Measuring Up

This weekend we tackled the next step on the rigging checklist- measure it! The standing rigging consists of various wires which hold up the mast- in our case 8 in total- the port and starboard upper shrouds, fore and aft starboard lowers, fore and aft port lowers, headstay, and backstay.

At both ends of each wire is a contrivance called an “end fitting” which terminates the wire in a solid thimble. The length of the wire is measured from the centerline of the hole in the thimble- which is where a solid pin called a “clevis pin” lives which allows the wire to be attached to either the mast at the top or a turnbuckle at the bottom.

Obviously an accurate measurement is important- when the time comes to put the mast back in the boat it will be expensive, not to mention embarrassing, if something doesn’t fit. So we fiddled around with a few different ways of getting the wire stretched out and settled on this:

Tensioning the wire with ratchet straps worked great on the forestay and backstay, but the hook was too large to attach to the shrouds. We found we could get it plenty tight by hand and driving a nail to hold it in place- keep it simple stupid.

 Does that look right?

I had a moment of paranoia when we began to measure the shrouds- if the starboard and port shrouds were of significantly different lengths it would imply some sort of major structural deformity. Apparently it’s common for boats to be a bit asymmetric, but one never knows right? Fortunately our measurements for all four shrouds agreed within 1/16″.


So we stretched out the wires, I would take two measurements, and Ryan would record the data. We used the boatbuilder’s method of recording offsets feet-inches-eighths. So our measurement of 31-4-6+ for the forestay equates to 31 feet, 4 inches, 6/8″ plus a 16th or 31ft 4 inches and 13/16ths.  It sounds complicated but it’s much easier to call out 14, 5, 3! then 14 ft 5 inches and 3/8ths! Which, incidentally is the length of the port aft lower shroud. You got that?!

Having measured everything up and taken a close look at all the rig components, I’m glad we decided to replace everything. The wire itself is in good condition- no signs of corrosion. The turnbuckles however are pretty rough, primarily because the rig was installed without any toggles. Toggles are fittings which allow the wire to shift fore and aft or athwartships, and thus ensure a “fair lead” from the attachment point on the hull to the attachment point on the mast. The forces the rig creates conspired to bend several turnbuckles over time as a result of a “foul lead.” Now we have to design the new rig, but more on that later. That enough nautical arcana for ya? Thanks for reading!

PS- Still waiting on an accurate prediction for the as-yet-unannounced name, any guesses?


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