Rope masthead sheaves and topping lift questions

[Cool Beans]

Have I said yet how Awesome you guys are?



The mast is currently off the boat while I figure out how who I want to re-rig it. . .I want to go to all rope halyards eventually, but the only questionable one is the main and I will probably just replace it for now. Can you tell by the pictures if the sheaves that are installed are the combo ones I can use rope with? They are "U" shaped with a groove in the center. . .or do I need new ones?

Second questions is, can use the second masthead sheave for a rope topping lift? Is there any reason I couldn't? I would like it to double as a safety line for a bosons chair. Currently, as you can see in the pic. . .the topping lift is a fixed wire and is adjusted at the boom (which sucks). If it was adjustable at the mast I could at least raise and lower the boom without having someone in the cockpit to hold it

Thanks!!

 

[Roger Long]

the topping lift is a fixed wire and is adjusted at the boom (which sucks).

Actually, it is a very good arrangement. Since the topping lift is generally slack underway, having a running part down the mast is a recipe for noise and fouling.

Deadend it at the masthead and put a small block on the lower end. My lift is plastic coated wire which I've found very satisfactory. It's the only place I would use such wire on a boat.

Put a small becket block on the boom end with a short rope tail spliced into the becket. This goes around the topping lift block and back around the boom block. Another line is attached to this with a sheet bend. The purpose of the knot is so that the tail can be just the right length for the boom to be held at the lowest desired angle. That way, if someone accidentally casts off the topping lift, the boom won't come all the way down.

If you want to control the topping lift from near the mast, just lead the second line forward to a cleat. I like to be able to adjust the topping lift from the cockpit. Even though I handle my halyards and do my reefing at the mast, I haven't found a need to adjust the topping lift from there. My topping lift goes through a cheek block at the forward end of the boom, down to a block shackled into the shackle for the boom vang, and then to a cabin top during block and aft. The line that runs along the boom is small diameter 3 strand nylon to minimize the bulk along the boom. It also has some give in case the hard sheeted main pulls down against a topping lift set up too tight. This line is too small for easy handling so a short length of larger line is tied on just after of the turning block.

I also worked two ends of a small diameter shock cord into the line along the boom about 1/3 of the way back. The loop goes through the eye of an adjustable rope tail which is tied off at the gooseneck. This does a great job of keeping the topping lift from slatting around.

After a fewl thousand miles with this arrangement, I can't think of a way to improve it.

 

[catsailor]

Two more thoughts, having gone from wire to rope halyards:

• Make VERY sure there are no burs or sharp spots on anything. Spin the blocks and smooth them all the way around. It probably is not required to switch to rope blocks if you use spectra; I did not.
• Consider using a knot in place of a splice at the top. It depends on the hoist and the block spacing, but on some boats the splice can jam or wear badly. Heck, if a splice doesn't work out, just make certain you have ~ 4 feet of extra line so that you can refresh the wear area as needed. remember, however, that splicing used line is a bear.

 

[Roger Long]

Two more thoughts.

Both of which I will second.

My sheaves were badly chewed up by wire halyards. I found a plastic spacer in the hardware store the diameter of the sheave pin and put a bolt through it with a washer on each side and a nut. Chuck the bolt in a drill and hold sandpaper in the groove.

I use a Buntline Hitch

http://www.animatedknots.com/buntline/index.php

on my halyard shackle and it gets the sail higher up that mast than a splice would because a splice has a long thicker part in the rope which can also jam in the sheave. It's also a lot cheaper than having someone make a splice for you or spending a couple hours figuring out how to splice double braid.

This is a very useful knot which I use many places. Beware though, once there has been significant strain on it, it is about as permanent as a splice. For heavy duty, use only where you would consider a splice.

 

[Cool Beans]

Thanks all for the insight and information, sorry it took so long to respond