Mast butt position - moving it

Guest · Post by **Guest** » Sun Mar 18, 2007 8:39 pm

Can the mast butt be moved with the mast in? Obviously the shrouds, backstay and forestay would be very loose, but can it be done? If it can, how would you go about it?

[Posted by: annonymous
]

mkgonz · Post by **mkgonz** » Mon Mar 19, 2007 7:44 pm

Why would you want to do it???

Guest · Post by **Guest** » Tue Mar 20, 2007 4:06 am

According to the sailmaker's recommendations the butt position is too far aft. I'd like to improve the boat's performance.

[Posted by: annonymous
]

mkgonz · Post by **mkgonz** » Tue Mar 20, 2007 7:35 pm

You would like the butt about 1-2 inches from being all the way forward. It will add rake and you can then add pre-bend via rig tension.

chris_z · Post by **chris_z** » Mon May 21, 2007 3:41 pm

We just moved the butt aft about 3/8" and what a difference it makes. Was pretty easy to do, we loosened up the shrouds about a dozen turns, then attached the spinnaker halyard to a line that was tied to a piling at the dock directly front of the boat. We then cranked the spinnaker halyard pulling the top of the mast forward. Once it was under load we found we had to loosen the shrouds another six turns. Then we cranked on the spinnaker halyard again pulling the mast forward. Then, it took about 6-8 kicks with a shod foot at the base of the mast to get the butt to move back by a little under a half inch.

I would assume you would use the same technique to move the butt forward, but this time attach the spin halyard to a piling at the back of the boat.

drosowj · Post by **drosowj** » Tue May 22, 2007 8:40 am

As part of my spring commissioning, I re-tuned the rig and adjusted the butt position - forward. It was fairly easy but somewhat time consuming (3hrs). I began by removing the table, then loosening the shrouds (equally from side to side and recording the adjustment). I then adjusted (lengthened) the forestay to the tuning guide specifications. The forestay is a bit more complicated as the Harken furler is in the way. Then I fit a small 2x4 behind the mast butt track (not against the mast itself). A couple of gentle whacks with a sledgehammer and it slide into position perfectly. (Swing your sledgehammer as if you are trying to sink a 10 foot putt - no harder.) Then I re-tensioned the shrouds and reinstalled the table. Pretty simple, but I'd find a buddy to help you out.