Jib Blocks for Light Air


Asheville Sailing Club
United States

My Scot is 5339 and is chomping at the bit to move up from second place at our club.  My boat has the jib sheet blocks at the jib car with the stand up springs and That is the 57mm block atop, what is it, about a 2" standing shackle held up by the spring.  I suppose the whole thing stands about 5" tall above the jib car.

I am reading the thoughtful suggestion by David Ames, and he claims this is a slow configuration, especially in light air.  Since light air is about all we ever have in Asheville, I put it to much wiser heads, what say you?  

Mr. Ames is sure that the block should measure just 2" above the car, which means, I think, a smaller block, strapped tight to the car.  I have seen this setup on any number of other boats, but always thought it was slower than the "proper" spring supported upright blocks.

The Flying Scot tuning guide is pretty clear that in drifting light airs, that the cars go all the way astern.  To my eyes this means that a more acute angle between the jib block and the clew.  I think the rationale behind having the cars back in light air, is that the back position flattens the overall shape of the jib, so that with less curve the slight airs have a better chance to flow through the slot.  I might be wrong about this.

The net effect of Mr. Ames' suggstion would be an ever smaller angle between Block and clew.

Always love the great thoughts by seasoned racers.   I will put the link to Mr. Ames' comments below.


Dgorwitz's picture

I think you are reading Dave's suggestion slightly wrong.  Just take out the spring.  You can have 2" between the attachment point on the track and the bottom of the sheave.  So, your 2" shackle is just about perfect.  In light air, the block flops over inboard giving you a tighter sheeting angle.  With the sprin in place, the block stands up and pulls the sheeting angle outboard.

jsailmo's picture

THat is my understanding as well - David's suggestion is to remove the spring. I have done that and replaced it with a small piece of white reinforced hose. Works perfect! The hose keeps lines from entangling under the block and protects the deck coaming but is flexible.