I rigged 6:1 purchase on my main by using a triple (not fiddle) block on the
traveller, and three blocks on the boom. Aft block is a single w/ becket
(sheave cross ways to the boom), middle block is a single also cross ways to
boom, and forward block is a single, sheave in line w/ boom. The sheet then
goes forward to the gooseneck, and down. The triple on the traveller has
the sheaves in line w/ boom. Works very well, and spreads the load on the
boom some.

I don't know how you rigged your blocks, but I have seen traditional multi
sheave blocks rigged with the sheave shafts parallel to each other.
However, it is much better for the two shafts to be perpendicular. You can
better balance the forces between the blocks so they don't get cocked over.
I rigged the outboard motor lift on our old cat that way 6:1 (actually 12:1
final) so my wife could manage it.

"Steve" wrote in message
...
I need to increase the purchase on my main sheet, so I don't have to go to
a
winch when trimming.

I designed my mainsheet around a diagram and picture in Sail Power,
however
I have never been able to locate triple fiddle as there is illustrated in
Sail Power.. (I think it is a Meriman). The book is on the boat right
now.

I have tried using a traditional (side-by-side) triple but in light air
the
block tumbles and the lines cross and jam in the other sheaves/lines.

I have been working with Garhauer, looking for a solution but it looks
like
I may have to go with a custom block ( made from their double fiddle
w/becket).

BTW. What I need must take a 1/2" sheet.

I know they have existed at sometime since I have a picture in Sail Power
(or maybe it is in one of Henderson's books)..

Anyone have one laying around??

Steve
s/v Good Intentions