Mast tuning guide

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Mast tuning guide

Postby i550sailor@aol.com » Sat Jun 13, 2015 6:22 am

Does anyone have a mast tuning guide for an aluminum rig, or can share what they are doing for shroud tension.

Thanks
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Re: Mast tuning guide

Postby Chad » Sat Jun 13, 2015 12:45 pm

Set rake with head stay and I-point shrouds, then crank I-points until 150% of mast bend is achieved, then crank D1's to remove excess bend. Check forestay tension: grab and wiggle 6' off deck, and add tension until you get about 2" deflection before it feels a lot stiffer. Masthead stays, if fitted, should be pretty soft.

Good conceptual explanation here:

http://www.tboat.com/Editorials/Edit-de ... t-rig.html
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Re: Mast tuning guide

Postby i550sailor@aol.com » Tue Jun 16, 2015 4:01 am

How many pounds are you setting your uppers, mids, lowers ? reading the setup guide there is not that many pounds on the uppers. Setting up my rig yesterday the mast looked pretty good with the mids set at 280#'s
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Re: Mast tuning guide

Postby Chad » Wed Jun 17, 2015 12:15 pm

Yep, may basic tune has 300# on the mids. Spreader length and chainplate angle and width will be different for many boats. Use your forestay deflection as the guide for how much overall tension, and your mast bend to set the relationship between mids and lowers.
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Re: Mast tuning guide

Postby i550sailor@aol.com » Fri Jun 19, 2015 4:28 am

How about the rest of you guys,,, what do you have your rig tuned to?.
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Re: Mast tuning guide

Postby jray » Fri Jun 19, 2015 2:58 pm

I haven't bought a gauge yet. I set up for 5 to 6 inches of pre bend and go sailing. A gauge probably be a good investment this spring.
Jon
#061 Critical Twist
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Re: Mast tuning guide

Postby i550sailor@aol.com » Fri Jun 19, 2015 3:23 pm

jray wrote:I haven't bought a gauge yet. I set up for 5 to 6 inches of pre bend and go sailing. A gauge probably be a good investment this spring.


What I have always liked about a gauge, is repeatability, to find that sweet spot in your rig/sails, and be able to repeat those settings for the conditions you are sailing in.
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