I agree, the best tool is to replace them. Why? Because they can fail catastrophically, without warning. A good friend on his Islander Bahama 24 had his forestay closed body turnbuckle let go in "The Slot" on San Francisco Bay on a windy afternnon, and he was able to save his entire rig by immediately turning downwind - fast action on his part and at least there was sea room. As a result,. the very next week I rerigged our Catalina 25. As the yard worker was removing the single backstay closed body turnbuckle, it literally came apart, right where the hole is! If you value your boat, please, please, please, replace those turnbuckles. What's your entire boat worth to you?
