GNAV

[Duncan Adams]

Hi All,
I am about to fit a GNAV system to my tin rig Viper, I have quite a few of the bits I need but I don't have all the measurements. Can anyone tell me the following:
The measurement from the dec to the top GNAV fitting on the mast?
The length of the GNAV tube?

Thanks
Duncan

[Dave Nickerson]

Duncan - I'll try to get you the measurement off our carbon mast tomorrow.  I was thinking the distance between the 2 gooseneck fittings is the best I can do since the mast is out of the boat.

The length of the tube is in the Class rules, section 6.4: The length of the tube (without end caps) shall be 122 cm +/- 6 cm

Has anyone put a GNAV on a Viper tin rig before?

[Ben Steinberg]

the goosnecks measure 39" center to center. 

[Darren Gilbert]

The Boat I just bought came with a Tin rig and I've been thinking about the GNAV upgrade.  My question is how do you fee the sail through the mast track with another goose neck on it?

[Greg Jackson]

The Boat I just bought came with a Tin rig and I've been thinking about the GNAV upgrade.  My question is how do you fee the sail through the mast track with another goose neck on it?

You'll have to grind and file or mill a new feeder above the gnav gooseneck and add velcro to the sail to connect it to the mast below the gnav gooseneck.

I did the grind/file trick to a replacement Lido 14 mast five or so years ago...

[Duncan Adams]

Thanks for the measurements.
We have a top fitting that rivets on to just one side of the mast so no need to change any sail feeds. Bit concerned by the strength of the fitting but there is only one way to find out if it's gona work, and if it breaks shouldn't do much damage???

[Tim Carter]

if it breaks with the kite up in breeze you my say good-by to the rig...  =:0

[Ben Steinberg]

I know the fitting you're talking about, its cast stainless.  selden spec'ed it for vipers when they tried to get into the boom/gnav game.  It will likely work, but to confirm tims thoughts, sailing with a tin rig is sailing on borrowed time. 

[Duncan Adams]

Thanks for the tip. We have moved the shroud chain plates out, we also ploughed into a wave last saturday from 17knots with main out and rig stayed up so I hopeful it won't all come crashing down, either way it's insured?!

[Lee Shuckerow]

Thanks for the tip. We have moved the shroud chain plates out, we alsoploughed into a wave last saturday from 17knots with main out and rig stayed up so I hopeful it won't all come crashing down, either way it's insured?!

finally had our viper carbon rig payed for. It broke in February. Make sure you have a racing package on your insurance, takes care of rig, sails, and shrouds.

[Jay Harrell]

++1 on the insurance.  The day after we arrived home from 2008 NAs, a microburst hit our house and dropped a tree right on top of my mast, crushing it, and doing $10k of other damage on my house and property.  Insurance bought me a new mast...

finally had our viper carbon rig payed for. It broke in February. Make sure you have a racing package on your insurance, takes care of rig, sails, and shrouds.

[Justin Scott]

A very timely microburst if I remember.

If my damn keel box doesnt stop leaking I sense a micro burst coming on.

[Matt Sole]

Who are you guys using for insurance??

Finally Justin is realising there may be foul play in his keel box issue.

I point the finger at Lee and Brad......

[Jay Harrell]

Who are you guys using for insurance??

The Gowrie policy through US Sailing.  (http://www.gowrie.com/)  I owe them about 10 years more premium to break even.

And yes, it was well timed as far as the Viper goes - I got a new class mast out of the deal.  Despite the damage to the house, we were very lucky -  giant trees  (one 8 feet in diameter) fell all around both our cars, the Viper and our camper without damage, except for the big hole in the driveway.  Had the Viper or my truck been in their normal parking spaces, they would have been crushed flat.

[Brian Bennett]

FYI. Tin rig owners.

I would be very weary about installing the GNAV on the metal mast. Due to the shallower spreader angle, and narrower shroud base, also further forward than the Carbon rig geometry, you will have very little forgiveness in "breeze on conditions" The GNAV loads the mast quite differently to the regular vang, with much more distortion in the lower panel (deck to spreaders).

Additionally, by the time you file away the sail track, and add the compression gooseneck, you will have no material support.

I hope this helps. I have some new tin rigs in storage at Hall, if someone gets in a pickle. They will be cheap.

Regards,  Brian Bennett
Viper 640 designer