S/V Johanna Rose: Replacing the Head Stay

Why I Replaced It

This project started when I found small pieces of what appeared to be a Delrin bushing on the foredeck of Johanna Rose. After some investigation, I discovered that one of the Delrin liners in the Schaefer roller-furling system was deteriorating.

I contacted Schaefer Marine about obtaining a replacement liner. I didn't know exactly which furler model was installed on the boat, but with their help and a few measurements, I identified it as the older Schaefer System 2000.

The System 1100 and System 2000 use the same foil extrusion, so one way to distinguish between them is by measuring the furling drum. The 1100 drum measures approximately 3.125 inches across the top, while the System 2000 drum measures approximately 3.49 inches.

To replace the Delrin liner, the entire headstay and furling assembly had to come down so that the foil cap could be removed.

Mistake #1 — Planning to Reuse the Existing Headstay

My original plan was to disassemble the existing Sta-Lok terminal, remove the foil cap, replace the deteriorated liner, and then reinstall everything using a new Sta-Lok wedge and former.

After getting into the project, however, I reconsidered that approach. I didn't know the age of the existing headstay wire, and since the entire assembly was already down, this seemed like the ideal time to replace the wire rather than reinstall an old and potentially aging headstay.

I therefore cut off the old Sta-Lok terminal and pulled the old wire out of the furling foil.

And that led directly to...

Mistake #2 — Pulling Out the Old Wire

I later learned that the normal procedure when replacing the wire inside a furling foil is to use the old headstay as a messenger for the new one. The end of the new wire is securely joined to the old wire, and as the old stay is pulled out, it draws the new stay through the foil behind it.

There's a good reason for doing this. Many furling systems have inserts at the joints between foil sections with only a small central opening for the headstay wire. Once the old wire has been removed, feeding a new 5/16-inch wire through all of those openings can be extremely difficult or impossible.

At this point, I thought I might have created a much larger project for myself. The apparent solution was to drill out all of the foil rivets, separate the foil sections, install the new wire through the inserts one section at a time, and then rivet the entire assembly back together.

Fortunately, before doing that, I called Schaefer Marine to order replacement rivets.

That phone call saved me a lot of work.

The Schaefer representative explained that the System 2000 uses foil inserts with a radial U-shaped groove rather than a small hole through the center. This makes it possible to install a new stay even after the old wire has been completely removed.

The procedure was simple: feed the new wire through the foil until it reaches an insert, then rotate the foil slightly until the wire finds the opening of the U-shaped groove. Once aligned, the wire slides through to the next section.

I followed Schaefer's instructions, and they worked perfectly. The new 5/16-inch headstay wire fed through the entire foil assembly without having to drill out a single rivet or disassemble the foil sections.

What initially looked like a potentially major mistake turned out to be a relatively easy problem to solve—and I was very happy to avoid taking the entire furler apart.

Parts Purchased for the Headstay Replacement

51 ft of 5/16-inch 1×19 T316 stainless-steel wire
- KOS WIR-SSW-1X19-10F
5/8-inch threaded turnbuckle with toggle for 5/16-inch wire
- Sta-Lok STAUB23588
5/16-inch swageless terminal
- Sta-Lok STA21108
5/8-inch clevis pins
- Sta-Lok STA05710PKT2
1/2-inch clevis pins
- Sta-Lok STA05708PKT2

In the end, what began as a project to replace a deteriorating Delrin liner became a complete headstay replacement. With the furler already removed and the age of the existing stay unknown, replacing the wire and terminal hardware provided some additional peace of mind and avoided having to take everything apart again later.

The biggest lesson from the project: if you're replacing the headstay wire in a roller-furling foil, don't pull the old wire out until you know how the foil is constructed. Whenever possible, use the old stay as a messenger for the new one.