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How a cable slide is built and pulls the room

A cable slide never pushes. One set of cables pulls the room out, the opposite set pulls it in, and the weight of the room rides on the sill, not on the cables.

The short version

Pull, never push

Each side of the room has cables at the top and bottom, running from pulleys in the wall opening to standoff brackets on the room's side walls. A cable can only pull, so every cable slide has two opposing sets. As one set takes up cable, the other pays it out.

BAL calls them Out cables and In cables. Out cables anchor to the interior standoffs, at the end of the room that stays inside the coach, and pull those standoffs toward the wall until they touch the wall cap: that's full out. In cables anchor to the exterior standoffs and pull the outside end back to the wall: that's full in.

BAL calls the Accu-Slide a give and take system. At full out the outside (In) cables should have a little play, and at full in the inside (Out) cables should. If both sets are tight at once, the motor is fighting itself.

BAL Accu-Slide: one motor across the top

The motor and gearbox mount on the main wall at the centerline of the opening, above the room, behind an access panel inside the coach. The drive turns a sprocket on each side of the opening. A chain hangs on each sprocket, and both ends of each chain hook to a cable/chain connector. That's four connectors per room, a front and a rear on each side.

Each connector carries a top and a bottom cable on threaded studs with adjustment nuts, locked by 1/4-20 jam nuts, with white foam anti-vibration blocks on the nuts. Eight cables per room. From the connectors the cables run through holes in the wall cap extrusion, around corner pulleys and jamb pulleys, to ball ends held in the standoffs by rubber grommets.

Each connector has a colored tag (red, blue, green or purple) that matches the adjustment sticker BAL ships to go near the slide. One motor drives both sides, so a broken shaft key or a chain off one sprocket lets one side stop while the other keeps pulling.

BAL XACT Slide: a motor in each jamb

BAL's newer XACT Slide with EMFORCE Technology (Forest River files it as Exact-Slide) moves the drive into the side jambs. Each side has its own motor at the top of the mechanism, left-hand R25079 and right-hand R25078, with the chain seated on the motor sprocket between a plastic chain guide and the motor mount. Cables run through jamb pulleys to interior and exterior standoffs as on the Accu-Slide.

The control watches each motor, turns each one off at the end of travel, and learns the motors. So you now have two sides that can drift apart and a control that needs a reset after a motor change. Replacing a motor means pulling the jamb and setting it on the bench.

Lippert F.A.S.T. Track: a column on each side

Lippert's cable system is the F.A.S.T. Track, built in standard and flush floor versions and now listed as obsolete on support.lci1.com. Lippert's own quick ID: the F.A.S.T. Track has a drip tray at the bottom corners of the opening and a lower wipe seal, and the BAL system has neither.

The parts list shows a housing column, a motor on a motor plate, a drive sprocket, #35 roller chain, cable drive blocks with chain connector brackets, steel die springs on 1/4-20 hardware, shielded pulleys, an idler roller, and interior and exterior cable anchor brackets in versions for laminated and stick-and-tin walls. The controller is auto-programmable and has a park brake input harness. Lippert's patent for this design puts a column beside each side of the opening, with the chain loop driving two blocks in opposite directions: one block's cables pull while the other's pay out.

Don't confuse it with Lippert's Above Floor slide. Lippert's Above Floor owner's manual calls that a rack and pinion system. No cables.

What carries the weight

The cables move the room and hold it against the wall at each end of travel. They don't hold it up. The room floor rides on the sill at the bottom of the opening, which the OEM builds as a wear bar, a flush floor pan or a sill. BAL also sells a base roller assembly that replaces a 1/2 in wear bar.

A room dragging on a gouged wear bar or lifting off a roller makes the cables do work they weren't set up for. Before you touch tension, look at what the room rides on and whether it sits on it evenly.

Telling them apart

The label or the paperwork is fastest. If you have neither, two looks settle it: the bottom corners of the opening, and the drive behind the fascia.

BAL Accu-SlideBAL XACT SlideLippert F.A.S.T. Track
Motors per roomOne, top centerTwo, top of each jambColumn drive per side (patent)
AdjustersFour cable/chain connectors, top and bottom screw eachCoupling and jam nuts on chain connectors in the jambCable nuts on the drive blocks with die springs
End of travelRoom seats against the wallControl shuts each motor offAuto-programmable controller
Spot it byColor-tagged connectors over the room, no lower seal or drip trayMotor in each jamb, control with green and red LEDsDrip tray at the bottom corners, lower wipe seal

On the job

  1. Find the label or paperwork: Accu-Slide, XACT or Exact-Slide, or F.A.S.T. Track. If it says Lippert Above Floor, you're on rack and pinion.
  2. Look at the bottom corners of the opening. A drip tray and a lower wipe seal mean Lippert F.A.S.T. Track.
  3. Pull the fascia over the room. One motor at top center is an Accu-Slide. A motor at the top of each jamb is an XACT.
  4. Find the BAL sticker and the color tags on the connectors, and photograph every connector before you touch a nut.
  5. With the room partly out, note which cables are tight (pulling) and which are paying out.
  6. Look under the room at the wear bar or rollers and confirm it rides on them evenly.

Numbers

Shop tip

Before you turn a nut on a cable slide, paint-mark every nut and stud and take a photo of each connector with its color tag. If the adjustment goes sideways you can put it back where it started.

Where this comes from

Try it on a service call

Put the lesson to work on a hands-on troubleshooting case.

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On the job