DIY: Replacing Track
Here is a sad truth relating to older boats: the more desirable the piece of equipment you want to install, the harder it is to remove its predecessor. Eyeing the scarred, ugly genoa sheet tracks on our project Norlin 34 plastic classic, I had the feeling I was in for a struggle.
I had long coveted the towable genoa sheet cars that grace so many modern performance cruisers; the ability to adjust headsail sheet leads from the safety of the cockpit is a treat that, once savored, is not easily forsaken. It sure beats kneeling on a lee deck cursing a sticking pin-stop sheet car every time you change your point of sail or roll away some genoa. That’s why so many sailors sacrifice sailing efficiency to convenience and never bother moving their sheet leads at all.
While making the decision to upgrade was easy, choosing what gear to install was not. Harken, Ronstan, Lewmar, Antal, Seldén, Garhauer, Schaefer and Barton all offer variations on the same theme: sheet cars that run on either ball bearings (expensive) or low-friction sliders (not quite so expensive) so that they can be adjusted with a tackle whose tail is led aft to the helm. Ball-bearing cars have the advantage that they can be adjusted under load, and the disadvantage that they won’t fit on your boat’s existing T-track, which will have to be removed and replaced with the manufacturer’s own track. (The exception here is Garhauer, which makes a reasonably priced ball bearing car that it claims will fit on just about any 1in or 11/4in T-track.)
Towable cars equipped with acetal or polyethylene sliders are the budget alternatives. They usually cannot be adjusted under any kind of load, which means you have to ease the headsail enough to depower it before you can pull the car forward. This may not bother you—especially if you sail in a light-airs region—and it is certainly better than wrestling with stubborn pin-stop cars. Slider cars also have the considerable virtue of fitting on your existing sheet tracks, thus saving the expense and the hassle of replacing these.
The battle-scarred T-tracks aboard our Norlin 34 needed replacing in any case, so there was little point in settling for second-best. Each of the various brands of lead car has its attractions, but my choice was dictated by two things: aesthetics (the track and car had to be black) and width, as the track passed so close to a stanchion base that some of the wider cars would have fouled it. In the end, I decided on Harken cars and track. All that remained was to work out the sizes I needed.
Doing the Sums
As with most deck gear, Harken’s track and cars come in several sizes—22mm, 27mm and 32mm, which the company recommends for boats up to 28ft, 34ft and 42ft, respectively. The cost of the components increases considerably with each bump up in size, so naturally, I wanted to see if I could get away with the smaller 27mm Midrange system rather than the 32mm Big Boat stuff for our 34-footer. This depends not on the size of your boat, but on the area of your headsail, which in turn, determines the load exerted on the car and track. As fate would have it, the Norlin carries a big headsail for its length.
For the mathematically inclined, the formula for determining genoa sheet loading is SL=SA x V2 x 0.00431—sheet load equals sail area times wind velocity squared times 0.00431. For the mathematically disinclined, it is much easier to use one of the sheet-load calculators that abound on the Internet, like the one I found on Beth Leonard and Evans Starzinger’s website (thanks, guys). I keyed in the area of my 130 percent genoa—420ft2—and the maximum wind speed in which that sail area would be carried—let’s say I’ve been too lazy to reef and it’s 30 knots. That gave a figure of 1,590lb, well inside the 2,300lb maximum working load (MWL) of Harken’s G273B midrange genoa car. In 40 knots with a 336ft2 sail, equal to a 100 percent jib, the loading is just a tad above MWL at 2,317lb. Dialing the wind speed up to 45 knots and the sail area down to a prudent 200 ft2 gave me a sheet load of 1,746lb.
So that was that—the midrange cars and the R27 track would be the right combo. The original sheet tracks were over 9ft long, to cope with the myriad overlapping genoas and drifters that were in vogue during the early ’70s (along with bellbottoms, mullets and platform shoes). Because I’d ditched the boat’s expansive wardrobe of reaching and running spinnakers, bloopers, reachers and gennakers in favor of a single asymmetrical spinnaker, the track length could be cut from 9ft to a little over 6ft. Two 2m (6ft 6in) lengths of R37 27mm track would suffice.
First, though, I had to remove the existing 11/4in imperial track to replace it with Harken’s metric track—which brings me back to the opening sentence. The sheet tracks on the Norlin had been mounted above a 1/4in aluminum backing plate that was laminated into the deck. Perhaps one in three fasteners came out without too much of a problem; the others, however, had welded themselves to the aluminum over the decades. There was only one solution—an angle grinder and a steady hand…
1 I began while the boat was still under its winter cover. Step One was to establish that the 2m-long new track would be long enough. The lead position for a fully sheeted in genoa was just abaft the stanchion—no problem. Because the track was so short, I decided to have Harken bend it to match the curvature of the originals.
2 The old and the new: the Harken track is narrower than the original 11/4in T-track, but just as strong because of its hollow-extrusion construction.
3 Some of the old fasteners came out very easily….
4 But others did not, because they were stuck fast to the glassed-in aluminum backing plates. I had to cut through the track with an angle grinder and then cut off the bolt heads flush with the deck. Surprisingly, I managed it with minimal damage to the glasswork; it would be covered up by the new tracks in any case.
5 After I plugged the underneath of the old fastener holes, WEST System Six Ten thickened epoxy resin made short work of filling them.
6 I marked the position of the old fasteners with lines and the new holes with crosses, then adjusted the track so as to drill into new fiberglass for the 5/16in fasteners.
7 Easy does it when you’re drilling the new holes. Ideally, you wouldn’t drill using the track as a guide because of the danger of damaging the protective anodizing, but because of the curvature of the track I had to bolt it down as I went and then bend it into position for the next hole. I bedded the track and fasteners with 3M 4200.
8 Underneath the side deck, I used washers and cap nuts on the fastener ends. The glassed-in aluminum backing plate helps distribute the loads.
9 What it’s all about: the ball bearing races under the genoa car minimize the effort required to adjust the car, and the sheaves on the forward track stop allow for a 3:1 purchase on the tackle.
10 Once the holes were drilled and the tracks were bolted down, the remainder of the project went quickly and smoothly. Just as well—I was due a break after the hassle of removing the old tracks. I slid the cars onto the tracks and installed the end stops, then rigged the 3:1 tackle using 15/16in line.
11 I led the tackles’ tails to cam cleats mounted within easy reach of the helm. In winds too strong for adjustment by hand, they can be led to the spinnaker winches. All in all, this was a very satisfying project and has added significantly to my enjoyment of the boat. And isn’t that why we do these things?
GENOA TRIM TIPS: Want to know how to use your sheet leads to make your genoa set well on any point of sail? Click here.
It would be great if replacing T-track were simply a matter of removing the old and bolting on the new; but that would be too easy. It may not surprise you to discover that like just about everything else to do with sailboats, there is nothing logical about T-track, and that 32mm and 1¼in T-track are not the same. European boats come equipped with metric track, while American-built boats were traditionally equipped with imperial or “English” track.
The difference is subtle but important. The fastener holes on metric track are 100mm (1315/16in) apart center-to-center, while U.S. imperial or “English” track is 4in (102mm) center-to-center. If you replace one with the other you’ll have to fill in the old holes and drill new ones. And as if that wasn’t enough, the crossbar of the “T” on 1¼in “English” T-track is 3/16in thick; on metric track, it’s ¼in (6mm) thick. This means that most metric cars and fittings (Harken, Lewmar, Antal, Ronstan, Seldén) will fit on imperial track (Schaefer, Garhauer), but not vice-versa.
Towable ball-bearing cars won’t run on T-track, so if you want to upgrade you’ll have to replace the track too. And, of course, towable cars from one manufacturer can’t be used on another’s track. Lewmar’s sliding-bolt track, which has captive fasteners that can be moved to align with existing holes, is the easiest solution if you’re switching from imperial to metric. But if your boat is already equipped with metric T-track, installing any maker’s new metric track should be fairly straightforward.
Replacing your ancient track and cars with modern alternatives is not a cheap undertaking. The list price for the Harken gear I used was in the region of $1,200, but it is often possible to find good deals online. If you choose instead to retain your existing T-track, an upgrade to towable or even pin-stop cars with low-friction inserts is a whole lot better than nothing.
Photos by Peter Nielsen