Making the rig right again

Perhaps your spars have seen better days. A decade or more of seasonal sailing will take its toll on a spar; long-distance bluewater sailing will accelerate the process. You may have noticed the occasional loose fastener, corroded spreader tip or failing paint, all of which are signs that your spar (this encompasses the mast, or masts, and booms) is ready for a thorough overhaul. Whatever the impetus, carefully inspecting and refitting your middle-age or senior spar can pay dividends in the end. A spar refit may offer improved performance, reliability and aesthetics, as well as an opportunity to get to know your rig better.

Refit vs. replacement

There certainly is a threshold at which refitting no longer makes economic sense. At that time, purchasing a new spar may be the best and only logical alternative. Price ranges are wide indeed, and if you intend to replace old with new, ensure that the comparisons are executed by the same measure (a quality cruising rig for a 40-foot vessel may well cost $20,000 to $25,000). Like most manufactured products, options range from economy to deluxe and everything in between. However, if you are handy and intend to do some of the work yourself – especially the grunt work, such as hardware removal and sanding – this threshold may be raised considerably.

This overview will touch on some important areas to consider where matters of the spars are concerned. Entire articles could be penned on several of the topics outlined here.


Once you’ve made the decision to carry out a refit, the extent of it will be determined by the results of your spar inspection. Make no mistake about it; this is not something you can do as well as a rigger with 20 years of experience. There’s no shame in having a pro carry out this inspection. By following these guidelines, however, it will be possible for you to get a sense of your spars’ condition and to what degree they need to be refit.

Begin the inspection with the spars stepped and rigged. This will allow you to check the fit between the heel of the mast and its step, whether it is deck- or keel-stepped. The heel of the mast often lives in a harsh environment. If it’s keel-stepped, it will be located in the bilges, which, depending on the vessel, may be especially wet and salty, setting up an ideal environment for corrosion (the type of decay aluminum suffers in these and many other cases is known as poultice corrosion; its byproduct is a white, gooey material the consistency of something between old, dried-out wheel-bearing grease and wet table salt).

If the spar is deck-stepped, it can live an equally difficult existence, with regular exposure to salt spray as well as rain and exposure to sunshine (heat accelerates the corrosion process). Whether your spar is deck- or keel-stepped, be sure it is equipped with proper drainage or limber holes and that the drains are clear of dirt, debris and salt. If the step is not level and the low end isn’t equipped with a drain, consider adding one. Allowing stagnant water to stand within a mast step or around the base of a mast will only enhance corrosion.

The interface between the heel and the step, the base upon which the heel rests, should be parallel. That is, the mast heel should rest squarely on the mating step, without gaps. Check carefully for cracks, especially in the heel, and corrosion. If the heel corrodes severely, it often will expand and sometimes suffer collapse. While this is dangerous in and of itself – it is often evidenced by seemingly mysterious slackening of the standing rigging – this collapse has the added effect of locking the mast to the step, making the two difficult to separate (I’ve seen smaller vessels nearly picked up off their blocks when a crane attempted to lift a mast whose heel had corroded and collapsed out of its step).

If the rigging shows a tendency to slacken on its own and the mast heel isn’t corroded, check the structure beneath the step. Many builders in the ’60s, ’70s and ’80s used fiberglass-encapsulated wood beneath the step. If the fiberglass fractures over time, or the fasteners that secure the step to this base allow water to reach the wood support, it will rot and eventually be crushed, allowing the step to settle. This rig-settling phenomenon also may occur beneath the compression post of a deck-stepped spar.

Vessels competing in some offshore races may be required to fasten the mast heel to the mast step (to prevent the two from separating in a seaway in the event of a knockdown, capsize or especially tumultuous conditions) using a bolt or long clevis pin. If your vessel is equipped with such a fastening, inspect it for corrosion (to the pin or bolt as well as surrounding mast) and to see that it is still well secured using a cotter pin or nut.

Next, move onto the deck and, for keel-stepped masts, inspect the mast partners carefully. This is the reinforced collar on deck through which the mast passes. To do this properly, you must remove the mast boot, usually a flexible rubber gator that provides watertight integrity between the mast and cabin top (check for watertight integrity; these gators often develop leaks). Between the mast partners and mast are usually wedges or, in some cases, a solid single epoxy-like substance called Spartite. Wedges should be spaced evenly and fit tightly into the gap between the mast wall and the inside of the partners. If the wedges are loose, rotten or crushed, or any of them has fallen into the cabin or overhead, reposition or replace them as necessary.

The final check before unstepping the mast involves the fairlead – a lead that introduces no undue stress – of the stays and shrouds. Pay careful attention to all shroud and stay leads, ensure that none is bound where they attach to the mast or the chain plates, including the stem and backstay fittings. The wire or rod must be parallel to the terminal fitting from which it exits (the end of the wire or rod), be it swage (pressed by machine) or mechanical compression, such as Norseman or Sta-Lok (assembled with hand tools). Additionally, the wire should be parallel to the upper end of the chain plate.

Continue the inspection after the spars have been unstepped. Ideally, you should completely strip the mast of all running and standing rigging. Tag each component of rigging even if you think you are certain of where it fits in the puzzle (if you intend to leave any of these items outside, use weather-resistant Tyvek tags and indelible markers, which are available at most stationery stores). The memory can fade with time, and if the project is carried out during the off-season lay-up, several months may pass before reassembly.

Painted vs. anodized finish

Most spars manufactured within the past 15 years are painted with a two-part polyurethane paint such as Awlgrip or Imron, not unlike that used on hulls and decks. It’s durable, weather resistant and generally looks good for years. In years previous to that, however, many spars were anodized. This process involves subjecting the spars to an acid chemical bath and electrolytic action. The result is a relatively thin but extremely hard coating (the surface hardness is equal to that of a sapphire or ruby). The treatment is a coating of sorts; it adds to the overall thickness of the metal slightly. It also penetrates below the surface, producing a durable protective coating that resists corrosion and oxidation.

Painting aluminum is problematic, so anodizing has certain advantages. Although it’s subjective, most agree that painted spars are more aesthetically appealing than the translucent silver finish provided by anodizing. For maximum corrosion resistance and minimal maintenance, however, there’s little doubt that an anodized finish is superior, and if properly applied, it is designed to last the life of the spar.

This is a juncture in the spar-refit process. If your spars are anodized and the finish is intact, anodizing cannot be repaired. You need do nothing else unless you prefer a painted finish. If the finish is painted and intact, you can move on from here, as well. However, if the finish is painted and it’s in poor condition, showing corrosion and blistering, especially around hardware, then you have a decision to make. In this case, the paint will have to be renewed, but the question is, do you repaint over the old paint, or remove it all and start fresh? If the finish is badly degraded, failing and lifting over more than 40 percent of the surface, it’s probably best to strip it entirely. This may involve long hours and many sheets of sand paper, hanging on the end of a dual-action sander or sandblasting. The latter option is more expensive; however, proper sandblasting leaves an ideal surface for primer and subsequent topcoats. Preparing for sandblasting, however, requires containment of the dust and abrasive media, which may prove costly and time consuming.

Another process that is gaining favor for spar and other paint removal is soda blasting. This is similar to sandblasting. However, it is more environmentally friendly, as the soda eventually dissolves (the paint it removes does not and so it must be disposed of properly). If you take this route, a chemical wash that removes the soda residue from the bare aluminum is required before any primer or other coatings are applied.

Once all the old paint is removed, whether by sanding or blasting, the surface must be chemically cleaned and then primed immediately. Any delay in priming aluminum after it’s been sanded or blasted will allow oxidation, which will jeopardize the adhesion of the coating to be applied.

Because aluminum is difficult to paint properly, you must either be thoroughly familiar with the paint you choose and its application process, or leave this part to an experienced pro. The time-consuming component of this task is the disassembly and prep work and not so much the paint application, so leaving the coating application to a professional may still be cost effective.

The alternative, if the existing paint is only weathered or suffering from limited release and corrosion, is to sand and paint over it. There is some risk of adhesion failure, but a professional painter usually can make that assessment with reasonable certainty (a solvent test will determine if the old coating is compatible with the new coating). This scenario is much less time consuming than wholesale stripping, and it doesn’t require the services of a professional blaster. However, it will not reveal all the flaws, corrosion or existing adhesion failures that may be lurking beneath the paint. It’s a calculated decision that will, once again, be easier with some input from a paint pro.

Whichever paint route you opt for, it will be made or broken by the attention to detail given to hardware replacement. Few single tasks have such an effect on painted metal, particularly aluminum, than reinstalling hardware properly. The reason for this is when metal objects – such as winch bases, pad eyes and cleats – are refastened to a freshly painted surface, the continuity of the coating inevitably is broken. Through this break or wound, water is allowed to travel beneath the paint, which allows the corrosion process to gain a foothold.

I have seen innumerable paint failures – on both new and refit spars and other painted aluminum structures – caused by improper hardware replacement or installation. The solution to this problem is prevention, and it is maddeningly simple: Each and every piece of hardware, every cleat, winch, track, even screws and rivets, must be liberally bedded in a sealant or bedding compound.

It’s worth noting that water is the culprit in aluminum corrosion. It will either enable poultice corrosion to occur (water trapped beneath failing paint prevents aluminum from creating its own tough, natural corrosion-resistant oxide film from forming), or it will act as the electrolyte in a galvanic cell that is set up between dissimilar metals – the aluminum and a stainless fastener, for instance. The bedding process must create a watertight seal between each piece of hardware and the painted surface in order to resolve the paint fracture and resultant corrosion problem. When the hardware is installed, the paint will still be damaged, but the bedding compound will immediately seal the area. This rule holds true for all hardware installations on all painted metallic surfaces, particularly on aluminum and especially on aluminum spars (anodized spars will benefit from this treatment; however, it is not as critical), new or old, including installation of non-load-bearing devices, such as VHF antennas, nav lights and wind instruments.

Once you have made the decision whether or not to paint, continue the inspection process. Look carefully at every weld joint, gusset and fillet (welding creates heat, which will locally weaken otherwise tempered aluminum). If you have decided to strip the old spar of all paint (not applicable to anodized spars), flaws, cracks and damage will be more visible. However, if you are not taking this path, you must be extremely vigilant in searching for incipient damage, especially weld failures and cracks. Corrosion is usually more obvious, although, it often hides beneath seemingly sound painted surfaces. Slight wrinkles or bulges in the paint usually are a sign of corrosion lurking just beneath the surface. Any suspect areas should be probed with an awl or pocket knife before the sanding begins. Painting over such pockets will only lead to future coating failures.

A final note on painting: Older anodized spars that look shabby may be painted with the requisite preparation. Proper sanding or profiling of the surface is as important in this case as it is for other surfaces, be they bare aluminum or painted previously.

Reliable wiring

The best way to ensure nav light, instrument and VHF reliability is to see that every conductor that travels through the mast does so within a dedicated wiring conduit. Wires run outside of conduits, especially on a mast equipped with internal halyards, will have a substantially shortened life because of the increased instance of chafe. Conduits may be added to spars that do not have them, and this is easiest to do during a refit, since the spar is already unstepped and stripped of all electrical components.

In addition to checking for and possibly installing a conduit, it is important to bear in mind that many spars are equipped with wiring that does not meet the recommended 3 percent voltage drop outlined in the American Boat & Yacht Council’s Standards and Technical Information Reports for Small Craft, section E.11. This applies to all nav lights, including those not installed on the mast. In my experience, even many brand-new spars do not meet this standard (it is voluntary, but the visibility requirements for the lights themselves are not). The fact that adherence to this standard determines the range of visibility of your nav lights – especially during times of decreased battery voltage, as often is the case during overnight sailing passages – makes it an important issue.

In addition to determining if your nav lights are wired properly, ensure that they also are aligned properly. I have seen too many nav lights whose red, white and green masthead tricolor light sectors were not shining in the proper arcs. Just what these arcs are, as well as other valuable information, such as under what conditions this light can be used, can be found in U.S. Department of Transportation publication number MI6672.2C, Navigation Rules (a copy of this should be aboard every vessel). Finally, ensure that the proper bulb base configuration and wattage are being used in each fixture. These two details will affect visibility as well as reliability.

No rig inspection would be complete without some mention of spreaders. Take particular note of spreader tips, as these are especially susceptible to poultice corrosion (which occurs when aluminum is constantly wet and starved of oxygen) because of the way spreader boots are installed. It’s difficult to prevent them from retaining moisture. Unfortunately, there’s little that can be done to foil this problem other than to carry out annual inspections, as is the case with spars in general. This requires removal of the boots, drying, cleaning, application of touch-up paint if necessary, and reinstallation.

Spars should be thought of as working machines with many components, and just like most machines, they wear out. A careful inspection and conscientious refit can turn the clock back for most spars, providing renewed reliability, performance and safety.

By Ocean Navigator