How to: Select & Install an Adjustable (not split) Backstay

[Ben G]

I'd like to have an adjustable single backstay for a Mk-II and am leaning toward a 2-block arrangement -- at least I think this is easy/quick-to-adjust and relatively inexpensive. Some of you already have this on your SJ21. Please point me in the right direction with more details as to:
4:1 or 6:1
specific hardware and line size/type
how is your safety cable rigged (close-up photos if available)
recommendations/tips/lessons learned

This boat has a split backstay now, but that along with the raised traveler and other cockpit clutter are detracting from family cruising. I'm starting to develop a plan to re-rig the backstay and mainsheet system, thus any help is appreciated.

[SwampBoogieQueen]

since you already have a split backstay I recommend the following... install a wire rope block Ronstan rf103 at the end of the backstay then attach a 1/8in wire rope with a nicropress eye on each end to one side of the existing attachment points for the split backstay. The length is fairly critical, it should run through the wire rope block with just enough length to allow the mast to go forward no further than what allows the mast to be vertical (to comply with class rules) then attach a purchase system to the other end, this will double the purchase of what ever pulley system you use, so a 4:1 vang type pulley system gives you 8:1 etc. The cleating system has many possibities. My backstay runs into my transom and cleats just inside the companionway. I have heard that the backstay system on White Knuckles is adjustable from four different positions.

The raised traveller does limit your cockpit space. I have used many different traveller systems and I find that I am most happy with the original bridal type mainsheet on my Mark 1. After 25 years of over-rigging literally dozens of boats I have come to the conclusion that simplicity and functionality are not exclusionary.

Willie Blevins

[Ben G]

Willie, your solution fits very nicely with what I had hoped to end up with. It's great to get the benefit of your experience. You have saved me hours of research and perhaps avoided a less optimal retrofit. Many thanks!

As to your philosophy on over-rigging, I claim little rigging experience, but feel we are kindred spirits. I'd wondered "why not" install the original bridal system and appreciate your encouragement in that regard.

Another question is whether to use a headknocker to cleat the main sheet. I'm thinking this would clear the cockpit floor and possibly allow the cleat to be positioned at more than one place on the boom -- depending on whether I needed to be class compliant or preferred a more forward position to facilitate single-handed sailing.

[SwampBoogieQueen]

Some people like the head knocker rig, one of my San Juans has one. I prefer the fixed position of the mainsheet cleat for racing and that is most if not all of what I do. I have found the headknocker to be inconvenient for easing the main quickly in heavier air, but in truth it is much more about what you get used to and your personal preference than one system being superior to another.

No substitute for time at the tiller...

[Capt. Woogy]

Ben, Here is a shot of the mainsheet bridle and head-knocker system used on both Blue Pearl and Kermit, two of the top boats out west. It's way too simple yet does what you want it to, center the boom when fully sheeted. Plus it totally clears up the cockpit. I used this set-up last weekend for a regatta, however rather than a head knocker mine runs to a block on the cockpit floor. Like Willie thats what I'm used to. You know, I don't think I missed fussing with the traveller at all, just turn that stick at the back and go.
- Chris

[bluepearl]

Ben, Here is a shot of the mainsheet bridle and head-knocker system used on both Blue Pearl and Kermit, two of the top boats out west. It's way too simple yet does what you want it to, center the boom when fully sheeted. Plus it totally clears up the cockpit. I used this set-up last weekend for a regatta, however rather than a head knocker mine runs to a block on the cockpit floor. Like Willie thats what I'm used to. You know, I don't think I missed fussing with the traveller at all, just turn that stick at the back and go.
- Chris

Sweet, that boat looks fast! I'm pretty sure that crew is an Olympic hopeful too

[Ben G]

Now THAT"S a clear cockpit! However, to rig my boat with either that headknocker on the boom or stand-up block/cleat on the floor, I would not know the specific parts to order. The headknocker in the photo appears to a "single block with cam cleat" but what's the sheave diam? Part# would be even better. Same for the block at the end of the boom. I'm just getting started and need to learn some basics. Also, before making a purchase decision, I do need some "tiller time".

However, my mainsheet is currently controlled by a floor block/cleat with a few ailments:
1. It's mounted on a DIY fabricated aluminum pedestal with structural issues -- it's "bendy" and with a few more flexes will likely fatigue and fail. At a minimum, I've got to scrap the pedestal and mount the block/cleat (with standup base) to the floor prior to going back out on the water. This may mean new holes in the cockpit floor, or perhaps a block of wood can serve as a makeshift pedastal. Ideas?
2. Also when the mainsheet is tensioned, the 3" harken hexa-ratchet block is pulled ontothe cam cleat, such that the sheave rotation grates on the cleat. Not sure what to do about that -- perhaps remove the wedge under the cam cleat--need a cheap fix for the interim, until a final solution is identified. Thoughts?
3. I also need to determine what blocks are needed for the original bridal system, prior to removing the traveler. Help?