An effector: a silicone gun

A project log for RigTig's Big 3D Printer

A DIY 3D printer (big volume, inexpensive, lightweight and portable).

rigtigRigTig 07/09/2017 at 07:090 Comments

The first effector was a 60ml syringe. This is just a bigger version really. I've got a project that needs to print about a meter square, but only 10 to 20 cm thick, and in something a bit softer than ABS and PLA. Lets try silicone. And what does a builder use to apply silicone? A: a silicone gun. So let's try it.

Needed a nozzle about 1.5mm diameter, so I designed and printed one.

use <~/installs/scad/simplethreads.scad>;


module nozzle() {
  difference() {
    union() {
      cylinder(d=23, h=1);
      cylinder(d=19, h=15);
      translate([0,0,15]) cylinder(r1=9, r2=1, h=5);
    thread(3.0, 16.5, 12, 4.0, 0.3, true);
    translate([0,0,13]) cylinder(r1=8, r2=0.75, h=6);
    // hole
    cylinder(d=1.5, h=30);

How stable is a series of layers of silicone? Well, try it by hand and observe the results.

Soft and squishy! And it looks like it'll hold up enough.

OK, now to design a controllable squeezer for the cartridge. Mmm...need something with a bit more torque than the tiny steppers used earlier. Maybe I can try using an R/C motor and an ESC control.