Working with Dyneema is a lot of fun. It makes you feel like Jack Tar working the lines.
The mast head is going to get some new stainless fittings for the back stay so I am waiting on that before we have an exact dimension for the stay. The cap shroud fittings are unchanged so I am starting there.
We are using 5/16ths AmSteel-Blue 12 strand (SK-78) Average Tensile Strength: 13700 lbs,
It is overkill but I didn't want the lines too thin. After calculating what creep to expect, I completed the eyes and we are now tensioning the stay with a come-along between two concrete columns. We discovered the there are 2 types of creep to account for. First is the manufacturers calculations for the weave. For this diameter at 34 feet of length at 20% of breaking strength is .70 %. This is about 3 inches. They second stretch to consider is the looseness you work into the weave with the 2 eyes and general handling. After tensioning up to about 3000 pounds, we pulled about 12 inches of stretch. After that it felt like a piece of rebar.
Another great thing about Dyneema is the fact that you can rework the eyes. We loosened up one eye, shortened the line and re-wove the eye.
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