Drilling new holes in the mast

[Seajet]

Dan,

in the early 1960's when the boats were built, makers got a mast extrusion and rivetted on the end fittings by the few suppliers - job done, and sailing was supposed to be character forming, if it was difficult it was doing you good !

I strongly suspect your shinier sheave was a replacement.

The question with new sheaves is where you're going to lead them; to some extent the old systems like Spinnaker halliards and downhauls - an endless line - got away with a low horizintal pull by being led aft alongside the centreboard for the helmsman to use along with the guy and sheet while the crew fiddled about with the pole; but you will need something like a ' Tillermate ' and halliards etc probably central in the boat for ballast / trim reasons.

Either way it makes sense to have all the halliards easily to hand - and working smoothly - around the mast area.

 

[anoccasionalyachtsman]

I'd replace the two sheaves in your existing box, possibly with something like these http://www.ebay.co.uk/itm/Holt-Alle...749538?hash=item58cf57a4a2:g:9DoAAOSw~bFWG9fN, but speak to Holt Allen and see what they've got. It's easy stuff to turn down a bit, and you could bore them and put ball races in if you wanted.

Then I think I'd move the cleats off the mast and put them on something that's in line with where I'd like to be when hauling - possibly the centreboard case or thwart?

The above assumes that you do the final tensioning by pulling the boom down - if not you'd be better off with a lever or muscle box than using those cleats.

 

[bbg]

Dan, looking at your setup, you might get by with lashing (very tightly) a single Antal low friction ring to the mast in the upper "splayed" section. Do you use that horn cleat at all? A lashing would go all the way around the mast, so that horn cleat would get in the way.
There should be no issue in leading two lines through the same ring, provided it is larger enough to accommodate both, and they are led in slightly different directions.
This would give the advantage that the angle of pull is not at all critical.
Personally I would also think of replacing the clam cleats with proper cam cleats.

http://www.antal.it/eng/195_low_friction_rings_en

Edit - just to be clear, in the setup I imagine, the ring would be lashed horizontally, so the opening of the ring (the central hole) would be pointing up and down, and the two lines would come down through that central hole. As I think about it, however, that might lead them slightly too far aft - it depends how deeply into the mast groove you can fit the ring - with the result that the halyards might chafe on the mast groove above the ring.

 

[Greenheart]

Many thanks once again - every suggestion here has drawn my attention to options I hadn't considered, and any of which would be better than the way my halyards were rigged. Cam jammers are more appealing than my clam cleats, and those Antal rings certainly must be a slick way to divert lines without adding friction.

I took a photo this evening, showing the section of the mast between the gooseneck and the point at which the mast emerges through the foredeck, around 24" above its foot. In the picture, I've led both halyards out of the track below the gooseneck, to the lowest points on the mast which would still be clear of the deck...sorry, the mast isn't aboard the boat, the backdrop is actually the ceiling...

...now, if I riveted the cleats into those positions, I'm thinking that the problem will be more or less over - it wouldn't be the neatest solution, but it probably will be the simplest, and would leave the halyards very accessible, and easy to swig tight, and they would release quickly, and the halyard tails will practically fall into the bags I've fitted to hold them.

I'll go over every post here again before I drill any holes, but is there anything obviously stupid about my new simplistic approach?

 

[bbg]

Chafe.

 

[Greenheart]

Chafe.

Hmm, good answer, if not exactly what I wanted to hear.

So...if I can scribble on my photo (sorry, all my natural impressionist talent is still asleep this early)...one of those low-friction Antal rings (green) lodged horizontally at the top of the flare in the track, and held into that section with immovable tension by the pink line, will let the halyards turn the corner out of the track, with reduced chafe?

Sounds very reasonable to me, and a lot simpler than sheaves. It also occurs to me that (as I understand it) chafe mainly happens where there's movement, and most of the movement of my halyards is during hoisting/lowering; so I'd expect those lines to be very tight and more or less fixed relative to surfaces around them during a day's sail...

...and with an Antal ring to ease their passage out of the track, I can hopefully go sailing and stop bothering you gentlemen...:encouragement:

...any more recommendations?

 

[bbg]

Yes, you have understood my suggestion correctly. Whether it gives a fair lead will depend on the geometry of the placement of the ring and its size.

If you go down that route you will need to size the ring large enough so it can take the two halyards comfortably.

If it were me, and I had confirmed the geometry properly, I would probably file a couple of small grooves on either side of the (splayed) mast track to accommodate the ring and assist in holding it from sliding up and down the track.

I would also try to fix it to the mast with quite small diameter (4 mm? 3 mm?) dyneema. The way I would try, in the first instance, to fix it would be by having a relatively loose splice in one end of the dyneema that goes around the ring. Then around the mast. I would then try to take the line fully around the ring (under, around and back over) so it comes back from where it came.

Ideally back around the mast again (this time in the opposite direction) and if possible around the ring again. In order to cinch the ring really tightly to the mast, I would finish off (after the line has gone around the ring - not as it comes off the mast) with a round turn and two half hitches around both parts of the line i.e. the part that has gone under the ring and the part that comes out over the ring.

By pulling these two parts of the line together you will cinch them tight and should get a really tight grip on the mast. I can try to post a drawing if that is not clear.

 

[bbg]

It also occurs to me that (as I understand it) chafe mainly happens where there's movement, and most of the movement of my halyards is during hoisting/lowering; so I'd expect those lines to be very tight and more or less fixed relative to surfaces around them during a day's sail...

No matter how tight they are, there will be chafe. You probably won't notice it in a day or two, but if you use the boat regularly there would be chafe in the photo shown in your post 24 over the course of a season. And you don't need the expense of replacing the halyards.

 

[Greenheart]

Thanks again; I'd like to get the ring (or rings...I can think of various applications for those) then get busy fitting them. Although, there's another problem related to chafe...

...the inside of the gooseneck seems to be a rather sharp-edged bolt-end and steel plate to which the outer fitting is fastened; when the halyards were led straight down inside the mast to the sheaves at the foot, they made no contact with metalwork in the track. But drawing the halyards away from the smooth tubular section of the mast and out towards the opening in the track, risks fairly constant contact between the lines and the sharp inside edges of the gooseneck.

If a something could be secured inside the track to hold the halyards flat against the inside of the mast until they're below the gooseneck, they could then be led out at the flared point through a ring as planned. Perhaps a smooth stainless pin could be drilled across the track below the gooseneck, so no lines can be hauled outward above that point?

 

[Greenheart]

I do hate it when I think my solution is coming along in big strides, then suddenly it looks less workable than the original set-up.

I commend everyone who is still following this thread, for their patience.

To recapitulate, the problem which I began by asking about, was the rotten position of my clam cleats, relative to the exit box at the mast-foot...

...now, those cleats could easily enough have been moved up to foredeck height, giving a nice fairly straight run to ease hoisting and lowering, and enable swigging...

...but on close examination, the exit box itself is a worse problem, with sheaves all crumbly and reluctant to turn freely...

...so now, moving the cleats doesn't feel like a question worth asking, just twenty minutes' work...

...whereas, putting new sheaves in that exit box is a daunting prospect, since it is held in place apparently by welded rods rather than bolts. It's even tempting to fire up the angle-grinder and cut away the old exit-box to make room for a new, cheap, sturdy hollow-spindle double block which could bolt in place down there, so the halyards could return up towards the relocated clam cleats near the gooseneck, as originally planned. Any thoughts on that?

 

[Seajet]

Dan,

why hollow spindle ? I'm all for weight saving but that seems a tad extreme.

I'm finding it hard to imagine cleats above the mastfoot sheaves - even new ones - with a fair lead; I think the original ones maybe had ideas of being led aft - or possibly that's being too kind to the 1960's gits.

I'd still leave that abomination alone for structural purposes - it will need something to replace it within about 20 years, by which time you'll have a Sydney 18' Skiff and a Hallberg Rassey - and fit completely separate ball bearing sheaves & cleats.

 

[Greenheart]

...why hollow spindle?

Because, since nobody produces the right size of exit-box to fit in that narrow little slot, I'll just have to put a double block in there...and if it has a hollow spindle (like those cheap 'Seasure' blocks), I can hold the thing rigidly in place by bolting through the bottom of the mast. If it doesn't allow through-bolting, the block will twist around under load.

You may be right about where the halyard cleats originally were...who can say? I only know what a rotten job the last person did; a tight diagonal twist over a short distance...awful. Letting the halyards run up two/three feet from the exit box to slightly offset cleats may not be perfect, but will be far easier than what I've put up with for three years.

I wonder what the procedure would be for replacing those old zinc sheaves? Do I drill through the rod which holds the sheaves, and replace it with...some thick stainless bolt?

 

[anoccasionalyachtsman]

The rod will just tap out, but may need a soak in ammonia first. I showed you a link for new sheaves wheels.

 

[Greenheart]

I showed you a link for new sheaves wheels.

Thank you, I hadn't forgotten that.

Actually sheaves seem far less difficult to source than the compact little structures which hold them, and which must either be the right shape and size, or useless.

I'm relieved if you think the sheave securing rod will ease out without much difficulty. Do you have any view on shifting those pins which fasten the exit-box to the mast?

I'm thinking they'll need delicate work with the grinder or drill, or both. I suppose when the box is removable, there'll be holes through which I'll be able to push new 316 bolts.

 

[Seajet]

Because, since nobody produces the right size of exit-box to fit in that narrow little slot, I'll just have to put a double block in there...and if it has a hollow spindle (like those cheap 'Seasure' blocks), I can hold the thing rigidly in place by bolting through the bottom of the mast. If it doesn't allow through-bolting, the block will twist around under load.

You may be right about where the halyard cleats originally were...who can say? I only know what a rotten job the last person did; a tight diagonal twist over a short distance...awful. Letting the halyards run up two/three feet from the exit box to slightly offset cleats may not be perfect, but will be far easier than what I've put up with for three years.

I wonder what the procedure would be for replacing those old zinc sheaves? Do I drill through the rod which holds the sheaves, and replace it with...some thick stainless bolt?

Dan,

if you really want to replace that lot - I don't see why as you'd still have unfair leads to any cleat - I'd suggest first filing the rivet heads flat, then a centrepunch and cordless drill; with luck you might get long shank stainless bolts so the bearing part is plain not threaded, but they would be overlength so a pig of job to cut, angle grinder being the best bet.

I'd draw a discreet veil over the whole lot and start again somewhere sensible !

 

[Greenheart]

I'd draw a discreet veil over the whole lot and start again somewhere sensible !

Hmm. I'm in danger of confusion now Andy, from so many excellent but conflicting contributions.

If I was to 'start again', I can't easily see where, nor how. The foredeck-level exit-point is still appealing, but has its own distinct difficulties.

When I began this thread, I was only conscious of the inadequacy of the cleat positions. Now, my attention is mostly on that exit box, which (if it cannot be eliminated from the solution) has to be replaced or repaired. Wherever the halyards are led to when they leave the mast, they must first leave the mast...

...and right now they've no workable route out. I was thinking removing the exit box and reassembling it with new components, is my best bet because it's easiest. No?

 

[bbg]

I'd draw a discreet veil over the whole lot and start again somewhere sensible !

Agreed. He should just sell this boat and buy one that is already sorted.

 

[Greenheart]

Oh, that's rotten. I bore everyone here because I love that old boat so much, I'll never sell her...so I have to find a way to fix her up.

Plus, I reckon with the right blend of imagination and handiness, (and some good advice) I can make old systems work, virtually for perpetuity.

 

[Kelpie]

Could you use the existing crumbly sheaves as a strongpoint and lash on a couple of floating blocks? So the halyard comes down as currently, to a new block lashed just above the defunct sheave, then the halyard does a 180 to be cleated at a new position much higher up on the mast. Would be very cheap, very quick, very easy, and completely reversible. Remember that the best is the enemy of the good

 

[Greenheart]

Sounds like a handy solution Kelpie, but don't forget there'll be two halyards turning 180 degrees, so there'd be two floating blocks and there's really not much space...

...I like the idea, just can't visualise it because I can't see them fitting in the space available.