Making Stays / Shrouds for a sailboat mast
There numerous methods for making wire stays for your sailboat. This essay presents a simple method using nicopress ferrule cable clamp fittings which are swaged on using a cheap swaging tool. The toughest part seems to be figuring how how long to make the stays, this essay presents 2 methods.
Method 1 - Measure & Pray
If you are replacing an existing stay on a sail boat, you might have the old one and will know how long it needs to be. Or if you are setting up a new rig, you can use trigonometry or scale drawings to calculate how long your stay needs to be. Make sure to pray a lot while doing your calculations and take into consideration how long your mast & hull connections are like the chain plates and stay adjusters. If you screw up, there are a large variety of variable sized stay adjuster, tangs and stay extenders incase you make one too small.
Mark your wire so that it will be long enough to span the distance, plus go around the timble and back into the ferrules. You can calculate how much extra wire is needed by laying out the ferrules and rolling the thimble along the wire.
Method 2 - Setup & Cut
This is a quick and easy way to make a set of stays. First you need to get a general sense of how long the stay needs to be. Measure the distance from the mast step to the chain plate. Then clamp one end of a measure tape to the mast. Use a 2nd measure tape to get the side distance and presto, you have a good idea how long they are going to be.
Make a set of stays with only one end swaged and attach them to the mast. Setup your mast holding it upright with ropes. The ropes should be tied to the hull much further back than the chain plates so that they won't have as much tension on them. Tie the side ropes to the stern corners if you can, or thru the oar locks.
To hold the wire I use a cable clamp.
Setup your wire on the stay adjusters with their thimbles and ferrules. Use a screw on type cable clamp to hold the wire so you can crimp it. Setup all of the stays this way and take a good look at the rig. Adjust as needed.
I prefer to setup my stays so they are in the 2nd hole down. This allows me to loosen one or the other incase I screwed up and have the mast leaning enough to be noticed. Also it allows for the wire to stretch and gives me room to tighten it down later.
Crimp The Stays
This is a cheap swage-it tool that I purchased, it is just a pair of bars with bolts to create the clamping pressure. The bars have several half moon shapes in them to fit the different sized ferrules.
Here is the finished product, this is the forestay. I like to use quick pins that have a push button. They are kinda expensive so I attach them to the stay adjuster with a little safety wire -- which is crimped the same way the stays are. That way I won't loose them in the drink.