In progress — following along, not for sale

Turning a longarm quilting machine into one that stitches a digitized pattern on its own.

ThreadRunner is a 2-axis motion-controller retrofit for a Handi Quilter Sweet Sixteen — a from-scratch build documented in the open, machine design through firmware to tablet app.

Follow the build View on GitHub

What it is

A longarm quilting machine moves its head over the quilt by hand or by a stitch regulator; it has no way to follow a digitized pattern on its own. ThreadRunner adds that layer — driving the machine head in X and Y to trace a pattern while the machine's own stitch regulator keeps the needle firing.

📱

Tablet app

Native SwiftUI app for designing and loading patterns, sent to the backend as point and Bezier-curve geometry — no on-device G-code generation.

🖥️

Pi backend

ASP.NET Core service on a Raspberry Pi generates G-code from pattern geometry, streams it with flow control, and tracks job state for pause and resume.

⚙️

Motion control

grblHAL on a Teensy 4.1 board drives closed-loop ClearPath-SD servo motors over a belt-and-screw X-Y frame built for the machine's full working area.

📡

Live feedback

Position and progress stream back to the tablet over SignalR, so the app tracks the stitch path as the machine follows it.

Build status

Design work is well underway; hardware assembly and firmware bring-up are next.

Architecture & design

Motion controller, mechanical drive, and app/backend architecture decided — see the project's ADRs.
Sourcing & fabrication

Bill of materials in progress — frame, motors, controller, and drive hardware being sourced.
Firmware & controller bring-up

grblHAL configuration and motor tuning on the assembled frame.
Tablet app & pattern pipeline

SwiftUI app and Pi backend for pattern design, G-code generation, and job control.