Tension Guge

[Jon Luscomb]

All right....I am working on repeating settings.

At the Sun City Regatta this past weekend, RMD came over after the seeding races and put one of those tension metters on my rig. He checked the back stay and said 2 to 2 1/2 lbs. is were it should be. (Thank You Bob)Breeze was 6-8 or so. Then Baron Bremmer came over with a tape and mesured my J- dimension...wasn't were he thought it shoul be, but placed the Jib boom tack hook at 7" and had me slide the jib boom counter weight back a little. What a diiference my boat was screaming!...It helped amazingly...now my questions are....rule of thumb tension settings for all shrouds etc. Is there a base setting that would then be changed as the breeze changes? Tightned as the breeze increases or eased as the breeze lightens? Rig forwad as breeze builds etc, HELP




I would rather wonder why I won than to know exaclty why I lost.

[Rick West]

Jon, see if this makes sense. BS tension used to be measured from a chart but that was when most were using Carr sails and there was a chart for his design and based on Jib Sag. That is the cut of the jib luff and measured in 1/32nd of an inch. Forget that but it did work.

Convention here is that if the jib luff knuckles on the water you need a little more tension. The general feeling is that you want the entry angle of the jib to have curve for pointing lift. This is the leading edge of a wing. The higher the wind velocity the more tension needed to keep the luff from collapsing This flattens the entry angle in the process. (Thinner wing)

What the gauge does for you, after taking notes on settings that work in the water, you can repeat the tensions known to be good from your sailing experience. Those of us that use the tensiometer trust it over the feely-feely of our fingers if one has any at all.

The gauge is also good when doing a basic tune on a rig. I start with 1.75# so that the rig and sails are set as they should be, smooth and symmetrical and with the "Race Look." Then all you do after that as the wind goes up is to move upward from a base. I call it, Pre-tune. That is the last step before the water.

In boats and airplanes there was a feeling not to place more stress into the action than was needed to get the job done.

I noted when you became a rocket, particularly on a starboard tack. You will do just fine.

...94

[Jon Luscomb]

Rick:

Thanks for your insight. I makes complete sense to me. I have a J-24 and have sailed it all around the East Coast for years and I have the Tuning guide from my sailmaker. I have evolved and narrowed that into what is fast for me and my boat. We are fast. Our direction and strategy is sometimes lacking, but the boat is never to blame. It seems that the same process will work here. The feely stuff on tension will come with time, but when we do well in the J, I always recheck the settings after the day to see where they are from the morning, note breeze, and note if we changed rig tension between races and note results...I assume that the EC-12 is similar in that they will be in and out of tune depending on velocity variations on the course. What I am aiming for is to find a tension which will have a wide range and will be good in a wide range of velocities.

I am curious...I noticed you have the vector rig...and you sail with pre-bend. Your shroud settings must vary from upper to lower. Meaning that say the lowers are at 1.7# and the uppers are at 2#..or say less than that to allow the mast to spill off at the top in a breeze...does the classic rig have a varience between upper and lower shroud tensions?

I will buy the gadget and see how it goes. Thanks again


I would rather wonder why I won than to know exaclty why I lost.

[Rick West]

The Classic single spreader rig can have a variance to suit to tuner; how soft or hard you want the air to hit the rig and where. This rig has manual pre-bend.

The Vector rig upper and mid stays are set, in my mind, to the luft curve of the main and I do not change the tensions after that. If I feel I need to spill of the pressure on the main, I go to the B rig. Before that I will change the tension on the lower stays to limit or allow bend introduced by the backstay as conditions change. The top jumper and the lowers control camber of the sail (flat to deep range it has) to the conditions. There is also a headstay bowsie in the mix.

The basic starting place with the rig is with the backstay slack. then stuff happens. This is not often possible with the Classic. This rig is only as complicated as your tuning style is. I try to keep it simple.

...94