I have an '84 5.7. You do not need a sleeve, no need to remove the base, unless you want to reseal it...the only purpose of the sleeve would be to prevent compression, & deforming the mast extrusion. You are not going to tighten the bolt down that far, in fact the mast rotator will tend to drop down, you will end up attaching a small bungie or line to hold it horizontal.
Visualize what happens during mast rotation. (Hold the mast, then move the rotator arm from side to side) The loads the rotator bolt will place on the extrusion will not try to squeeze the extrusion walls together, they will try to elongate the holes. If can be a powerful force, just try to reduce rotation on a windy day. Mostly the mast will do its own thing just fine on this setup. Downwind you may want to induce more rotation, & on very light conditions you can lock the mast in one spot. That will help prevent the mast banging to/fro & shaking the wind out of the sail, not to mention driving you nuts. It is also very useful when raising/dropping the mainsail if you cannot park your boat directly into the wind. You can pull the mast direct into wind, then cleat, it makes raising the sail much easier. My boat is geared up from my dock, & is rarely ever directly into the wind.
One CAVEAT, if you cleat the rotator, you must remember to uncleat it first, & allow the mast to swing. The manual says you can break the mast if you forget it. I have forgotten if a few times, if you ever tack, then wonder why you are moving so slowly, see if you forgot to uncleat the rotator line. It totally destroys the airflow.
That bolt IIRC is 5/16" SS. Just do it up enough to remove slop from the rotator arm, don't try to crank it down.
This is an early photo & is rigged poorly. I believe Ron (Nacra 55) showed me how to do it correctly. Run it as a continuous line. Start by tying to one padeye(visible just inside the cleats on beam) then through the end of rotator arm, then through cleat, around behind mast, through other cleat, to rotator arm, then finally to other padeye & tie off, or dead end with stop knot. That will give you a 2:1 purchase.
You can see how the rotator hangs down, I added a small piece of line from end of arm up to diamond wire to hold the arm horizontal.
Edited by Edchris177 on May 08, 2012 - 11:08 AM.
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Hobie 18 Magnum
Dart 15
Mystere 6.0XL Sold Was a handful solo
Nacra 5.7
Nacra 5.0
Bombardier Invitation (Now officially DEAD)
Various other Dock cluttering WaterCrap
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