What leverage are people liking for 18 ft catamarans? I've got a 5:1 mainsheet block on my Nacra 5.2 and remembering last season that it tugged a bit (low to medium winds, lake sailing).
Harkem has a 57mm carbon triple that could get me to 6:1. This particular unit has a racketing system that engages under high load ... seems like it works like a car seat belt. Wouldn't that be bad if you caught alot of wind? Seems like it would tip the boat over.
The ratcheting system does not totally"lock", but it reduces the pull you have to hang onto. If you let the sheet slip, it will still play out, they do not totally lock up like a seatbelt.
My Harkens use it on both the jibsheet & main. I believe some of the newer ones you can adjust the holding power.
I don't need it on the jib, as I usually cleat it, especially solo. I never turn it off on the main, it really saves the arms on long sails on windy days when you might not want to cleat.
E C Hilliard
Nacra 5.7
Bombardier Invitation
The standard setup on a Hobie 18 is 7:1. If you're in the market for new blocks you might want to check out Nautos www.nautos-usa.com. Last Saturday I pulled the trigger on a new Nautos 57mm ratcheting base and triple boom block and the cost was literally 1/3 what I would have paid for a similar setup from Harken (Murray's pricing). I ordered the blocks online on Saturday and they arrived via Priority mail (free shipping) on Wednesday. I have yet to sail with them but I can tell you they look similar and have similar load ratings to the Harkens. And they came with a 5-year warranty. Cost me $129 total - both blocks!
Alternatively, I recommend checking out the block closeout section on Harken's online store (click the menu) http://www.harkenstore.com/uniface.urd/scwlcmw1.showPage . Good luck.
I had a 5:1 on my Nacra 5.2 to start and it wasn't even close to enough purchase for me. I switched to a non-low profile harken ratchetting 7:1 and then lucked out finding a lowprofile 8:1 for cheap. I still have the 7:1 blocks you can have to $100 plus shipping, let me know and I can send you some pics. Brian's idea looks good too that is certainly a good price for new blocks!!
Regards,
Dave
Dave Bonin
1981 Nacra 5.2
if you have access to some old triple blocks you can upgrade your current 5:1 to 7:1 by swapping the double blocks for triples, worked for me
http://www.thebeachcats.com/pictures/?g2_itemId=86798
edit, wolfman's 7:1 above is very good value
the ratchet locking system works by locking the wheels not the sheet
with no ratchet selected the loads go both ways, you pull 10kg, boom pulls 50kg
boom pulls 50kg, you need to counteract with 10kg
with the ratchet on when the boom pulls it still tries to pull the sheet through the system but it can't as the ratchet has locked
however the sheet is still free to slip over the locked ratchet wheel but is held up from doing so by the "grippers" formed on the ratchet wheel
so the load to the sailor is greatly reduced
slippage by the sheet over the grippers on the locked ratchet wheel will slowly break rope fibers and degrades the sheets strength
Edited by erice on May 05, 2012 - 07:09 PM.
1982 nacra 5.2
2009 weta
Remember when you go from a 5:1 to an 8:1 there will be a lot more mainsheet needed. Result will be more to sheet in and more to payout to depower. You can add a pigtail between the upper blocks and the boom to reduce this. If you are able to use an 18 inch pigtail without going block to block you can remove approx 8X 1 1/2 feet of line or 12 feet, if only a 1 foot pigtail 8 feet of line.
Thanks for the quick replies; I may take Wolfman up on the 7:1. I thought the 5:1 was pretty tiring, and it looked like most of the other racers had dual set of 3 pulleys.