Thread: A bent yard?

Nick, are you making the sail, or is the yard being used with a bought sail? Might work well, and everyone will ask how you shaped it!!

I had a curved centreboard and it worked great. No idea why. The Dutch specialise in bent yards, they should be able to help.

Brian

Hello,

It would work fine I guess, as long as you would take the pre-bend of the yard into account when shaping the head of the lug sail (the draft is initiated in the sail through the head).

The Dutch gaffs have a bend in them, but believe me, the sailmakers here know exactly how to cut the sail to ensure a perfect "wing" on the traditional boats.

Best regards,

Joost

Hi, thanks for the info so far.

Its for the PDR, im building as per Miks Lug rig for the PDR. SO which way would be the ideal direction to have the curve, that is, curving away from the sail or towards? and then would you take out curve from the sail?


..,,---'''''''''---,,.. yard - middle bends away from sail?
---------------- sail

''''---,,....,,---'''' yard - middle bends towards the sail?
---------------- sail

TA

Howdy Nick,

Sorry, I've been out of circulation with PDR stuff.

It probably doesn't matter a great deal.

Also when you measure up the yard it maybe possible to strike a centreline and measure out from there - that way the curved edge becomes part of the taper.

Or you could take all the taper out of the concave side and don't change the convex one at all.

So that is on the rectifying side.

If you are stuck with a bit of a bend it probably doesn't matter as the load to pull out a small bend will only be small in relation to the total forces that are trying to bend the spar.

Another way to look at it is you now have two options. You can power the sail up or flatten it off just by flipping the yard over and relashing it.

BTW ... how much bend do you have?

MIK

Hi Mik.

The bend is on the thicker side of the taper, about 12mm over half the length of the yard.

Now with the yard, does the thinner end go toward the head of the sail? much like the boom with the thin end out at the clew...

The yard is now 16ish sided. Off to get some sandpaper in the morning for final rounding and smoothing. Then Ill finish it of tomorrow with the fiber glass tape on the ends and epoxy coating. Sunday is sail making day... Monday will be testing the rig in the garden and sorting out the trailer and dolly system.

I'm lucky to have next week off, so hopefully get a good bit of sailing done! The varnishing of the spars can wait till when I go back to work, I'll do them one evening and they can have the week to dry, no use wasting holidays watching varnish dry....

We have a new digi cam that is water proof so Ill take that along a make a few vids....

I thought it was symmetrical, but you have the plans in front of you!

Yes the thinner end goes at the top

MIK

You had me worried there Mik. I had to go and check!. It is asymmetrical...

So after shaping (string centre line) it only has about 12mm of bend... not too bad?

Not too bad. Feel how much effort it takes to straighten it.

It is not a great deal. That is what you are up against.

Choose a side and go sailing. If you think the other side will work for you in terms of finding a bit more or a bit less power then flip it over.

MIK