How to prevent chafe on my spinnaker halyard

[Privilege]

As my spinnaker halyard exits the mast head it rubs on the corners of the head and chaffs very quickly. Given that I have a large spinnaker with a 60'+ luff, would one of these swivel blocks attached a few feet below the head be strong enough for extended cruising? The block would have to be small enough to affix to the front section of the mast. Any suggestions welcomed.

[thinwater]

Unless you are a racer, pushing the chute far beyond good sense, the load on the halyard is typically about like your peak engine thrust, perhaps 500-1000 pounds at most.

Another idea (or do both) is to treat the rope with Yale Maxijacket. It reduces chafe in that sort of situation by 5-10 times. I have used it for many years on docklines, furler lines, and the like.

Knot and Rope has small amounts.

[markwesti]

Yale Maxijacket ? Interesting , I was just going to say sew some leather .

[Suijin]

Originally Posted by Privilege

As my spinnaker halyard exits the mast head it rubs on the corners of the head and chaffs very quickly. Given that I have a large spinnaker with a 60'+ luff, would one of these swivel blocks attached a few feet below the head be strong enough for extended cruising? The block would have to be small enough to affix to the front section of the mast. Any suggestions welcomed.

Not sure I understand the geometry of the problem and your proposed solution. The spin halyard exits via a sheave at the head of your mast, yes? It chafes on the sheave due to the varying angle of the chute, correct? Are you suggesting leading the halyard straight down from the sheave to the indicated swivel block, eliminating chafe at the masthead sheave because the run is now always straight to the swiveling block, am I correct?

[robert sailor]

When we are sailing offshore and flying the spinnaker for several days in a row I adjust the halyard a couple of times a day. Letting in out a few extra inches and then back but each time I try to find a new location so that it doesn't rub in the same place for too long a period.

[thinwater]

Originally Posted by markwesti

Yale Maxijacket ? Interesting , I was just going to say sew some leather .

I tested it on a chafe machine, along side some other materials, as part of an article on chafe. I expected nothing. What could something that looks like water-based varnish possibly do? I was stunned by how well it worked and now use it for many things. It is not very effective on Dyneema, though it helps a little. Best on nylon and polyester.

1. Docklines where chafe gear won't fit.
2. Furler line (I use it a lot as a roller furler, so it is under high load).
3. Most splices, in place of a thimble. (Not the rope-to-chain splice. It stiffens the line too much, although I bet it would work on an irony splice.)

I have not actually used it on halyards because I have zero chafe there. Just lucky. But unless there is an actual sharp metal edge, it practically stops chafe.

[rhubstuff]

Most of the racing boats I've sailed have had bails at the masthead with simple blocks attached so as to keep the halyard always leading fair off the sheave. You can use a messenger line to replace and re-reave the halyard when the chute is stowed, or not. This has the advantage of decreasing a bit of weight aloft.

[Suijin]

Originally Posted by thinwater

I tested it on a chafe machine, along side some other materials, as part of an article on chafe. I expected nothing. What could something that looks like water-based varnish possibly do? I was stunned by how well it worked and now use it for many things. It is not very effective on Dyneema, though it helps a little. Best on nylon and polyester.

1. Docklines where chafe gear won't fit.
2. Furler line (I use it a lot as a roller furler, so it is under high load).
3. Most splices, in place of a thimble. (Not the rope-to-chain splice. It stiffens the line too much, although I bet it would work on an irony splice.)

I have not actually used it on halyards because I have zero chafe there. Just lucky. But unless there is an actual sharp metal edge, it practically stops chafe.

Beyond addressing chafe, did it also help to noticeably help the lines to run with less friction? If so I have a few places to but it to use (furlers, right off the bat).

[UNCIVILIZED]

Pics of your stay attachment points, & sheaves, etc. are kinda’ crucial for us being able to diagnose this one. Or even a good mechanical drawing with dimensions, showing all of the rigging bits at the hounds, & tangs would be sweet. Otherwise it’s tougher to make suggestion, in that we don’t know the configuration of things up there.

One common bit of kit used at mastheads in order to reduce this kind of thing is to rivet or screw smooth, rounded over, stainless steel anti chafing strips on either side of the sheave. And I’m sure that this has also been done with things like UHMW PE. Much as it’s also been done on older ships with similarly shaped pieces of wood.

As to the proposed block. Does your spin halyard exit the spar far enough above your headstay so that you can mount such a block, & still have enough of a vertical gap for the kite to clear the headstay properly?
And either way, the bottom fasteners securing that block to the mast will definitely get a workout. As will the walls of the mast where they’re tapped into it.

Also, if you go this route, don’t ever plan on trying to fly a Code 0. The luff/halyard loadings will cause a lot of expensive s**t to self destruct in short order.