I was reading an article in Sail Trim titled 'Halyard Hoist and Sheet Lead' by Norris Strawbridge in the Best of Sail Trim. Norris suggested using a dynamometer to measure the halyard tensions to help reproduce certain settings for certain wind/wave conditions. Has anyone else done this? I have never seen a dynamometer used in this type of application. Can someone suggest who would make such a device? Thanks.
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Doug T.
Hmmm !!!!
I don't know if it's been done before, but it would waaaaay cool if the winch and cam-cleat/v-cleat vendors would put digital readouts on their products that stated what the current tension/load was in kg or lbs............... Better still, have the winch/cleat/block sensors send the data via wireless technology to a central readout panel in the cockpit..... (!!! has anyone applied for the patents on this yet???)
I don't know if it's been done before, but it would waaaaay cool if the winch and cam-cleat/v-cleat vendors would put digital readouts on their products that stated what the current tension/load was in kg or lbs............... Better still, have the winch/cleat/block sensors send the data via wireless technology to a central readout panel in the cockpit..... (!!! has anyone applied for the patents on this yet???)
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Bill O'Donovan
One question
If you reduce the halyard tension, the sail will fall slightly. I would think the visual sense of the sail's shape would be a more accurate reading than the tension on the halyard, eh?
If you reduce the halyard tension, the sail will fall slightly. I would think the visual sense of the sail's shape would be a more accurate reading than the tension on the halyard, eh?
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Ray Bowles
Second question, Would the measured tension
of the halyard be influenced, by not only the strain of the winch upon the line, but also, by the strain of the wind upon the sail and its effect by deflecting the halyard? Is the measurement you are seeking better expressed as a strain measurement? Heck, just using a dyno on our drag racing motors is frought with variables, most of which we can somewhat control. The most important variable we can deal with in that sport is adapting the vehicle to the tract conditions as they change during the day. I would think this would be the best approach for a boat. You have a very close idea of the power available. The trick is applying it to the surface, whether it be liquid or solid. Ray S/V Speedy
of the halyard be influenced, by not only the strain of the winch upon the line, but also, by the strain of the wind upon the sail and its effect by deflecting the halyard? Is the measurement you are seeking better expressed as a strain measurement? Heck, just using a dyno on our drag racing motors is frought with variables, most of which we can somewhat control. The most important variable we can deal with in that sport is adapting the vehicle to the tract conditions as they change during the day. I would think this would be the best approach for a boat. You have a very close idea of the power available. The trick is applying it to the surface, whether it be liquid or solid. Ray S/V Speedy
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Don Alexander
Wrong Instrument?
Surely a dynamometer measures power (or torque and rpm) rather than tension and I cannot visualise anything other than a straight measurement of tension via a spring balance or the like. Further, I doubt if it would be of much use as, on my 376, the tension on the main halyard when measured at the winch (clutch open) was 50 lbs to just lift my toolbox off the deck. The toolbox weighed 10 lbs and this 80% loss of pulling power is why the Hunter mainsails are so darned hard to get up. Regards, Don.
Surely a dynamometer measures power (or torque and rpm) rather than tension and I cannot visualise anything other than a straight measurement of tension via a spring balance or the like. Further, I doubt if it would be of much use as, on my 376, the tension on the main halyard when measured at the winch (clutch open) was 50 lbs to just lift my toolbox off the deck. The toolbox weighed 10 lbs and this 80% loss of pulling power is why the Hunter mainsails are so darned hard to get up. Regards, Don.
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Barrie McDonald
Haylard Tension Gauge
Anthony, What you need is a device called a Rig Tension Gauge sold by West Marine. Look under Rigging Accessories in their catalog. There are two models, one a Regular gauge and the other called a Pro gauge. They are cheap, around $43.99 to $ 66.99 more or less. They are easy to use and work just fine. Good Luck, Barrie
Anthony, What you need is a device called a Rig Tension Gauge sold by West Marine. Look under Rigging Accessories in their catalog. There are two models, one a Regular gauge and the other called a Pro gauge. They are cheap, around $43.99 to $ 66.99 more or less. They are easy to use and work just fine. Good Luck, Barrie
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Doug T.
Tension gauges
The Loos rig tension gauges from the West Marine catalog aren't going to help you with rope tensions -- they are designed (and calibrated) for steel wire -- the standing rigging, not running rigging. There might be similar tension gauges for rope, but I haven't seen them.
The Loos rig tension gauges from the West Marine catalog aren't going to help you with rope tensions -- they are designed (and calibrated) for steel wire -- the standing rigging, not running rigging. There might be similar tension gauges for rope, but I haven't seen them.
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Cliff Ruckstuhl
Easy Fix
You can buy numbered strips from Layline that go from 1 to 10 in inch increments. I stall these infront of the rope clutch. Hoist the headsail and or main and mark the Halyard with a marker for the tightest setting when the wind is screaming at the number 10 position. And for lighter air go to the number 5 position and so on. You will than be able to duplicate you settings. Halyard Tension is for the sail shape only.
You can buy numbered strips from Layline that go from 1 to 10 in inch increments. I stall these infront of the rope clutch. Hoist the headsail and or main and mark the Halyard with a marker for the tightest setting when the wind is screaming at the number 10 position. And for lighter air go to the number 5 position and so on. You will than be able to duplicate you settings. Halyard Tension is for the sail shape only.
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Dave Teal
Tension accuracy
The masthead of my 1987 H31 has plastic sheaves and some small OD nylon rollers, so I would probably get false readings due to the friction they produce. I harden up so the sail looks good, put a reference mark on the halyard, then test performance with more and less tension. Sometimes, an inch or two can make a significant difference.
The masthead of my 1987 H31 has plastic sheaves and some small OD nylon rollers, so I would probably get false readings due to the friction they produce. I harden up so the sail looks good, put a reference mark on the halyard, then test performance with more and less tension. Sometimes, an inch or two can make a significant difference.
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Russ
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Don Alexander
Cunningham Holes
Anthony, Most sails have (or can be fitted with) Cunningham Holes. These are cringles a foot or two up the luff from the tack fitting into which a tackle is fitted. The tail of the tackle is led back to the cockpit and luff tension is adjusted by pulling down rather than by adjusting halyard tension and applies equally to mains and genoas. This has the merit of by-passing all the friction in the halyard blocks and gives a direct pull on the sail. The keen racers do it all the time, though it was more effective in the days of dacron racing sails. Regards,
Anthony, Most sails have (or can be fitted with) Cunningham Holes. These are cringles a foot or two up the luff from the tack fitting into which a tackle is fitted. The tail of the tackle is led back to the cockpit and luff tension is adjusted by pulling down rather than by adjusting halyard tension and applies equally to mains and genoas. This has the merit of by-passing all the friction in the halyard blocks and gives a direct pull on the sail. The keen racers do it all the time, though it was more effective in the days of dacron racing sails. Regards,
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