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John, in this image I think I am looking at the throat of the sail, the front of the the yard.

If that is correct, I just want to offer advice on one point. The way you have rigged the red line securing the sail stops the sail being pulled up the yard but not down the yard. The throat cringle needs to be secured both ways.

When you apply downhaul to the sail, which is very important in a balanced lug sail, all that tension goes up the luff to the throat. What is needed, and is very important, is to keep the throat in place and not pass all that tension on up the yard.

The way you show in the picture the red line does not hold the cringle at from sliding down the yard. It will simply go slack when downhaul is applied. The cringle would move to the right, the line around the yard would slide to the right. Too much tension would then travel up the yard and before you have enough luff tension the head would be too tight and very creased.

What is needed is a way to stop the line which goes round the yard from moving down the yard. This is easily achieved by adding a SS eye to the top of the yard where the line goes around the yard. the line passes through this eye.

With the eye in place properly holding the cringle in place, here's what happens when downhaul is applied. all that tension goes up the luff and helps raise the yard high and makes you go really well upwind. To achieve the correct yard/head tension you adjust the head cringle position by adjusting the line securing the cringle at the head of the sail.

On my sail the head cringle is loose with about 1" of movement. When the downhaul is applied the throat cringle still pulls forward a bit until the line tightens and this movement forward takes up the looseness up at the head.

I feel sure some people reading this will think it seems a bit too complex, but it is the whole secret of sailing upwind with the balanced lug rig.

I tried to explain all this in a SCAMP sail tuning document saved here

https://docs.google.com/file/d/0B4Bi31i ... N4Y1U/edit

Brian

G'day Brian

Thank you so much for this most timely piece of feedback on rigging my sail. I do now remember making a copy of your addition to the rigging and had forgotten all about it ! This is the first time I have rigged a balanced lug sail and my inexperience is showing.

Again many thanks for the heads up on this one. I include a copy of your diagram so that others may also benefit.

Cheers - John

G'day Folks

Here is an updated version of fixing the throat to the forward end of the yard. Halyard will be attached to blue strop using a double sheet bend !

Cheers - John

Just a few shots of the current state of build !

Cheers - John

Merry Christmas everybody from Tasmania. Just bolting on the the final bits and pieces then into the water she goes. Sorry about the red main sheet hanging from the roof, it is there to help lift the boat. I will probably fix it to the end of the boom in the near future !

Cheers - John

Looking awesome Tasman. No need to apologize about the red line, I thought it was a Christmas bow

I'd love to see a shot or two of the finished cockpit. How are you hauling the centerboard? How about handling the main sheet?

Congratulations!!
Beautiful boat and an inspiration for all of us in progress with our builds.
Merry Christmas,
howard

Lovely blue Scamp! Looks great.

Mike and Jackie Monies

Thanks for all the great comments and feedback. Finished her yesterday, including the trailer ! Next step is to see if she floats. More pictures shortly.

Cheers - John

Tasman,

I, for one, am extremely jealous. Athough not as much as I would be if I wasn't as far along on my own boat . You did an incredible job!

I can't wait for the Sea Trials report!