DIY endless tow: a one-motor shuttle for foil and skim

A DIY endless tow is a rope loop that never runs out. One motor on the shore turns the loop, a carrier on the loop pulls the rider across the water, and reversing the motor brings them back. No boat, no driver, and no walking the rope back out between rides.

Prototype, not a product. Nothing here is for sale, and nothing has carried a rider yet. This is a home build, not a certified tow system. Build and ride at your own risk.

What is an endless shuttle?

System 6.9 is one endless rope loop strung between two low A-frames on a shoreline. On the drive shore, a motor turns a capstan drum. The rope wraps the drum several times, and that grip moves the whole loop. On the far shore there's only an idler pulley on a sliding carriage, with springs that keep the loop tight. Nothing on the far shore needs power.

It's meant for foil and skim, at a tow height of about 0.8 to 1.5 m over a span of roughly 80 to 150 m. The rider goes one way, the motor reverses, and the rider comes back on the same loop.

What a site needs

These are the site conditions the guide is written for. If your shoreline is very different, read the build guide before you buy parts.

• Length of water

  The build is meant for a span of roughly 80 to 150 m, at a tow height of about 0.8 to 1.5 m, for foil and skim.

• Anchor points

  Two low A-frames on the shoreline: a drive frame for the motor and capstan, and a far-shore frame for the idler pulley and the springs that keep the loop tight.

• Power

  Only the drive shore needs power for the motor and battery. The far shore is just a pulley, with no power run across the water.

• Local rules or permission

  Check the rules for your lake, and get permission before you put anchors or a motor on the shoreline.

Endless loop vs other DIY tows

• One-way beach winch

  How it works: a spool reels the rider in on one long rope. Then someone walks the rope back out before the next ride.

  Trade-off: the simplest machine to build, but every ride ends with a long walk, and the rope on the spool changes the pull as it winds up.

• Two winches, one at each end

  How it works: each winch pulls in one direction, so the rider goes back and forth. A FOIL.zone thread discusses this setup.

  Trade-off: no walking, but you build, power and control two machines, one on each shore, and they have to work together.

• One-motor endless loop (System 6.9)

  How it works: one motor and a capstan on the drive shore move a closed loop. Reversing the motor reverses the rider.

  Trade-off: one machine and one power source, and the far shore is just a pulley. The work is in keeping the loop tight and making the drive end safe, which is what the guide's test ladder is for.

• Two-tower cable

  How it works: commercial back-and-forth systems run a cable between two tall towers, with the rider towed from above.

  Trade-off: a professional installation with its own site requirements. System 6.9 is a low, DIY shoreline build, not a replacement for one.

Safety comes first

Every build in the guide starts with a mushroom E-stop wired to a contactor that cuts the battery, a soft ramp of 6 to 12 seconds on every start, stop and reversal, guards on every chain, belt and nip point, and a spotter on the E-stop for every ride. Nothing goes to the lake until the bench grip test passes, and nobody rides until the loop has run empty in both directions.

How to build one

• Read the build guide

  The free build guide covers how it works, the build order and test ladder, the drive-end housing and the line and loop length.

• Understand the parts

  Parts, explained walks through the capstan, bearings, motor, controller, battery, E-stop, rope, fairleads, A-frames and tensioning, and what to look for in each.

• See other builds

  Builds shows what other people have made and how to share yours. Related DIY tows collects wake winches, FOIL.zone winch threads and foil tow boogies.

Not a certified tow system. You build it, you're responsible for it.