How to make my boom shorter?

[antonputman]

I have only one boom, a North Red 160-210cm

Now I just bought a used EZZY Panther II 4.2 to add to my quiver.
The specs say, boom: 154-158cm
http://www.ezzy.com/allyearsezzys/2010/specs/panther_10.htm

Any tips on how I can make my boom "shorter"?
Maybe put something inside the clew or something?
Hey it's only 2-6cm...

How about just keeping the line from the clew? Will it be that bad?

[isobars]

Most of us just cut the boom arms shorter and VERY carefully drill new holes in them. First, however, I'd rig rig the new sail and determine for a FACT how much distance/line you'd have between the boom end and the sail clew. A couple of cm is not noticeable except in frequent maneuvering, whereas several cm is very noticeable.

Do you not have access to used gear? Good short booms can sell for low double digits.

[antonputman]

How about a cheap halyard shackle you can buy in every ship shop, would that work?

[isobars]

Sure (so would a loop of rope), but the slapfest will drive you nuts and perform poorly.

[antonputman]

Ok thanks I try it when I will receive the sail.
I think if I find one of those shackles with a tight fit for the grommet of the clew, it will be better than a loop or even webbing.

[isobars]

The problem is the distance from the clew to the boom, not whether the link is unobtanium or taffy. Too much distance lets the clew flap back and forth under changing loads, letting your sail shape change quite abruptly. That's why, back when short booms were hard to find, we'd outhaul the sail properly then tie the clew off to one boom arm or the other, solving the sail shape issues pretty well. It's an effective bandaid.

[dllee]

First, read the specs of your biggest sail for that boom, and allow for 5" of extra underlap.
The cutting and redrilling is pretty basic but time consuming.
Cut the boom, not the extension that goes inside the boom.

[swchandler]

If you anticipate cutting the boom arms, you have to make sure that the adjustable extension ends won't hit a plug or the curvature in the boom arms.

Also, from the sail specs that you identified, the maximum outhaul is only off by 2cm, a pretty small distance overall. You have to ask yourself whether sailing in 4.2 conditions really focuses more on the minimum outhaul (154cm). It has to be pretty windy for me to pull out my 4.2 (my smallest sail), and I have to admit, I'm usually not focused on bagging the sail out in 4.2 conditions.

What's your next sail size up?

[mark]

Before cutting the boom I would rig up the sail and outhaul the sail so that the distance from the front edge of the mast to the outer edge of the clew is 158 cm. The measurements on all booms are not consistent. 160 cm may be the distance from the where the mast seats to just inside the tail piece. If you are using a mast shim for an RDM mast you lose about 1 cm due to the shim thickness. Also depending on the outhaul arrangement you may not be able to pull the clew all of the way to the tail piece. It may be several centimeters from touching it.

Ezzy sails also take quite a bit of positive outhaul so there is quite a bit of tension on the outhaul. I doubt that the clew will flap around. You are talking 2-6 cm not inches.

No need for a shackle. Just rig your outhaul line as you normally would. At most you may need a slightly longer piece of line.

[antonputman]

Forgot to tell, no cutting as I need the same boom for my biggest sail, a 7.8 with 207cm max boom.

I would just hate to have to find a new boom for a few centimeters.
Also I just replaced my 160-210 North boom because of breakage.

Anyway, I will see if the sail arrives. Cheers guys