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Re: Other: for ET
By:Etienne Muller
Date: 5/27/2008, 5:53 am
In Response To: Re: Other: for ET (Bill Hamm)

: Hi Et,

: Have a question about the mast supports you made for the tri. Am I correct in
: assuming you used the clamp from a boom for the mast attachment?

: Bill H.

Hi Bill

That is correct. I have loads of old and broken windsurfing stuff lying around and I cobbled the rig fittings together out of that.

The modern mast clamps tend to have very limited up down rotation .You will have to look for a clamp that rotates at least in one direction far enough that you don't have to rake the mast back to 45 degrees. I would put out the word and see what comes up. Broken booms abound. The left over clamps often are OK and of no use to the owners.

The mast supports are actually the tops of carbon masts that I broke in shorebreaks over the years. You will also find lots of these around as two piece masts tend to snap in the middle where they are joined, leaving a perfect lentgh of beautiful light weight carbon tube just right for this purpose.

I have painted the mast supports silver in order to reflect the sun. They heat up fast in their black state.

At the bottom end of the shrouds I used bits of an old windsurfer universal joint.

One thought. Modern windsurf rigs are meant to be sheeted in at all times. They are not really designed for running. When windsurfing they are fully sheeted even when broad reaching, as speeds jump so quickly that the apparent wind is always ahead of the sailor. For this reason, up to date sails are not really that suited to efficient displacement sailing, especially in anything downwind of a broad reach. I mention this because it allows one to apply the mast clamp on the shrouds a little loosely to allow the mast to rotate from one tack to another. The boom clamp above prevents the shroud clamp from riding up the mast. The fact that one tends to be a little over sheeted off the wind helps to stop the clamp from riding down the mast.

Downwind the clamp will want to ride down the mast as it pulls forward. This can be prevented by clamping a ring of some sort below the shroud clamp although I have found that it is not necessary as my sails' boom cutouts are quite small and the mast slieves serve this purpose.

Regarding mast rake. The center of effort in windsurfer sails is quite far forward. They are designed to be fully sheeted in and well raked back when powered up. One of the reasons that this system works so well with the three point base. The mast naturally takes up its optimum rake angle.

I hope this makes some kind of sense.

Et

Messages In This Thread

Other: for ET
Bill Hamm -- 5/23/2008, 11:34 am
Re: Other: for ET
Pat Pierce -- 5/23/2008, 5:51 pm
Re: Other: for ET
Bill Hamm -- 5/23/2008, 6:09 pm
Re: Other: for ET
John Monroe -- 5/24/2008, 3:04 am
Re: Other: for ET *Pic*
Etienne Muller -- 5/25/2008, 7:05 am
Re: Other: for ET *Pic*
John Monroe -- 5/26/2008, 6:22 am
Re: Other: for ET *Pic*
Etienne Muller -- 5/26/2008, 11:07 am
Re: Other: for ET
John Monroe -- 5/27/2008, 4:12 am
Re: Other: for ET
Bill Hamm -- 5/28/2008, 1:37 am
Re: Other: for ET
John Monroe -- 5/28/2008, 4:48 am
Re: Other: for ET
Bill Hamm -- 5/28/2008, 12:02 pm
Re: Other: for ET
Mike Savage -- 5/27/2008, 6:39 am
Re: Other: for ET *LINK* *Pic*
John Monroe -- 5/28/2008, 5:36 am
Re: Other: for ET
Bill Hamm -- 5/28/2008, 12:01 pm
Re: Other: for ET
John Monroe -- 5/29/2008, 4:01 am
Re: Other: for ET
Mike Savage -- 5/28/2008, 9:09 am
Re: Other: for ET
John Monroe -- 5/29/2008, 3:58 am
Re: Other: for ET
Bill Hamm -- 5/27/2008, 1:14 am
Re: Other: for ET
Etienne Muller -- 5/27/2008, 5:53 am
Re: Other: for ET
Bill Hamm -- 5/28/2008, 1:32 am
Re: Other: for ET
Mike Savage -- 5/28/2008, 8:52 am
Re: Other: for ET
Bill Hamm -- 5/24/2008, 12:15 pm
Re: Other: for ET
Bill Hamm -- 5/24/2008, 12:13 pm
Re: Other: for ET
John Monroe -- 5/25/2008, 3:30 am
Re: Other: for ET
Bill Hamm -- 5/26/2008, 1:31 am
Re: Other: for ET
John Monroe -- 5/26/2008, 7:07 am
Re: Other: for ET
Bill Hamm -- 5/26/2008, 1:17 am