Build your Motorised Camera Slider (Slide + Pan)

This is the build that turns phone clips into cinematic shots. Your camera glides smoothly along an aluminium rail and turns at the same time, and it repeats the move exactly, every take. It's our most involved kit: some mechanical fitting, a few connectors, and a little set-up on a computer. Take it slowly, follow the steps in order, and you'll finish with a properly useful studio tool. Plan on an unhurried weekend for the DIY kit.

Which version do you have? - DIY kit: follow every step. - Assembled: the rail, carriage, slide belt, pan head and electronics are built and GRBL is already set up. Do Step 9 (join the pan carriage and plug in the motors), then go to Control software and Calibrate the pan. - Fully built: go straight to Control software. Your slider is already calibrated, and your settings are printed on the quick-start card.

3D render of the printed parts (not a photo).

What's in the box

| Item | Qty | |---|---| | Printed parts: roller carriage, belt carriage, pan-motor carriage, pan bearing mount, tensioner, two end caps, board mount, tripod mount, pan head, camera plate | 11 | | 2040 V-slot aluminium rail, 500 mm | 1 | | V-slot wheel kits | 3 | | NEMA 17 stepper motors with 1 m cables | 2 | | Uno-compatible board, CNC Shield V3, A4988 drivers | 1 + 1 + 2 | | GT2 20-tooth pulleys (5 mm bore), GT2 idler (3 mm bore), 608 bearings | 2 + 1 + 4 | | GT2 open belt (2 m) and one 260 mm belt loop | 1 + 1 | | 12 V 5 A power adapter, USB A-B cable | 1 + 1 | | 1/4"-20 camera screw, M5 × 30 screws and nuts, M3 screws, nuts and T-nuts | set |

Tools you'll need

• Hex keys: 2, 2.5 and 4 mm (M3 and M5 screws)
• Small Phillips screwdriver and a small flat screwdriver (driver trim pots)
• 8 mm spanner or pliers (M5 nuts)
• Side cutters and a pair of scissors (belt)
• A multimeter (to set driver current and check motor coil pairs)
• A Windows, macOS or Linux computer with a USB port
• Optional: a soldering iron. It helps seat stubborn M3 nuts in their pockets.

Safety notes

• Never plug or unplug a motor while the 12 V adapter is on. It can destroy the A4988 driver instantly. Always unplug the adapter first.
• Driver chips and motors get warm in use. That's normal, but don't cover the drivers. Keep the heatsinks on.
• Fit the A4988 drivers the right way round (see Step 7). A reversed driver burns out the moment you power up.
• Moving belts and pulleys can pinch fingers and hair. Keep clear while a move is running.
• Clamp or tripod-mount the slider before you load a camera. Start every new move with a light load, then add the camera.
• The 12 V adapter is mains powered. Use it indoors, keep it dry, and unplug it when you're done.

Step-by-step build

The original designer, Adam of Adamslab, has a build video that shows each part being fitted. Watching it alongside these steps helps a lot: <https://www.youtube.com/watch?v=6d8_oJsUrao>

1. Prepare the printed parts

Check every part for loose strings and clean the holes. The M3 nut pockets are made slightly undersized on purpose so the nuts stay put. Press each nut in firmly with the flat of a screwdriver. If one refuses, warm it gently with a soldering-iron tip and let it sink into place. The M3 and M5 holes are made slightly oversized. If a screw is tight, run a matching drill bit through the hole by hand.

2. Build the roller carriage

Assemble the three V-slot wheels: two bearings and the spacer go into each wheel. Fix them to the roller carriage with the M5 × 30 screws and M5 nuts. Two wheels go on one side and one on the arm. Fit the M3 × 30 tension screw into the slot on the arm. You'll use it in Step 4 to squeeze the wheels onto the rail.

3. Fit the end caps and motor

• Bolt the slide motor to the motor end cap with M3 screws and push a 5 mm-bore GT2 pulley onto its shaft. Leave the grub screws loose for now.
• Fit the 3 mm idler pulley into the idler end cap with an M3 screw and nut.
• Drop the M3 T-nuts into the rail slots. Slide the carriage onto the rail, wheels in the V-grooves, before you fit the second end cap. Then bolt both end caps to the rail ends.

4. Adjust the wheels

Tighten the M3 × 30 tension screw on the carriage arm a little at a time. The goal: the carriage rolls freely along the whole rail, with no wobble when you twist it by hand. Too tight and it will stutter; too loose and your footage will shake.

5. Run the slide belt

Cut about 1,050 mm from the 2 m belt. Clamp one end in the belt carriage, then run the belt around the motor pulley, along the rail, around the idler and back to the belt carriage. Pull it snug and clamp the other end. Fix the belt carriage to the roller carriage with M3 × 10 screws into the nut pockets. Line the pulley up with the belt and tighten its grub screws onto the flat of the motor shaft. A good tension is a low "thum" when you pluck the belt, with no visible sag.

6. Build the pan head

• Fit the second motor to the pan-motor carriage and add the second pulley.
• Fit the 608 bearings into the pan bearing mount. They guide the 260 mm belt loop. Fit the pan head and run the loop around the motor pulley and the pan head.
• Take up the slack with the tensioner until the head turns with no backlash.
• Screw the camera plate to the pan head and fit the 1/4" camera screw.

7. Electronics

1. Press the CNC Shield onto the Uno. Every pin must line up, with none left hanging.
2. Under the X and Y driver sockets, fit three jumpers under each socket (M0, M1, M2). This sets 1/16 microstepping, which gives the smoothest motion.
3. Plug the A4988 drivers into the X and Y sockets. Match the driver's EN pin to the EN marking on the shield; the small trim pot usually ends up nearest the 12 V terminal side. Fit the heatsinks.
4. Screw the board stack into the board mount, then fit the mount onto the rail.

8. Set the driver current (important)

With the motors unplugged, connect the 12 V adapter and USB. Put the multimeter's black probe on GND and touch the red probe to the metal top of each driver's trim pot. Turn the pot gently until you read about 0.6 V. That's a cool-running, quiet setting with plenty of force for phones and light cameras. For a heavier camera you can go up to about 0.8 V. Unplug the power again before going on.

9. Connect the motors

Join the pan carriage to the roller carriage. Plug the slide motor into the X header and the pan motor into the Y header. Route the pan motor's cable so it can follow the carriage along the whole rail without snagging. A cable tie to the carriage helps.

Wiring

| From | To | |---|---| | 12 V adapter + | CNC Shield 12V + screw terminal | | 12 V adapter − | CNC Shield 12V − (GND) screw terminal | | Slide motor (4 wires) | X motor header (2B 2A 1A 1B) | | Pan motor (4 wires) | Y motor header (2B 2A 1A 1B) | | Uno USB-B | Your computer |

Check the polarity of the 12 V terminal twice before powering up. A vector copy of the diagram is in docs/wiring.svg.

Firmware flashing (GRBL 1.1)

The slider runs GRBL, the free, open-source motion controller used in thousands of hobby CNC machines. Source and releases: <https://github.com/gnea/grbl>

1. Install the Arduino IDE from arduino.cc.
2. Download GRBL from the releases page and unzip it. Inside, you'll find a folder named grbl.
3. In the Arduino IDE, choose Sketch → Include Library → Add .ZIP Library… and select that inner grbl folder. Zip it first if the IDE asks for a .zip.
4. Open File → Examples → grbl → grblUpload.
5. Pick Tools → Board → Arduino Uno and the right port, then click Upload. The IDE warns about low memory. That's expected for GRBL and perfectly fine.

Kits marked "Assembled" or "Fully built" already have GRBL installed.

Control software

1. Install Universal G-code Sender (UGS). It's free from <https://winder.github.io/ugs_website/>. Any GRBL sender will work.
2. Connect at 115200 baud. You should see Grbl 1.1h ['$' for help].
3. Open docs/grbl/grbl-settings.txt and send each $ line in the console. GRBL remembers them permanently.
4. Use the jog buttons. X slides the carriage, Y pans the head.

Calibrate the pan

The slide is already exact: 80 steps per mm. The pan depends on how the belt loop meets the head, so measure it once:

1. Put a strip of tape on the pan head as a pointer and type G91 G1 Y360 F200.
2. If the head turns more or less than one full turn, work out the new value: new $101 = 80 × 360 ÷ degrees it actually turned. For example, if it turned 400°, $101 = 72.
3. Send $101=<new value>, then repeat until 360 gives exactly one turn. From then on, Y is in degrees.

Testing

1. Slide the carriage by hand to the motor end, power on and send G92 X0 Y0.
2. Jog X by +10 mm and measure. It should move exactly 10 mm. If it moves the wrong way, set $3=1. For the pan, add 2 ($3=3 reverses both).
3. Run docs/grbl/example-moves.gcode with no camera fitted, then again with your camera.
4. Watch the first full-length run. The carriage must not reach the end caps. Max travel is about 380 mm on the 500 mm rail.

Troubleshooting

| What you see | What to do | |---|---| | Motor buzzes or shakes but doesn't turn | Coil pairs are mixed up. Find the two wires with a low resistance between them and make sure they sit together (2B-2A, then 1A-1B). | | Motor misses steps or the carriage stalls | Raise Vref a little (0.7–0.8 V), lower $120 acceleration, or check the wheels aren't over-tightened. | | Footage shows small jerks | Check that all three microstep jumpers are fitted, the belt is tight, and the pulley grub screws are on the shaft flat. | | Driver very hot | Lower Vref. Make sure the heatsink is on and there's air around the board. | | Board not found on USB | Try another cable or port. CH340-based boards may need the CH340 driver on older Windows/macOS versions. | | "ALARM" in the sender | Send $X to unlock. Homing and limits are off in our settings, so alarms usually mean a reset mid-move. | | Pan head slips | Tighten the tensioner, and check the belt loop teeth sit fully on the pulley. |

Make it yours

A longer rail gives more travel; set $130 to match. Ask us about a tilt (third) axis, Wi-Fi control, heavier-duty motors for DSLRs, or pre-programmed time-lapse routines.

Credits

• Mechanical design: OpenSlider XYZ by Adamslab (Adam's Laboratory), <https://github.com/Adamslab/OpenSlider>, licensed GPL-3.0. We use the printed parts unmodified. In line with the designer's own notes, our electronics use his documented low-cost alternative: an Uno with a CNC shield, A4988 drivers and GRBL.
• Firmware: GRBL 1.1 by Sungeun K. Jeon, Simen Svale Skogsrud and contributors, <https://github.com/gnea/grbl>, GPL-3.0.
• Guide, settings file, example moves, wiring diagram and renders: MyPartLab. They are shared under GPL-3.0 to match the source.