Having seen Alwyn's work on the Chieftain suspension units, I kept looking at my ARRV and thinking that I could retrofit them. There are two issues:
1. I used a KV1 lower hull as it is roughly the same size. This was all done in the days before 3D printers so I took the most robust route.
2. I used Bulldog/Pershing road wheels, and Bulldog tracks, as this was the easiest way to make it all fit and line up.
So, Alwyns units are the right size, but they are designed for the 3D wheels and tyres.
I rejigged the units in Openscad, and designed them to dispense with a few bolts and use stainless rod for hinge points, The back of the units is now flat to fit the KV1 hull.
I haven't printed them yet, and will need fine tuning if I do, I am still working on the JS3, but I with what I have learnt over the years in Openscad I intend returnng to the ARRV at some point to do the suspension, wheels, idler, sprocket, and a shovel that works more like the original. I may even have a go at a fully operating crane but space is really tight for that.
suspension();
suspensionarm();
mirror([1,0,0])suspensionarm();
springmount();
mirror([1,0,0])springmount();
//*****************
module suspension()
{
$fn=100;
difference()
{
union()
{
hull()
{
translate ([-22.5,12.5,25.75])rotate([0,90,0])cylinder(45,5,5);
translate ([-22.5,1.5,25.75])cube([45,11,5]);
translate ([-22.5,1.5,7])cube([45,16,10]);
}
translate ([-13,1.5,-2])cube([26,16,10]);
translate ([-7,17.5,-2])rotate([90,0,0])cylinder(16,6,6);
translate ([7,17.5,-2])rotate ([90,0,0])cylinder(16,6,6);
translate ([-7,18.25,-3])rotate([90,0,0]) cylinder(1,2,2);
translate ([7,18.25,-3])rotate([90,0,0]) cylinder(1,2,2);
translate ([0,18,27])rotate([90,0,0])color("red")cylinder (12,7,7);
translate ([0,23.5,27])rotate([90,0,0])color("red")cylinder( 5.5,4.5,7);
}
translate ([-22.5,18,6.5])rotate([90,0,0])cylinder(20,9.5,9.5);
translate ([22.5,18,6.5])rotate([90,0,0])cylinder(20,9.5,9.5);
translate ([-30,3.5,-14])cube([63,12,30]);
translate ([-7,19,-3])rotate([90,0,0]) cylinder(33,1,1);
translate ([7,19,-3])rotate([90,0,0]) cylinder(33,1,1);
translate ([0,24.5,27])rotate([90,0,0]) cylinder(22,1.5,1.5);//top
}
damper();
mirror([1,0,0])damper();
}
//********************
module damper()
{
$fn=100;
difference()
{
union()
{
hull()
{
translate ([22.5,15,25])rotate([90,0,0])cylinder(10,7,7);
translate ([24,15,30])rotate([90,0,0])cylinder(10,3,3);
}
translate ([25.5,16,26])rotate([90,0,0])cylinder(12,2,2);
}
translate ([22.5,11.25,25])rotate([90,0,0])cylinder(3,17.2,17.2);
}
}
//********************
module suspensionarm()
{
$fn=100;
difference ()
{
union ()
{
hull()
{
translate ([7,15.25,-3]) rotate ([90,0,0]) cylinder(11.5,5,5);
translate ([31,15.25,-3]) rotate ([90,0,0]) cylinder(11.5,5,5);
}
translate ([31,17,-3]) rotate ([90,0,0]) cylinder(13,5,5);
translate ([31,22.5,-3]) rotate ([90,0,0]) cylinder(6,5,5);
hull()
{
translate ([22,13.5,2]) rotate ([90,0,0]) cylinder(8,1.5,1.5);
translate ([23.5,13.5,11]) rotate ([90,0,0]) cylinder(8,1.5,1.5);
translate ([29,13.5,2]) rotate ([90,0,0]) cylinder(8,1.5,1.5);
}
translate ([23,13.5,10]) rotate ([90,0,0]) cylinder(8,2.5,2.5);
}
translate ([7,25.5,-3]) rotate ([90,0,0]) cylinder(40,1.5,1.5);
translate ([31,23.5,-3]) rotate ([90,0,0]) cylinder(40,1.5,1.5);
translate ([23,24.5,10]) rotate ([90,0,0]) cylinder(20,1,1);
translate ([23,11.25,10]) rotate ([90,0,0]) cylinder(3.5,5,5);//cut out
}
}
//************************
module springmount()
{
$fn=100;
difference()
{
union()
{
translate ([23,11,10]) rotate([90,0,0]) cylinder(3,3,3);
translate ([19.25,8,7])cube([4,3,6]);
translate ([18,9.5,10])rotate([0,90,0]) cylinder(2,6,6);
translate ([9,9.5,10])rotate([0,90,0]) cylinder(10,5,5);
}
translate ([23,15,10])rotate([90,0,0]) cylinder(16,1,1);
translate ([7,9.5,10])rotate([0,90,0]) cylinder(10,3.5,3.5);
}
}
