Gondola preparations

So today we are trying to prepare the main frame to our gondola. The rough idea is sort of like this.

You are seeing rectangular shape formed by CF tubes and corners from 3D printed ABS, while there are clamps to hold three plates. Front for controllers, middle for batteries, which will also serve as balancing the centre of gravity and the rear one for small batteries pack to feed servos.

While constantly working on a good source of tubes, the corner ended up today’s goal. It looks simple but its model evolved through several weeks. Final OpenScad code is below, describing tube-in-tube design from Serge.

```use <ShortCuts.scad>

module corner_tube(simple) {
D(){
union(){
rotate_extrude(convexity = 10, angle=90)
translate([50, 0, 0]) {
D() {
circle(d = 29.5);
circle(d = 25.5);
}
if(!simple) {
square([0.8,26.5], center=true);
square([26.5,0.8], center=true);
Rz(45){
square([0.8,26.5], center=true);
square([26.5,0.8], center=true);
}}}
if (!simple)
for( i = [0 : 2] ){
R(90,0,70/3*i+22)
Tx(50)
cylinder(0.8,13.5,13.5);
}

if (!simple)
rotate_extrude(convexity = 10, angle=90)
translate([50, 0, 0]) {
circle(d = 12);
}}

if (!simple)
rotate_extrude(convexity = 10, angle=90)
translate([50, 0, 0]) {
circle(d = 11.2);
}
}}

module leg_tube(simple) {
D() {
T(35.3,35.3,0)
R(20,20,90){
union() {
tube(0,0,0,29,14.7,14.7,2);
tube_enforce(70, simple);
}
}
rotate_extrude(convexity = 10, angle=92)
Tx(50)
circle(d = 29);
}}

module panel() {
D() {
minkowski() {
D() {
T(2,2,-1)
cube([40,40,1]);
Rz(45)
cube([30,30,80], center = true);
}
sphere(0.5);
}
rotate_extrude(convexity = 10, angle=90)
Tx(50)
circle(d = 29);

//screw hole 1
T(20,8,-5)Rz(45)
minkowski() {
cube([10,0.1,0.1]);
cylinder(10,1,1);
}

//screw hole 2
T(9,20,-5)Rz(45)
minkowski() {
cube([10,0.1,0.1]);
cylinder(10,1,1);
}}

D() {
minkowski() {
R(90,0,-135)
translate([-36,5,-0.5]) linear_extrude(1) {
polygon(points=[[-5,-5],[20,-5],[-11,20]], paths=[[0,1,2]]);
}
sphere(0.5);
}
rotate_extrude(convexity = 10, angle=90)
translate([50, 0, 0]) {
circle(d = 29.5);
}}}

module corner(simple = false) {
corner_tube(simple);

Tx(50)
Ry(45)Rx(90)
tube_enforce(50, simple);

Ty(50)Rx(-45)Ry(-90)
tube_enforce(50, simple);

leg_tube(simple);
panel();
}
corner(true);
```

The idea started quite simple.

Printing seemed to be easy, while taking 15hrs+.

As printing came with few problems (walls collapsing), internal frame needed to be added.

Then went completely crazy, trying to make it lighter with internal super-structure + platform clamp.

Here is the final model which implements the tube-in-tube idea from Serge.

Well, then all printing’s been quite adventurous and took few weeks to tune up.

Then we did a final assembly and it is looking pretty cool!

Added a mock-up platform to show how that will look up when complete.

I am happy with the progress, good to see things moving after a while again!