New owner of #129

[Peter Beardsley]

Mainsheet setup is definitely all about personal preference.  Good arguments can be made for aft sheeting or center sheeting.  Some of those arguments can be found at http://forum.viper640.org/sailing-handling-tips-and-techniques/technical-committee-announces-new-test-of-stern-bridle/msg19868/#msg19868

That is otherwise a lot of vang tension - tracks and stoppers are not always in the same spot, but if you're able to hit the front stopper, you're probably using too much vang and are at risk of breaking some hardware (gooseneck and boom mostly - boom would be more rare, but we've definitely seen people break goosenecks and I think I've seen at least one broken boom before, exact cause I am not sure).

Changing mast blocks while racing: 

1. Don't do this upwind unless you're removing blocks.  If you're adding blocks, it means you're overpowered, and to change blocks, you need to take people off the rail, which you don't want to do if you're overpowered, so...

1a. It would need to be a pretty big change from too windy to too light to want to remove blocks while sailing upwind and you'd want to be confident that the breeze wasn't coming back on that leg of the course.  This is not something we do glibly on 269. 

2. The main reason we do this is because our rig is out of whack and mast block changes mid race are only a temporary fix.  We're not allowed to change upper or lower shroud tensions mid race so this is the best we can do. 

2a. Example: Race 2 of 2019 Viper New Englands two weeks ago: started in 7 knots of wind and we had 2.75" of blocks in or so and we were around 27 or so on our upper shrouds.  Within 2 minutes after the start we were fully hiking in 12-13 knots of wind with our upper leeward shroud flopping around and lots of headstay sag.  Woops.  That is suboptimal since as mentioned above, the headstay sag made our jib too full and we were overpowered.  To deal with being overpowered, one thing you can do is ease your main...which causes you to sag your headstay even more and continue to power up your jib (to a point).  Double whammy.  So then you need to ease your main EVEN MORE to keep the boat under control...and by then you need to ease your jib since now you've closed the slot from easing the main out a few feet, and then with your sails cracked too hard, you're barely going upwind anymore (at least compared to the leaders). 

Since we couldn't tighten the rig, we used every other depower option upwind first - outhaul, cunningham, jib halyard fine tune, jib leads aft a couple of holes, vang on, sails cracked a tiny bit (more jib than main so that we could keep the headstay tension on), feather a bit more than we might otherwise like to keep heel angle under control, hike hard and suck it up for a bit.

When we turn downwind:
1. Kite up
2. Figure out where you want to go.  If you want to gybe, do that first.  If you want to roll someone, do that.  Don't lose sight of the bigger picture.  But if you want to go straight and are able to do so for 60 seconds without getting rolled...
3. Have the forward crew loosen up the mast block line and get everything queued up - blocks above deck if they were hanging low, etc. 
4. Pass the spin sheet to the driver
5. Middle crew pulls mast aft as described in prior post, forward crew jams in blocks (or removes blocks quickly)
6. Driver passes spin sheet back to middle crew while forward crew cleans up and tightens up the mast block line

We've found that every quarter inch of mast blocks that we add after 2.5" of blocks adds about 1.5 numbers of Loos gauge tension-ish.  So adding blocks doesn't usually get us to where we need to be, but it'll make things less painful for the second beat - we'll still usually need to get the shrouds aligned once we finish so that we're fully set for the following race.

If we're not sure about where we want to be with shroud tension / mast blocks going into a race, we tend to leave some mast blocks out (whether it is 0.25" or 0.50"), and we set the shrouds appropriately for the wind conditions that we have at the time, MAYBE a touch loose on the shrouds by half a turn.  Thought being that since we can't touch the shrouds but can add / subtract blocks, if it gets windy we can add blocks during the sequence or on the first run and be pretty close to where we want to be, or subtract blocks and also be pretty close. 

Most teams aren't messing around with blocks during a race so we know that if we have this in our back pocket, we're going to be able to extend on the second beat and that is a nice confidence boost for when we're hiking to overcompensate on the first beat. 

[Justin Scott]

A note of caution for newcomers to the class.

You are sailing a carbon mast with no backstay.  These masts will break in big breeze if you dont observe a few  basic and commonsense best practice guidelines.

The following factors increase the risk of breaking your mast sailing downwind. None of them individually will cause the mast to fail but until you perfect your technique they are items to be aware of

1. You increase the stress on the mast the further aft you place the mast (ie max headstay length and max aft in the mast step) because you reduce the angle that the uppers are holding the mast in column.
The best position for tune is max length headstay. If you have to make any tradeoff, having the mast butt one hole forward is better than shortening the headstay.
Shortening the headstay in big breeze improves the angle that the uppers are pulling back on the rig (and can allow the uppers to apply more tension to the headstay) but the disadvantage is that it reduces mast rake in big breeze which is not fast. I dont know what Brad does if he shortens the headstay but I would contemplate also moving the mast step one hole forward to preserve rake.  We have not tried this.....but if you move the top of the mast forward, I would move the base of the mast forward as well. 

2. Not enough tension on uppers in big breeze, puts the mast at risk downwind.

3. Too much tension on lowers in big breeze, puts the mast at risk downwind (holding the lower half of the mast "back" means that the top half of the mast is taking all the stress.....visualize how easy it is to break off the tip of a carbon fishing rod if the hold the top in both hands versus allowing the whole rod to bend)

4. Too much chocking down low puts a mast with too little upper tension at severe risk. Same as #3 above, but too much chocking can create reverse prebend and sets up mast inversion.

5.  Easing out the mainsheet too far, losing the leech tension that is holding the mast in column.

6. Easing the Gnav too much, losing leech tension.

The best protection for the mast is max tension on the uppers and keeping the mainsheet and boom end close to the boat.

I mention this because if an owner has : Mast max aft,  only 27 Loos on the uppers  and a big breeze comes up.......then going to max chocks aft at the partners downwind  sets up a high degree of risk for the mast.  It means one of two things:
1. The owner also owns stock in Superspar
2. The team is very skilled and adept at keeping the rig in the boat. They need to be watching the headstay like hawks downwind and putting the gnav on hard if they see it going overslack.  They will have the main sheeted in downwind with the boom end close to the transom corner and doing jibes with a fair amount more vang than normal ....blow through gybing smoothly to prevent broaches and avoiding a snap tension on the mast coming out of the gybe.
Unless the race result is worth $4,000+ , a newcomer needs to exercise a considerable amount of caution if they are caught out in big breeze with low tension uppers......to finish first, first you have to finish!

Enjoy.

[Gary Annino]

undoubtedly me but how do I get to see the pictures?

[Gary Annino]

yep - it was me.

ignore

[Bill Vickers]

   Peter et al this was a very helpful post for us since we were sailing our boat for the first time in Noroton.     
     We have tried easing the Max headstay length 1-2 cm beyond the North sails guide but didn't notice much a difference...this was only in practice though in puffy conditions fully hiked.    It seems extending the headstay a few cm might be helpful (it is in some boats) but perhaps the very flexy top section of the Viper and no backstay negates this affect.   We will try it more though and possibly have to move the mast step forward though....screwing up all the mast block measurements and shroud tension numbers. 
   We were sailing slightly heavy in Noroton and had difficulty upwind and holding lanes off the line....but remembered this post and started taking out blocks and by race 2/3 we were a bit faster upwind allowing us then to start playing the shifts.    Since we were heavy,  we needed alot of headstay sag.   We certainly lost some pointing ability by doing that and were down to 2.25 " blocks for a period time on Day 1 with 25 Loos on the Outer shrouds, and especially Day 2 when the wind was lulling at around 8 mph.... until our prayers for more wind came true.  Since we were having to foot everywhere with alot of headstay sag, we tried winning the pin end a number of times or searching for big holes using a port approach.   
    We tried changing blocks on the upwind but just wasn't possible with the load from mainsheet.   
Wasn't too hard to do on the downwind though but the 1 person struggled with it.     We are a beginners to the Viper but epoxying in the front block (or perhaps just velcro) and only changing out the middle blocks makes alot of sense...so we may consider that.   It's pretty tough getting in the new block under tension even with 2 people.  Was thinking a short 2:1 block system around the mast at deck level to the keel lifting eye might make it easier for 1 person to do.   Wondering if anyone has tried this.
    Viper is really a wonderful boat to sail...even compared to the foiling craft I've been frequenting of lately. 
    Those experienced with racing in Noroton, it was difficult to ascertain benefit of sailing more inshore on the incoming tide.  Fleet by in large played the middle.    We were wondering why more weren't favoring a side....perhaps we were far enough offshore and the upwind too short that it didn't matter ?

[Peter Beardsley]

     We have tried easing the Max headstay length 1-2 cm beyond the North sails guide but didn't notice much a difference...this was only in practice though in puffy conditions fully hiked.

Guys, odds are good this wasn't legal - the North guide recommends the headstay length be 7588mm - which is also the max length allowed under the class rules.  There are times when all of us may want longer headstays but class rules prohibit anything longer than 7588mm presently - definitely doublecheck that length before going to the next event with your boat.  See Class Rule 5.1. 

   We were sailing slightly heavy in Noroton and had difficulty upwind and holding lanes off the line....but remembered this post and started taking out blocks and by race 2/3 we were a bit faster upwind allowing us then to start playing the shifts.    Since we were heavy,  we needed alot of headstay sag.   We certainly lost some pointing ability by doing that and were down to 2.25 " blocks for a period time on Day 1 with 25 Loos on the Outer shrouds, and especially Day 2 when the wind was lulling at around 8 mph.... until our prayers for more wind came true. 

That's a pretty light setting, but there was enough chop last weekend to make it work at times.  Still, we never go below 2.5" of mast blocks. 

    We tried changing blocks on the upwind but just wasn't possible with the load from mainsheet.   

That, and unless you were able to keep the boat flat while doing it, you're taking people off the rail at the wrong time usually.  Unless we are at something less than max blocks, moving blocks for us is usually a 2-person job.

It's pretty tough getting in the new block under tension even with 2 people.  Was thinking a short 2:1 block system around the mast at deck level to the keel lifting eye might make it easier for 1 person to do.   Wondering if anyone has tried this.

Paging Dave Nickerson, but probably not legal unless you wanted to use the actual keel lifting purchase - remember the fundamental Viper class rules in 1.4 and 1.7 - can't alter equipment unless specifically authorized by the rules. 

    Those experienced with racing in Noroton, it was difficult to ascertain benefit of sailing more inshore on the incoming tide.  Fleet by in large played the middle.    We were wondering why more weren't favoring a side....perhaps we were far enough offshore and the upwind too short that it didn't matter ?

WLIS doesn't have a lot of tide relief for Viper racecourses - if you sail closer to shore in smaller boats there can be more of a difference.  That said, I thought that on Sunday the left was favored upwind - whether that was relief from the flood tide, a geographic shift with the parallel shore, a bit more pressure, a bit of relief from the chop from the easterly, or all of the above, there were definitely a few times when teams sailed around us who hit that corner hard.  Still a pretty good effort by Rachel in her first Viper regatta as a skipper (and first non-Sunfish regatta!)

[Bill Vickers]

    Thanks for the input.    Thus far we have been practicing with the headstay at 7580 and have tried up to 7600 getting to understand the boat.  Mostly regarding we sail the boat heavy thus far while we are doing Keto diet and diet coke with our rum to lose weight,   and we were curious how it would feel with the mast butt more forward and going up to 7588 and even further.    Our boat certainly tends toward lee helm lock with being shorter than 7580.   Since the rules prohibit moving the mast butt during a "regatta" it's likely a mute point anyway. 

    Mast block removal:     
 
    Dave, was wondering about taking the mast chock line back around the mast to the keel lifting eye or whatever that lines is called....as it's released anyway when changing blocks and creates an easy 2:1.   Seems ok per the rules since it's part of the boat.    Stepping on the cabin console to put in the blocks with 2 people like we were told flexes the deck quite a bit, but my guys should be Starboat crew :) 

[Bill Vickers]

Carson, don't mean to be extending this thread into another direction....


But....Dave and someone tell me what this exactly means in terms of Forestay Length measurement point to help me figure out "The questions that bother me so"      Jimmy Buffet

Getting differing opinions of this and what it means

"The length of the headstay shall not exceed 7588 mm and shall not be less than 7512mm measured from the bearing point of the upper tang to the bearing point of the lower attachment point."   

Is this undersurface of the T tang to the top of the clevis pin ?

And it's way too cold outside for November


Bill

[Carson Downing]

According to Defender.com... So that would mean the center of the forestay pin on bottom? I'm sure a member of the TC could verify this.

[Carson Downing]

Picked up a CNC over the holidays. Fresh mast chocks anyone??

[Peter Beardsley]

Nice work.  Does the mast chock that meets the mast have a 7 degree angle or so, or is it straight?  http://forum.viper640.org/repairs-maintenance-and-upgrades/mast-chock/

[Carson Downing]

Yep, 7 degree bevel for the mast. Theres a half inch of material in front of the mast, .75'' total thickness. I could also make these in any shape and thickness up to 2" thick.

[Matt Rowlinson]

oooh--sweet! Can I ask how much for a set, or even just for the one by the mast?

[Carson Downing]

How soon are you needing one? I haven't made any other pieces yet, but was thinking:

1- 1" piece
3-.5" piece
1-.25" piece

That would bring the total up to 3.25" with the curved front chock.

[John Leyland]

I'm interested as well.
Thanks,
John