Backstay or NO backstay, that is the question

[dakman50]

I currently have a sloop rig SC26, with a backstay.

I would like a large main which would include a longer boom and full roach main. I would like to remove the backstay and replace it with a pair, on each side, of baby stays. I don't see much changing in the loading on the mast or am I missing something?

Any insight to this change would be most helpful.... Thanks!

Dak

[BOATMIK]

Howdy,

It is easy enough to design a backstayless rig in the size you are talking about.

The most simple way if starting from a blank sheet of paper is to simply move the shrouds back so they are around 25deg back from equal with the mast and set up the spreaders correctly.

But with existing boats it can be a bit of a problem changing internal structure to take the loads of the changed rigging. There may not be any structure inside the boat at the right place with the right sort of strength to attach chainplates to.

This is a backstayless 24ft keelboat - it originally had a bigger rig and a backstay to hold it up - it has been sailed in much stronger winds than the ones at the time of the photos.

http://members.ozemail.com.au/~storerm/Orangeboat/orangeboat2working.jpg

We had the opportunity to put the internal structure where we wanted it when we undertook a big lightweighting campaign.

Michael Storer

[dakman50]

Michael,

Looks like you've had some major boat building experience.

If I do decide to attempt this change, I will attach chainplate straps on the outside of the hull and drill through and bolt to a backing plate as well as add some epoxy and glass layers to beef up that area of the hull.

You mention 25 degrees. Is that a standard?

Thanks again for the info!

Stephen

[Retired Geek]

Michael,

You mention 25 degrees. Is that a standard?

For sportsboats down our way 30 degree sweep on 6-8m boats is more the norm, especially if your going to be carrying large kites off a prod. I have been out in 35-40 knots with this setup with no problems at all.

Retired Geek