Speed and Sail Trim.

[geehaw]

Last weekend I was out in about 20 knot winds. I weas sailing with a reefed main and a genoa. Heel was about 30 degrees and going to 40 from time to time. I did all the recommendations of Don's charts to keep it on its feet. But heel did lessen but so did speed. I was lucky to get 3 knots at 20 degree heel. So weather helm was a bit strong when heel got larger so I put the working jib on heel was about the same weather helm was improved speed was down. Pointing was better but not much.

Day before sailing in 15 knot wind with Genoa and full main tacks were about 88 degrees, I was pretty happy with that, the following day with the higher winds a 45 degree tack with either jib was the best I got. I have an Oday 25 shoal keel. New main, fairly crisp genoa, maybe a 130, and an older but not totally blown out working jib.

Now Stu has mention here that a loose forestay can make a cranky boat. So I am wondering if this could be my problem? Boat sails great up to about 20 knots but after that it just don't sail well. Oday's manual says hand tight plus 2 turns on the turnbuckles. So what does that mean? (Rhetorical question) I have Johnson barrel turnbuckles and if I was to do that the stays would still be flapping around loose. So I use a Loos Gauge and use the lowest setting on their chart for the size cable I have. So I guess my question comes down to is: Can I tighten the forestay more with out damage to the boat? I realize this can depend on a lot of things but lets say everything with the rigging is ship shape. And is there an easy way to determine if the jib has to much bow in the luff. Greg

 

[shemandr]

I'll repeat what has been stated here before and many other places. Tightening the forestay is to set the rake of the mast - which affects weather helm to a great degree. But if you want to take out sag in the forestay use the backstay to put more tension on the forestay.
And, in 20+ kts. with a shoal keel you may not be able to expect much more. 30 to 40 degrees of heal is a lot. I would think you would do better to reef and flatten the boat. Let it get on it's feet and go. As it gets breezier pointing will suffer for almost any boat. And if you have waves you will need to foot anyway for power.

 

[Alan]

shemandr has hit the nail on the head. Forestay adjustment is EXCLUSIVELY to set mast rake. It is NEVER used to tighten anything. Sounds like your rig is too loose for the sailing conditions. Using the lowest settings on the rig is not a good idea. A good rig tune will keep the mast centered and taught in all conditions. Tightening the forestay is accomplished with shroud tension (on swept spreaders) and/or backstay tension. As the breeze pipes up the forestay should be made increasing tight with your backstay adjuster and sail shape increasingly flat. Puffs are dealt with by dropping the traveler and depowering the tops of the sails.

 

[geehaw]

I understand what Shemandr is saying. My shrouds are not swept back nor do I have a back stay adjuster and Odays 25's are masthead rigged. Mast rake was set awhile back so now tightening rig with forestay or backstay would not cause any appreciable difference in rake I would think. But since I have a trailer sailor and the backstay is taken loose to drop the mast I will make adjustment there if I decide to do it. Which I will next time the winds pipe up. Thanks Greg

 

[Don Guillette]

Here's why mast RAKE (not mast bend) affects weather helm The boat thinks you've picked up the mast and moved it aft and reacts with weather helm. I think the Hunter boats, because of their rig, react differenty to mast rake but boats with a "telephone pole" for a mast react with weather helm. Alan, good to see you back on the forum. Am I right about the Hunters?

There's nothing wrong with a little weather helm but too much is not good for me.

 

[geehaw]

I went back in the archives and found a thread by Rich H on sail luff hollow. This described my symptoms to the tee. So I think I need to try and tighten the rigging. There was a lot of bow in the forestay. Boat sails great in the 15 knot range its just once I get into the higher winds I have the trouble.

 

[RichH]

Over tensioning the jib sheets can also mimic a too loose forestay (backstay). Such can cause an increased sag in the forestay .... Which causes the jib to go 'draft-aft' and the boat to skid off to the lee.
With a shoal keel your probable biggest concern is a skid off to leeward, so you have to keep a good eye on the stern wake to tell you if its a skid or just increased so-called weather helm. If that stern wake is coming off at noticeable angle when you have 'increased helm pressure' it's not weather helm, it's SKID to leeward.

PS .... At least for 20 kits. Start with the backstay at 20 per cent tension

 

[scott754]

I have owned both O'day 25 and 30 and found they lose speed after 15 degrees heal.

 

[geehaw]

RichH I was watching the wake from the boat in the lower winds and no signs of side slip however I don't remember if I looked in the higher winds. I have been keeping an eye on side slip because of other posts you have made about it. It might be side slip though, as wind on my face and wave direction told me I should of had a better tack angle. But just could of been my lack of experience.

Over tightening the sheets is very possible since I was trying to get the jib in tight to improve pointing. It was still a long ways from the spreader, maybe 8". Is this a situation where a barber hauler would help?

Scot 754: Your right its a a fairly fast boat till ya get it past 20 degrees of heel.

I must thank you all here for your help. In 3 short seasons you have helped me go from "OH MY GOD I GONNA TIP OVER"!!!!! To "Wow 40 degrees of heel this is wrong what do I do to fix it". So would a Barber hauler maybe help? Greg

 

[Alan]

geehaw, if your sheets are in tight and the genny is still 8" off the spreaders then it may well be your car location is well off. In 20kts you should be able to pull the sail to the spreaders or at least within an inch of them. You may want to consider moving the cars aft a little at a time and re-trimming till the luff starts to flatten out a bit more.
...but back to the forestay and mast rake. If you do not have a dedicated backstay tensioner, many guys don't, you would take up more tension on the backstay turnbuckle which will tension the headstay without changing the mast rake. Moving the masthead forward will decrease weather helm but it will also cost you pointing ability and can even take away a small weather helm to make it lee helm (which is very bad)
Don, thanks, good to be back. Yes some Hunters do have smaller section masts and being most of them are fractional rigs they make it easy to 'bend' the mast for sail shaping (except those &%#@* roller furling things). Masthead telephone poles must rely on a less adjustable rig and a backstay adjuster, IMHO, is a must have for these boats.

 

[Scott T-Bird]

I agree with Alan that the backstay adjusted is must have for a masthead rig. Pointing improves and the rudder becomes much lighter when it is adjusted correctly for the wind condition.

 

[RichH]

Over tightening the sheets is very possible since I was trying to get the jib in tight to improve pointing. It was still a long ways from the spreader, maybe 8". Is this a situation where a barber hauler would help?

In the higher wind ranges, the barber hauler 'goes out' in order to "open the slot". The distance between the mainsail and the jib's leech if held 'close' as when sailing in 'normal' conditions will 'choke the slot' with a too high wind velocity in the slot which can cause adverse boat/sail performance. A simple easing of the jibsheet (watching the distance of the jib leech from the spreader while watching the speedo/VMG) a bit OR moving the fairlead car more aft is the minimum/easiest correction to get the 'best' slot distance.

Be mindful also that in stronger wind, your sailing angles on a beat will be much less than when in 'normal' winds all due to the 'relativistic' changes between the apparent wind and speed of the boat; and also, the 'natural tendency' in the higher wind ranges is to 'pinch up'.

The simple solution in higher wind speeds is 'increased backstay tension', not over-tightening the jibsheets (for slot control, and not artificially inducing 'sagging the forestay' via the jibsheet), and keeping the boat 'upright' as best as possible. Of course with a shoal keeler, you do have reef 'earlier' and that alone will help the boat to 'stand up'.

;-)

 

[Stu Jackson]

All of this advice is very good. We must, however, remember that it appears that the OP may not have all the bells & whistles we all may have added to our boats as we learned about sail trim over the years.

I sailed our Catalina 25, similar to the OP's O'Day 25, without a backstay adjuster for a few years on our high San Francisco Bay summer winds. Once I realized that our closed body turnbuckles were a disaster waiting to happen, and re-did our standing rigging, I stayed (NPI) with it.

Once I re-rigged with a Johnson backstay split tensioner with a simple backstay vang tightener, the forestay got a lot tighter when I wanted it to.

I think "That's the trick."

Sounds simple, but take a long time to make it seems like one of those "Why didn't I think of that!" things.

Good luck.

 

[harv]

Here's why mast RAKE (not mast bend) affects weather helm The boat thinks you've picked up the mast and moved it aft and reacts with weather helm. I think the Hunter boats, because of their rig, react differenty to mast rake but boats with a "telephone pole" for a mast react with weather helm. Alan, good to see you back on the forum. Am I right about the Hunters?

There's nothing wrong with a little weather helm but too much is not good for me.

Re: Hunter boats- I assume you are referring to the B&R rig. Why do you feel that Hunters react differently to mast rake? Do you think that it is because of the small jib and large main that the Center of Effort in relation the Center of Lateral Resistance can't be significantly changed by mast rake? Sort of a catboat phenomena.

 

[jmallard]

I have just completed the Competent Crew Sail and the Day Skipper Sail certification prgm with an ISPA instructor in Comox, BC. It makes sailing so much easier to learn from a pro on a boat, on water. The instructor was able to demonstrate and teach me anything I wanted to know, and correcting bad habits, about safe sailing in a multitude of situations. I highly recommend these courses to anyone who want to learn/improve their sailing skills, including sail trimming.

 

[RichH]

Another possibility ... is 'weak' sail material in the mainsail, sail material that unduly stretches especially in the higher windranges.
When such 'inexpensive' woven dacron is under tremendous load the fabric can and will 'stretch' and with respect to so-called weather helm that stretchy fabric will result in the point at where the point of MAXIMUM amount of draft will move aft in the sail. That rearward movement will most definitely induce 'weather helm'.

The solution: tighten the mainsail Halyard to bring the point/location of maximum draft forward. Alternatively if you have one, now is the time to tighten the 'cunningham' - the best way to visualize such a 'shift' in where the maximum draft occurs is with a 'draft stripe(s)' on the sail.

Adhesive backed draft stripe: http://www.sailrite.com/Draft-Tape-Black-1