Adjustable backstay?

[Dick Westwood]

I sail a Cal 20. This off season's project: replace the standing rigging. It's been suggested that I add an adjustable backstay (fixed backstay currently). For background: she has a fractional rig - the headstay connects at 22' up a 26' mast (an 85% rig?) I've added some basic controls (vang, cunningham, outhaul). It's not practical to rig a traveller.My questions are alarmingly dumb and basic!Should I go ahead with an adjustable backstay? What benefit am I going to get? Any suggestions regarding 6:1, 8;1, 12;1 etc.?When and how do I trim the adjustable once I'm using it? How do I tell when the tension's enough, too much, etc.? (Subtopic - how do I avoid bending the mast in two!)Don - I have the book and charts, but feel I need more info on this aspect of trim.

 

[Jim11228]

cal 20

ask these guys: http://www.cal20.com

 

[Alan]

A frac rig will definitely benefit from an adjustable backstay, especially one that has a jumper strut on the mast like yours.The backstay is tensioned to flatten the main which de-powers it as the winds increase minimizing heel and weather helm.If you check with the guys who race these boats you will get good advice as to how to rig a backstay adjuster.

 

[Don Guillette]

Mast bend or mast rake

Dick: thank you for buying my book and chart. I hope you have enjoyed them.The first question you or anyone who is about to make a sail trim adjustment is - what am I trying to accomplish when I push or pull any given sail trim control. If you can actually bend your mast, which I don't think you can do, to make it look like a J boat mast - point your index finger straight up and then bend it. If your mast will look like that when you crank on the backstay then you've got something. If you refer to the QUICK REFERENCE I included with your SAIL TRIM CHART you'll notice that bending the mast adjusts draft depth. What you are doing when you bend the mast is exactly what Alan stated - you are flattening the sail by taking the belly out of the middle of the sail.On the other hand, if all the backstay adjuster is able to do is RAKE the mast aft, I would not bother with an adjuster. Like everything in life too much can be a bad thing. If you rake that mast beyond 5 degrees or so the boat will slow down and actually not point very well.Do you think you can bend your mast? I don't know as I've never sailed a Cal20. If you can bend it I'd go with the adjuster and I'd see what other guys are using. I'll bet 6:1 or 8:1 would be adequate.