The New Hotness

Ortur YRC-1: Petite Chuck Jaws

The standard jaws for the Ortur Rotary loom over small-diameter workpieces:

Ortur Rotary Focus Pad - home offset adjustment — Ortur Rotary Focus Pad – home offset adjustment

Some measuring and modeling produced petite 3D printed jaws:

Ortur Rotary - printed jaws — Ortur Rotary – printed jaws

Admittedly, those jaws aren’t doing much of anything, but they’re not nearly as much in the way. You (well, I) can screw them in closer to the center to overlap the chuck jaws or another hole outward for slightly larger cylinders.

The solid model looks about the same:

Ortur Rotary Jaws - 2-3 show view — Ortur Rotary Jaws – 2-3 show view

They build face-down with a little support under the screw recesses for a clean fit on the chuck:

Ortur Rotary Jaws - Prusaslicer — Ortur Rotary Jaws – Prusaslicer

Teeny jaws might be handy:

Ortur Rotary Jaws - 2-2 show view — Ortur Rotary Jaws – 2-2 show view

Screwing them in one hole outward lets them grip medium cylinders without sticking out from the chuck jaws:

Ortur Rotary - small printed jaws — Ortur Rotary – small printed jaws

The OpenSCAD code lets you pick which screw holes you want, but it does not error-check the perverse choices.

The OpenSCAD source code as a GitHub Gist:

	// Ortur Rotary Focus Pad
	// Ed Nisley – KE4ZNU
	// 2026-01-04

	include <BOSL2/std.scad>

	Style = "Show"; // [Build,Show,Chuck,ChuckJaw,Jaw]

	InnerScrew = 1; // [0:3]
	OuterScrew = 3; // [2:4]

	/* [Hidden] */


	ID = 0;
	OD = 1;
	LENGTH = 2;

	HoleWindage = 0.2;
	Protrusion = 0.1;

	Gap = 5.0;

	NumSides = 834;
	$fn=NumSides;

	WallThick = 2.0;

	ScrewHead = [4.0 + HoleWindage,7.0 + HoleWindage,4.0];

	ChuckOD = 66.0;
	ChuckThick = 10.0;

	ChuckBCR = [3.5,7.5,15.0,22.5,30.0]; // M4 tapped in chuck jaws
	ChuckJawOA = [ChuckOD/2,8.0 + HoleWindage,3.5];

	JawBlock = [0,15.0,2*WallThick + ScrewHead[LENGTH]]; // .x will be variable
	JawRound = 1.0; // tip rounding

	//—–
	// Single chuck jaw with holes

	module ChuckJaw(Holes=true) {

	difference() {
	intersection() {
	cuboid(ChuckJawOA,anchor=BOTTOM+LEFT);
	cyl(ChuckJawOA.z,d=ChuckOD,anchor=BOTTOM);
	linear_extrude(h=ChuckJawOA.z)
	hexagon(od=ChuckOD,rounding=2.0,anchor=LEFT);
	}
	if (Holes)
	for (i = [0:len(ChuckBCR)-1])
	right(ChuckBCR[i])
	down(Protrusion)
	cyl(2*ChuckJawOA.z,d=ScrewHead[ID],anchor=BOTTOM);
	}
	}

	// Chuck layout

	module Chuck(Holes=true) {

	cyl(ChuckThick,d=ChuckOD,anchor=TOP) position(TOP)
	for (a = [0:120:360])
	zrot(a)
	ChuckJaw(Holes);
	}

	// Gripping jaw

	module Jaw(Screws=[1,3]) {

	HoleOC = ChuckBCR[Screws[1]] – ChuckBCR[Screws[0]];
	JawOAL = HoleOC + ScrewHead[OD] + 2*WallThick + (JawBlock.y/2)/cos(30);

	difference() {
	left(JawOAL/2)
	intersection() {
	cuboid(JawBlock + [JawOAL,0,0],anchor=BOTTOM+LEFT);
	linear_extrude(h=JawBlock.z)
	hexagon(od=ChuckOD,rounding=JawRound,anchor=LEFT);
	right(JawOAL)
	linear_extrude(h=JawBlock.z)
	hexagon(od=ChuckOD,rounding=JawRound,anchor=RIGHT);
	}
	right(0*JawOAL/2)
	for (i=[-1,1])
	right(i*HoleOC/2) {
	down(Protrusion)
	cyl(JawBlock.z,d=ScrewHead[ID],anchor=BOTTOM);
	up(2*WallThick)
	cyl(JawBlock.z,d=ScrewHead[OD],anchor=BOTTOM);
	}
	down(Protrusion)
	cuboid([JawOAL,ChuckJawOA.y,WallThick + Protrusion],anchor=BOTTOM);
	}


	}

	//—–
	// Build things

	if (Style == "Chuck") {
	Chuck();
	}

	if (Style == "Show") {
	xrot(180)
	yrot(90) {
	color("Gray",0.8)
	Chuck();
	up(ChuckJawOA.z – WallThick)
	for (a = [0:120:360])
	zrot(a)
	right((ChuckBCR[InnerScrew] + ChuckBCR[OuterScrew])/2)
	Jaw(Screws=[InnerScrew,OuterScrew]);
	}
	}

	if (Style == "ChuckJaw")
	ChuckJaw();

	if (Style == "Jaw") {
	Jaw(Screws=[InnerScrew,OuterScrew]);
	}

	if (Style == "Build")
	for (j=[-1:1])
	fwd(j*(JawBlock.y + Gap))
	up(JawBlock.z) xrot(180)
	Jaw(Screws=[InnerScrew,OuterScrew]);

view raw Ortur Rotary Jaws.scad hosted with ❤ by GitHub

2026-01-09