Sliding gate drive rack

How do I choose drive rack for a sliding gate?

Work through the checks in this order:

1. Identify the motor and pinion. Find the operator model and, if possible, the existing rack reference. The operator manual usually states the tooth size of the pinion supplied with the motor. Check the pinion actually fitted if it may have been replaced.
2. Match the tooth size. Mod 4 and Mod 6 teeth are different sizes and will not work together. Do not choose the module from the gate's weight alone. If you cannot establish it, ask us to help.
3. Check the rack you are replacing. Compare its overall size, material, tooth shape, fixing points and, for nylon rack, how the lengths join. The same module does not guarantee that a new length will attach to your existing rack.
4. Work out the length. A useful first estimate is the entrance opening plus roughly 1 m to reach a motor positioned beside it. Check the actual gate travel and make sure the rack will engage the pinion throughout the movement.
5. Check the fixings. Pre-drilled steel rack can use bolt-on or weld-on mounting pieces; moulded nylon rack commonly has lugs for screws or bolts. Other steel rack needs the mounting method specified for that product. Fittings may be included or sold separately, so check the product listing and operator instructions.

What do Mod 4 and Mod 6 mean?

The module describes the size and spacing of the rack teeth. A Mod 4 rack can generally work with a compatible Mod 4 pinion even when the brands differ, but a Mod 6 rack will not work with a Mod 4 pinion. The number does not tell you the rack's length or the weight of gate it can move. If you are adding a length to existing rack, check its shape, fixings and joining ends too; matching teeth do not mean the sections will join.

Should I choose nylon, steel-core nylon or steel rack?

Nylon rack is often quieter and easier to fit or replace than steel rack. Steel may be needed where the chosen nylon rack is not rated for the gate or does not suit the fixing arrangement. Check the limit for the exact product: for example, CAME rates its CGZP Mod 4 nylon/steel-core rack for gates up to 600 kg. That does not mean every nylon rack has the same limit. Whatever material you choose, it must match the motor's pinion.

Replacing part of a nylon run? Use the same rack reference where possible. The joining tabs can differ between makes, so two Mod 4 lengths may fit the pinion but not connect to each other. Steel rack may have pre-drilled holes for bolt-on or weld-on mounting pieces; undrilled rack needs the mounting method specified for that product. Check what fittings are included before ordering.

Can I replace one damaged rack section?

First identify why the section was damaged. Wear, broken teeth, a loose fixing or uneven engagement can point to alignment, pinion, mounting or gate-movement problems that a new section alone will not correct. Do not operate a gate with visibly damaged or insecure drive components.

For a replacement, use the operator, pinion and rack references where possible. Compare the tooth size, rack dimensions, material, fixing positions and the joint with the rack that will stay on the gate. Different brands' Mod 4 teeth may work with the same pinion, yet their nylon joining tabs may not connect. If you cannot find a matching section, ask us about replacing the complete run rather than trying to join incompatible lengths.

How much rack do I need?

For many gates, the entrance width plus roughly 1 m is a useful starting estimate when the motor sits beside the opening. Measure the gate's actual travel and motor position before ordering: the rack must stay engaged with the pinion from fully closed to fully open. Also check the length of each rack piece and whether the price covers one length or a pack.

Building a new tracked sliding gate? Drive rack moves the gate, but it does not support it. You will also need compatible ground track, wheels, guides and stops; see our tracked sliding gate hardware sets to explore the running gear.

Is drive rack the same as sliding gate track?

No. Sliding gate ground track supports the gate's running wheels. Drive rack is fixed to the moving gate and engages the motor pinion; it does not support the gate or establish how much gate weight the hardware can carry. Anti-climb or security spike rack is also different: it is a physical deterrent, not a toothed transmission component.

Do I need rack, chain, a motor or a complete automation kit?

Most sliding gate motors use a toothed rack. Some systems are designed to use a chain instead, including certain hanging sliding doors. Chain will not replace rack on a rack-and-pinion motor: check the operator, sprocket and chain specification before ordering. If you also need a motor, see gate motors and operators. For a new automated gate, compare sliding gate automation kits and check what each kit includes.

Need help identifying a rack or chain?

Email us the operator and rack references, known dimensions and required travel, plus photographs of the teeth and fixings if you can take them safely. We can help identify suitable components from the details you provide. Your installer should check the final fit, alignment and clearances against the manufacturer's instructions and the gate on site.