Sail handling without winches

[ms.lau]

Hi, as part of my interest in keeping things simple, does anyone know of a good reference source for the physics of using a block & tackle for sail handling instead of a winch? Thanks.

[sailorboy1]

You think that will be simpler , I don’t

Buba mechanicl design book would do it. Or a quick internet goggle search

[ms.lau]

At sea, I think it would be much simpler to fix than a boken winch.

[Rucksta]

In the unlikely event a winch was to break lead the tail to another winch.

[Mickeyrouse]

Winches are a fairly recent development in sailing. I believe the first winches for small boats appeared in the 1920’s. Before then it was all block and tackle. Even the big sailing ships didn’t get large Jarvis winches until the latter half of the 19th century. Block and tackle takes somewhat more muscle power, which is why winches eventually were developed.
One problem with block and tackle is the amount of line needed for each sail. For example, with a four part tackle a Genoa trimmed for a broad reach, you will need four times as much line for trimming and control compared to a sail trimmed via winch. And keep in mind that that multiple applies for each sheet and halyard and possibly traveler on on your boat.
If you examine photos of sailing vessels from back when, you will note the large coils of line around mast bases and on racks where the sheets were secured.
On a typical cruising boat the cockpit or side decks is where the line will likely be resting. Do you have room for four times as much line as you now have? On our boat the total length of the jib sheets is 80 feet, both sides. A four part block-and-tackle rig would be 320 feet. That’s a lot of line in the cockpit., and a lot of weight on the sail that light air has to lift. And imagine the tangles when sailing with guests. We have a 3-part arrangement on the main sail. It’s about 350 feet. It is too big to trim without a winch in all but the lightest air.
Next is the matter of blocks. Assuming you’re sailing something in the cruising size, the afore-mentioned four part system with require either sets of fiddle blocks or (more traditional) double blocks. I believe if you price them, you’ll be close to the cost of a winch for each control line by the time you figure in the cost of a quadruple sheet system. Blocks will last a long time, sheets and halyards not so much. By the time you figure in line replacement cost I doubt there will be much economy. One of the factors of operating costs the old sailing ships contended with was chafe- it required constant line mending and replacement.
I realize your question was about physics. I can’t help there much,but you’ll be calculating force exerted in pounds at a given wind speed on a given sail area, then dividing by the a mechanical advantage of your block and tackle, depending on two part, for part, six part, whatever. The answer is the physical force in pounds required to trim a particular sail at a given wind speed. Sailors have been able to control and handle sails for centuries without winches, but as the breeze turns into wind, it begins to require real muscle power.
If you’re still into the idea, I would suggest referring to Howard Chappelle’s books on American small sailing craft and the fishing schooners. He may have notes on rigging.

[Lake-Effect]

Originally Posted by Rucksta

In the unlikely event a winch was to break lead the tail to another winch.

This.

If you're still concerned about your winches, you could always make up and store a spare block-and-tackle assembly (maybe 4:1) that could be used in an emergency. But for daily use... winches.

[tkeithlu]

That was a really good treatise on blocks, Mickeyrouse.

A winch is one rather simple mechanical device supplying the mechanical advantage of a very complicated and heavy block and tackle, and without the friction and chaffing that comes with the line going through all those sheaves. If you are trying to keep it simple, the winch wins. Both blocks and winches require maintenance, basically periodic disassembly, cleaning, and lubrication. There is one small advantage to the block system - you can use lighter line, but a whole bunch more of it.

[Rucksta]

https://www.harken.com.au/Calculators/

Harken have a handy load calculator.

[ms.lau]

Thank you for your replies so far. I'm currently "between boats", last one was 34' but I'm thinking of more like 24' next time. I'm just looking at the cost of outfitting and the price of gear. The price of a small secondhand winch seems to be quite massive. Why use stainless rigging instead of galvanised? Moitesseir was keen on using clamps instead of splicing steel rigging. He also talked about greasing halyards (and sheets?) to make them last longer. A boat without an engine... All these things are interesting to consider...

[ms.lau]

Rucksta, thank you for the Harken link, that was more what I was looking for rather than the pro/con thing, though the conversation is interesting! It helps to understand things from basic principles.

[Pegu Club]

Not that older technology, methods and practices don’t work, They do, but you will work a whole hell of a lot harder than you would using a winch, by the time you purchase all the blocks and line etc, a few winches for a 24 foot boat won’t be much more money if at all. Lots of winches to be found in marine consignment stores that are cheap and work just fine, it’s the self tailing variety that cost more. The sailing world By and large has moved on from that technology, it may be fun to entertain going old school, but you will likely not be so impressed with it in practical application.

Fair winds,

[radsailor]

On a J 80 I rigged a 2:1 purchase for the jib sheets. One block for each sheet on the jib clew with sheet dead ended on each jib lead car. Worked very well.
I had winches, but for solo sailing this seemed a little easier.

[Chris Cringle]

Ms. Lau, For 22 years I sailed all over the Pacific and Indian oceans in an 1880s designed 18 ton gaff-rigged ketch. She had no winches. For the main sheet we had a six-part tackle and a three-part tackle for the mizzen. These were way more than enough to handle the sails. For the head sails, jib and staysail, we just used a single part jib sheet/staysail sheet. When we would tack, we would over-trim the headsails and then gently start them until we had the proper trim. If we need to trim in without tacking, we would simply luff-up, trim the sail, and then fall-off. People have been sailing for thousands of years; sheet winches have only been common on yachts for a few decades. Keep It Simple Skipper

[grantmc]

Originally Posted by Chris Cringle

... For the head sails, jib and staysail, we just used a single part jib sheet/staysail sheet. When we would tack, we would over-trim the headsails and then gently start them until we had the proper trim. If we need to trim in without tacking, we would simply luff-up, trim the sail, and then fall-off. People have been sailing for thousands of years; sheet winches have only been common on yachts for a few decades. Keep It Simple Skipper

The important word there is gently. Nice post Chris Cringle.

On a 26 foot keeler I rarely use the sheet winches, just tack gently. And by the time the boat has tacked you've already sheeted in by hand. Helm needs to by careful about the course required on the other tack and in changing course the boat points just a few degrees higher. That allows the sheet to be pulled in tight (a little over sheeted) and then as the boat settles on the new course and gains boat speed again, the wind will move forward, and you can just very gently let a little sheet out as she settles.

The method avoids considerably less stress for the crew and the gear, and the result is almost always less speed loss on the tack. Most people sadly learn to tack by violently swinging the tiller, typically oversteering in the process. If you have to fight the sheet after a tack then it's obvious you oversteered.

Competent dinghy sailors are usually very skilled at this as their boats don't have winches.

It's also a handy skill for the racing single handed. You only have two hands, and a winch needs both. Most winches on little keelers don't self tail.

This of course doesn't help for our OP with his block and tackles, but I thought it's interesting to mention. Depends much on the type of sailing. Unless racing, then tacks are a relatively rare event anyway.

Oh and in respect to stainless vs galv, it's superficial it's about aesthetics. Plenty of yachts out there with galv stays.

[Jdege]

Originally Posted by Rucksta

In the unlikely event a winch was to break lead the tail to another winch.

My boat only has one winch.

But then, it has smallish sails.