5.9mm Sub-Micro Slip Ring Product Guide

Product Guide: 5.9mm Sub-Micro Slip Ring with Adapters


This guide describes how to use the Brickstuff 5.9mm Sub-Micro Slip Ring with Adapters kit.

For as long as we've offered our Ferris Wheel lighting kit for sale, people have asked: how do you have the power on the outside while the wheel rotates without tangling the wires?  The answer: a cool little device called a slip ring, which allows electrical connections to be maintained during rotation.  We spent years scouring the planet to find the smallest, most compact slip ring available: with an outer diameter of just 5.9mm, you can fit it just about anywhere.

This kit includes everything you need to route two separate power circuits through 360 degrees of motion.  The included adapter boards separate the two inputs/outputs so you don't need to do any soldering to connect everything, and the green power LED indicator lights on each adapter show you when power is turned on to each circuit.

Here are the specifications for the slip ring included in this kit:

In the illustration above, the "rotor wire" side of the ring is considered the "front side" in this document.  The "stator wire" is considered the "back side" in this document.

You can also tell the "front side" of the ring by its shorter wires.  The "front side" has wires that are approximately 4 inches (10cm) long, while the "back side" has wires that are approximately 16 inches (40cm) long.

The slip ring is supplied inserted into a 1x4 LEGO® Technic brick, but if you don't need to use it this way (or if you need to use it in a non-LEGO® model), you can carefully remove the slip ring from the brick by pressing from the back side (the side with the longer wires) with a non-sharp object.

Be careful when removing the slip ring-- your ring may fit tightly into the LEGO® Technic brick.  If you are not able to press it out gently using your finger, then apply light pressure from the back side using something that is not sharp.  NEVER PULL the ring out by its wires-- doing so can cause the ring to come apart, slip out of its metal shell, or can cause the wires to break.  We cannot be responsible for damage done to slip rings by pulling on wires, and damaged rings cannot be repaired.


To use this kit, mount the ring in the CENTER of rotation for the model you are working on.

For proper operation and to avoid damage, it is critical that the ring be in the CENTER of rotation, and also that the ring be able to move FREELY while rotating.  It is also important to make sure the wires on both ends of the ring do not get caught or pulled as part of the rotating motion.

When determining how to mount the ring, the most important consideration is that the ring itself must not carry any weight of the model.  You need to find a way to fully support the model and the weight of its objects rotating without putting any pressure on the ring itself.

As an example, below are two illustrations showing the ring mounted horizontally through the center of a rotating LEGO® part.  Note that the weight of the model is supported by the two blue pins, NOT by the slip ring itself.  The red shaft rotates freely and the model is supported by the surrounding parts.  No weight or pressure is applied to the ring itself.

For proper operation of your ring, it is critical that you find an arrangement like the one above, where any weight of the rotating part(s) is carried by the frame of the model, not the slip ring.

Sometimes, a vertical mounting is better than a horizontal one.  Here is another example, also from a LEGO® model, that uses a vertical rotation arrangement where 100% of the weight of both rotating elements is supported by a LEGO® turntable piece (top and bottom halves that snap together and rotate).  The slip ring fits through the hole in the center of the turntable, free to rotate without carrying any of the weight of the model.

Spend enough time planning the installation and orientation of your slip ring before mounting.  Finding a creative solution that removes any weight from the ring itself will ensure your lights continue working for many years without damage to the ring or the wires.


Once you have mounted your slip ring, you can connect the adapters on both ends of the slip ring's wires.

It does not matter which wire end you connect either board to-- both boards are identical and connections on both ends of the slip ring are electrically identical.

Both adapters have labeling and indicator LED lights for the two electrical circuits: OUT1 and OUT2.  The illustration below shows one example of how two Brickstuff buttons could be used to control lights on two independent circuits through the slip ring.

If you were using the slip ring inside of a carnival ride model, for example, Circuit #1 could represent the color-changing lights around the perimeter of the rotating part of the ride, and Circuit #2 could represent the white lights inside the rotating part.  Splitting these lights into two circuits would allow you to set brightness and effects independently from outside the model itself.


Thank you for purchasing this Brickstuff product!  Your support means a lot to our small, family business, and it allows us to wake up every day and continue doing the work we love: making really cool things to take your models to the next level!

If you have any questions or problems with this product, please send us an e-mail and let us know how we can help.  You can also comment directly about this guide below.

If you make something really cool with this product, please share on social media and tag us (@brickstuff on most platforms) so we can see your awesome work!