Elements affecting pointing ability in order of magnitude?

Aug 2, 2010
502
J-Boat J/88 Cobourg
Just thinking about the recent thread on struggling for speed on close reach and enjoying all the answers. Clearly some boats will point higher than others and then there is a further division to those that point better at different wind speeds. Off the top of my head, here are some of the factors I know about in no particular order in a list. I would love to read what others I should add to the list and/or your thoughts on their ranking of importance. Top 3 are boat design elements, next three are boat property elements, last ones are trim specific to wind conditions:

-keel depth and type
-jib sheeting angle
-hull shape/design

-sail condition
-hull but especially keel and rudder smoothness
-Rig tune

-Draft position from luff tension
-Twist
-sail draft depth
- forestay tension

This probably won't be as good a discussion as those prompted by Don's questions but I thought I should help out somehow for all the joy I get reading the responses.
Dan
 
Mar 26, 2011
3,399
Corsair F-24 MK I Deale, MD
  • Rudder design. Includes spade vs. skeg, shape, depth, area, and end gaps.
  • Amount of weather helm placed on the rudder (obviously adjustable) and the ability of the rudder to convert that into lift. Watch the angle.
  • Keel trailing edge. Should be narrow and squared off. Rudder too.
  • Mast rake (part of rig tune)
  • Prebend and relation to sail cut (part of rig tune)
  • Mast rotation, when applicable.
  • Sail area (won't point if over or under)
  • Weight. Over weight is bad. Aloft or at ends is worse.
  • Sea state, obviously.
 
Jan 1, 2006
7,039
Slickcraft 26 Sailfish
I'd skip talking about design, keel and jib sheeting angle since they are pretty much given for a particular boat. I'd rather focus on the things you can control. So, I'd put rig tune as #1. If you rig tune is off the sails cannot perform as designed. I'd have to put good sails at #2. If you want to move up in the fleet by pointing better buy good sails. #3 - don't dare go out and waste your good sails sailing with a dirty bottom. Sailor's Do It With a Clean Bottom! And to simplify the discussion I define a clean bottom as one that is smooth in the first place. It is impossible to clean a bottom that is not smooth. #4 - I would say is sail trim. Again, the sails just won't go if they are not trimmed to the wind and water conditions. #5 - Driver's ability. Some are naturals, others learn from experience, and there are some who will never be good. 6 - Weight. Lighter is faster and faster is pointy-er. That would be my list.
 
Mar 26, 2011
3,399
Corsair F-24 MK I Deale, MD
Sheeting angle is an easy change. Heck, you can rig in-haulers and out-haulers for testing purposes with stuff in your parts and contingency box. It is one of my more frequent adjustments; in to point high, out when I need more power or the wind is up.

Clean bottom might be number one, from what I've seen!
 
Aug 2, 2010
502
J-Boat J/88 Cobourg
Great answers Folks, thanks for the input. As for a smooth bottom, what is the best way to accomplish this? My bottom is fairly smooth with no wrinkles or lumps in the paint, but I am starting to have some rust problems on the bulb of my keel. Would you sand the existing paint smooth and then put the antifoul over the sanded area or do I need to take all the existing anti-foul off to the base and re-apply? She is now a 11 year old boat and the bottom paint is quite smooth so I would guess there is not much build-up.
 
Jan 1, 2006
7,039
Slickcraft 26 Sailfish
I gather you have an iron keel if the rust is really from the keel. There are SBO people would better answer your question.
 
Apr 8, 2010
1,942
Ericson Yachts Olson 34 28400 Portland OR
Even a little slime on the bottom will slow you down - more than you might imagine. Seems counterintuitive, given how "slippery" that stuff feels to the hand! :)

If you have an iron keel, it will have more cross sectional drag. Significantly more compared to a lead keel. :(
Dealing with rust is something that goes with ownership of a boat so equipped, no matter what the builder or broker mumbled when they brushed off the question.

If you are dragging a fixed prop, there goes another half knot, and a couple of degrees of pointing angle.
Sailing close hulled -efficiently- is where a lot of design and maintenance factors all come to bear.

Best of luck, and fair winds!
 
Nov 26, 2012
1,653
Hunter 34 Berkeley
Forget about the stuff you cannot control unless you are planning a career in sailboat design. Get the rig tuned. More mast rake equals better pointing but more weather helm. Good sails. A hank on jib that comes all the way down to the deck is better than a roller furled jib unless your furler is below deck. Moving the draft back improves pointing but is slower. Tighten backstay. Sheet boom to center and add a little twist at the top. Fair the keel. You mention a bulb on the keel. Is she a shoal draft boat?
 
Aug 2, 2010
502
J-Boat J/88 Cobourg
She is the shoal keel but it is the typical Beneteau bulb and she draws 5'. Better than two other shoal keel boats I have had but not a deep fin which I know would help.
 
Oct 19, 2017
7,732
O'Day 19 Littleton, NH
The rust may not be from an iron heel, but from rusting bolts, if the bulb is not a molded integral one-piece part of the keel. Look into that.

I would think the three most important factors in pointing ability are type of rig. Most of us are sailing marconi style. Tuning and balance of boat, and tenderness/stiffness.
Lots of small factors to improve this, of course, but those are what I have come to understand are the major factors for pointing.

-Will (Dragonfly)