1. Intolerant Tangs
   Many vessels, especially older ones, have mast tangs that will fit some swages, but are not deep enough to accept other swages, or Sta-lok-type terminals. So you can have perfect-length wire, but rigging you can't install, because the shoulders of the terminals bump into the bottom of the tangs. To fix this, it is often possible to cut some of the bottom of the tang off, assuming that doing so will leave plenty of meat (see "Apprentice" for details on figuring this). If there isn't enough meat, or if the space between the tangs is too narrow, it may be necessary to replace the tangs.

2. Seamless Wiring
   Any competently-wired mast will have a disconnect of some sort, near where the wiring exits the bottom of the mast. Optimally, this is in the form of a bus bar, with all wires color-coded and tagged, and the whole thing accessible without recourse to the more strenuous forms of yoga. But it is a lot cheaper and simpler to run the wiring all the way to the electrical panel, so that is what a few builders do. This is fine, until you have to pull the mast, and then it's a horrid experience of digging into the panel and trying to extricate wires from the tortuous courses they invariably take on the way from the mast. This can be - and therefore usually is - complicated by generously-applied zip ties and screw-on clamps, plus assorted stuck floor panels, plumbing hoses, stowed gear, and wiring that doesn't go to the mast. Fun. So look for a disconnect. If you don't find one, make one. It'll be worth the effort, even if all you ever have to do is replace one wire, without removing the mast.

3. Installing Roller-Furlers
   Near as I can tell, the same people who write computer manuals moonlight on furler system manuals. Some very fuzzy details out there, especially for the first-time fabricator. Some common error opportunities include:

   Insufficient foilage. Here, your luff length is just inches longer than the total foil lengths in a standard package. Be sure to check the maximum standard length, and order an extra, if necessary, for your boat.

   No togglage. Stays with furlers on them sag more than their hank-on cousins, so toggles become extra-important. But it can be tempting to skip them, particularly at the bottom end, due to how many furlers are constructed, and especially if you need to raise the drum to allow anchor clearance. Do it right, or risk fatigue problems.

   Frozen fastenerage. Furlers just about always have stainless fasteners going into aluminum, somewhere, and many people fail to isolate these metals. Tef-gel is our favorite for the job, or Loc-tite, if you need extra security.

4. Exotics and Knots
   Fibers like Spectra and Vectran are dandy when it comes to strength and inelasticity, but many people have discovered, to their loss, that many common knots will weaken exotics by as much as 80%. So don't tie a Bowline in that halyard, splice.

5. Drilling Holes on Masts and Boom
   Many a sure hand with a drill has come to grief when confronted with keeping the bit from wandering on the hard, convex surface of a mast or boom. So make a strong divot with a punch, get a couple of friends to spot you for square, until you get the feel of it, and draw an "X" in pencil through the divot, so you can see if the bit begins to wander. It's hard to move the holes in sail track.

6. Stretch Deductions
   With a new rig, one always deducts a tiny amount (.021% of length, for 1x19 stainless) for constructional stretch. In addition one always deducts a much larger amount for tuning stretch, and this number will vary according to wire length as well as the amount of tension that will come on the wire when tuned. But you only deduct for tuning stretch if your measurements were done in situ, with someone going aloft to measure a properly-tuned rig; all those wires have been stretched in the process of tuning, perhaps by an inch or more, so if you cut the new wires to the measured, the new wires will stretch, and be too long. But if you take the wires off the boat to measure them, they will shrink to their original lengths; if you deduct tuning stretch from these measurements, the resulting wires will be too short.

   That's it for this installment, but you can be sure there'll be another Things That Can Go Wrong (TTCGW) column in the future, owing to the wealth of examples we have on hand. If you have some to contribute, we'd love to see them - maybe you can save some other sailors (or us) from some fresh disasters. Send email to peter@briontoss.com, or use one of the other methods under "Contact Us".

Next Month: Why Double Backstays Are Evil.

   Fair leads,

      Brion Toss