Author Topic: Tuning Forte Mast  (Read 1048 times)

Mike Reyes

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Tuning Forte Mast
« on: May 04, 2021, 07:05:57 PM »
Any rig tuning tips for the Forte carbon rig? I find tuning guides for the aluminum rig, but have only guessed for the Forte shroud tensions. 
Mike Reyes
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Mike Josselyn

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Re: Tuning Forte Mast
« Reply #1 on: May 08, 2021, 11:36:57 PM »
Alas, no tuning guide.  I decided to make my own by setting up the rig at a base tension and then using a Loos gauge and measuring tape from the top of the mast to the transom. Be sure the rake of the mast as measured to the bottom of the transom at base tension is within class specs of 34.9 to 35 ft.  I developed a chart by increasing the tension on the upper shrouds (I generally keep the lowers just tight enough to keep the mast straight) and measuring the distance (decreasing) between the top of the mast and the transom.  I also measured the increasing tension in the forestay. 

I now have a chart of the mast bend (and forestay tension) for my dyform rig under various shroud tensions (important to have calibrated tensioners).  Using that I have tested the tensions I use under various wind conditions and then developed the numbers on my shroud tensioners that I use for various predicted winds prior to the race.  They are likely to be different for each set up (and even sail loft) but here is what I use:

Base: 1.5
1 to 4 1.75 to 2
4 to 8 knots 2.25 to 2.75
8 to 15 knots 3 to 3.50
Above 15 knots. 3.75 to 4.25

Forte mast generally requires more tension than on the Al rig.  Greatest change in bend at lower tension settings and then flattens out.  Same with forestay. 

Iím sure one could play with lower shroud tension as well but I find these work for my conditions on SF Bay.

Always interested other approaches. 

Mike

« Last Edit: May 17, 2021, 12:56:49 AM by Mike Josselyn »

Mike Reyes

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Re: Tuning Forte Mast
« Reply #2 on: May 14, 2021, 12:09:19 AM »
Thanks Mike. I'll  play around with your settings!
Mike Reyes
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Mike Josselyn

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Re: Tuning Forte Mast
« Reply #3 on: March 17, 2022, 05:15:50 PM »
I have done a bit more refinement to the tension settings for the Forte mast on my boat as well as recommended tension for wind speed.  I used a conversion chart for the tension because I have dyform rigging.  Mast bend is an indirect measurement by running tape up to top of mast and measuring decrease in length to base of transom.