Maintaining standing rigging
Routine inspections and prompt maintenance should keep the mast where it's supposed to be-up
Modern standing rigging needs remarkably little maintenance. The days of slushing the mast are long gone, but there are things to pay attention to and a bit of preventative maintenance to be concerned about.
The first thing to take a look at is to see that the rig actually fits your boat. An obvious point is length: Are the wires the correct length? Are the turnbuckles roughly centered up, such that the wire is not so short that the turnbuckle just engages, nor so long that the turnbuckle is totally cranked tight? A more subtle point is to check that the clevis pins match the wire terminals, mast tangs and chainplates. An undersized pin may look OK, but it presents a weak spot in your rig. A properly sized clevis pin is designed to spread the load it carries around the entire pin and what it interfaces to. A pin that is too small will point load and cause the mating surfaces to go oval.
The next thing to check is the condition of the wire and terminals. Stainless steel wire and terminals are remarkably durable but they do not last forever. Stainless steel work hardens as it ages, it become more and more brittle, and corrosion is also an enemy. It is important to thoroughly check the wire and terminals at least once a season. Wire typically fails with strands breaking right at the swage. A close examination and luck can catch this as it is breaking, but it is far more likely to see an actual broken strand. Terminals will fail a few different ways, and a classic problem is the swage cracking. But threaded terminals can also fail right at the threads. Terminals on the lower end of the wire typically fail more quickly due the proximity to saltwater and the fact that they are wet more often.
Three types of inspections
There are essentially three forms of rig inspection: a quick look at the rig with everything in sailing form, loosening things up and inspecting each terminal and pulling the mast to inspect each component intensively. You should take a quick look several times a year, a more in-depth look at least once a year, and you really should pull the stick to make sure everything is in order every four to five years. Of course, if you store seasonally with your mast down the schedule changes a bit.
A great way to inspect rigging is with a handheld microscope. You can get an inexpensive microscope from Radio Shack; model 63-1313 is less than $20 and provides up to 100x magnification. Optically inspecting with a microscope is more practical and less expensive that dye testing or other methods.
Assuming the wire all looks good, you'll need to take a look at the chainplates and mast tangs. Again you are looking for any cracking or corrosion. Chainplates will often fail at or below the deckline, as trapped moisture can cause the hidden stainless steel to succumb to crevice corrosion. Be sure to examine the mast tangs and especially the through-bolts. Wire halyards have been known to saw right through mast through-bolts over time.
Tune it up
A rig will last much longer, and your boat will sail better, if it is properly tuned. A rig should not be too tight or too loose. A rig that is too tight puts additional static stretch on the wire and everything it is attached to. A rig that is too loose will shock load on every tack as the rig slams from tack to tack. A dramatically over-tightened rig can actually permanently damage the wire, which can stretch beyond its elastic recovery point and fail catastrophically.
As I said, standing rigging doesn't last forever, and ideally it should be replaced before it fails. The lifetime of a rig is variable: it depends on the state of tune, the climate, water salinity and more. Worst case, a boat sailed hard in tropical conditions may need a new rig every five to seven years. A lightly sailed boat in fresh water can stretch this lifespan considerably, and 15 or more years is not unreasonable.
A large portion of your rig is held together with cotter pins. They secure the clevis pins and hold the position of your turnbuckles. You may be tempted to replace your cotter pins with circular pins, sometimes called cotter rings or ring dings. These seem like a good idea, with no sharp edges and the fact that you can install and remove them without tools, but they are not secure. An errant sheet can snag a cotter ring and easily pull it out, if the ring is in a clevis pin the result could be devastating. A better solution is to use traditional cotter pins. You'll need to tape them to prevent sail and sheet damage, but they will stay put until you take them out.
Speaking of tape, rigging tape or white electrical tape does the job, but you can get better tape at a better price at your local Home Depot. 3M Linerless Rubber Splicing Tape does a great job as rigging tape, yes it is black, but think of it as industrial chic. It is thicker, lasts longer and just plain works better. Best of all, a 30-foot roll is less than $15.
Maintain the turnbuckles
A part of your rig that does need true maintenance is the turnbuckles. Turnbuckles should be cleaned and lubricated periodically, and the procedure varies depending on what the turnbuckles are made of. Turnbuckle bodies are typically made of stainless steel or chrome-plated bronze. Usually traditional style open-body turnbuckles are bronze while the closed-body designs are stainless steel. The cleaning procedure is the same on both: just loosen the turnbuckle all the way and wipe the threads down with a rag dampened with mineral spirits.
Lubrication of turnbuckles is a little more complicated. Stainless steel and bronze work well together, so with a plated turnbuckle you only need to reduce friction. In this case the turnbuckle should be lubricated with a dry lube such as McLube's Sailkote or any Teflon-based lubricant. In an all-stainless turnbuckle you need to be careful to avoid galling. Galling is a form of cold welding, where the metals actually fuse together on a molecular level, and it occurs when stainless parts interface without proper lubrication, it can cause turnbuckles threads to tear or in severe cases for the turnbuckle to seize up. You can avoid galling by lubricating the threads periodically. I have successfully used automotive anti-seize compound and Tef-Gel works well too. Use the lubricants sparingly, and you'll need to just be careful to not get the lube on sails and running rigging while in use. An even better solution, if possible, is to swap out the stainless steel body for a plated bronze version.
You don't want to worry about your rig, and with a little attention your rig will last for many years. If you neglect things you could be facing a dramatic rig failure. The choice is fairly simple.