lts respooler | Applications of randomness

Building a DIY Spool Winder with Repurposed Electronics

I needed a spool winder to transfer filament between spools, so I searched for existing solutions and found the LTS Respooler. Inspired by the V-Spooler design, it offers a more compact form factor while having useful functionality.

My goal was to have a system that could run unattended while evenly distributing filament onto the new spool, and this project checked all the boxes.

While the LTS Respooler is well-designed, well-built, and well-documented, I ran into a major challenge: the required electronics were always out of stock.

Rather than waiting, I decided to adapt the project using components I already had. This meant redesigning the electronics enclosure to fit my available parts and rewriting the Arduino code accordingly.

Components Used

To make it work, I repurposed the following electronics:

Arduino Pro Mini Clone
Nema 17HS5413 1.8’ 1.3A Stepper Motor
DRV8825 Stepper Driver + capacitor
LEDs + resistors
Button
EndStop
4mm sphere
MP1584EN Mini DC-DC Step Down, since the LM2596S I had lying around were quite large and would not fit
connectors and wires

Challenges & Lessons Learned

One of the biggest hurdles was understanding how to properly connect the stepper driver and control the motor using the Arduino. These resources were particularly helpful:

connecting the Arduino Pro Mini to the computer: Instructables Page
understanding the stepper driver: YouTube Video
coding using AccelStepper library: Complete Guide

The AccelStepper library simplified motor control and made fine-tuning much easier. Despite the learning curve, seeing everything come together in the end was incredibly rewarding.