J/24 Speed Clinic with Mike Ingham

Posted by on Aug 3, 2019 in Tuning | Comments Off on J/24 Speed Clinic with Mike Ingham

Mike Ingham visited Seattle in mid-July and ran a J/24 tuning clinic to help us all get the most out of our J/24s. Notes from Carl Sheath and the crew of Tremendous Slouch are shared below. Thanks to Keith Whittemore for organizing the event and CYC for hosting a Saturday evening chalk talk that was open to all members.

Below are Carl and Team Slouch’s notes:

J24 Tuning/Coaching Clinic with Mike Ingham. Friday 7/12 – Sunday 7/14

Main Topics:

  • Rig Tune and Mast Butt Position
  • Light Air Performance
  • Crew Weight Positioning

Rig Tune and Mast Butt Position:

  • The goal was to develop a consistent and repeatable rig tune and mast butt position.
  • The j24 is a genoa driven boat, so if necessary, prioritize headstay sag over prebend if one has to be compromised.
  • Work with headstay sag first through shrouds before moving to mast butt and pre-bend. 
  • How do you create more forestay sag? Move mast butt aft.
  • With mast butt at base and rig at 20 outer, 15 inner using Model B gauge, should have 20-30mm forestay sag.

Mike’s 4 most important things on straight line speed:

  • Forestay Sag
  • Boat heel
  • Genoa trim
  • Main trim – stall top telltale 50% in wind above 3-4kts.  More mainsheet tension in the moderate wind range until top telltale stalls 50-60% of time or you’re giving away power and pointing ability. There is no reason to look at the main telltale in wind above 10-12 kts when we are easing the sheets, traveler down, backstay on, etc as it will be flowing 100% of time.

Notes from Saturday evening talk:

  • More mast bend – flatter mainsail.
  • Less mast bend – fuller main shape.  Tightening lowers shrouds also straightens mast and adds shape to the main
  • Headstay sag –   Draft goes forward with a saggy headstay, easier entry, more drag, so ease halyard to compensate if necessary
  • Tight headstay – fine entry, less drag, draft aft, so tighten halyard if necessary to compensate
  • Tighter halyard moves draft forward
  • New genoa – use much more scallops
  • Older genoa – few to no scallops

Light Air Performance: (This was based on flat water and wind 3-5 knots).

  • Set rig to have 30-40mm forestay sag. Shrouds should be lightest setting.
  • Have small “scallops”. 1 inch from forestay or ½ inch from cord between hanks. Should only be showing in middle of genoa luff. Top and bottom quarter no scallops.
  • Trim in harder on main – 5+ kts should be stalling top batten 50%.  Trim harder than we historically have.
  • Always get boat up to speed then focus on having “nervous” inside tell tales. Try not to make luff tap nervous.
  • Slouch had too much outhaul for light conditions.  Look at extra sail cloth curled to weather as one indication of too much outhaul.  This did not go away until the main outhaul was eased considerably.
  • Keep boat very flat and crew weight forward. Keith had crew member in front of shrouds and Keith was sitting next to winch, transom was by far the most out of the water.
  • Use Backstay earlier than we are used to – even before we feel overpowered. Backstay on BEFORE traveler down. Also, ok to have boom 1-2” above centerline in light air conditions.  Both Keith and Mark were above centerline.
  • If you get a puff that creates too much forestay sag, use backstay to pull mast aft and tighten forestay.
  • Setting genoa cars in light, go touch/touch then car one hole forward.
  • During tacks, reduce genoa earlier. At beginning of tack ease genoa sheet a few inches. Once main is starting to luff release genoa. Allows it to trim in earlier on new tack. Never let it back.

Flat water and DDW:

  • Consider flying the kite off the pole12-18” to avoid creating a hook near the tack of the kite.  This only works DDW or when close to DDW AND when in flat water. Use weather heel to assist with this. Do not keep easing to a curl DDW as you lose power.  Yes, check-in occasionally, but less often. Ease for projection, not flow.  Max projection is the goal.

Crew Weight Distribution:

  • Always keep boat as flat as possible. As pressure builds, hike as hard as you can. Then to backstay. Then to traveler, then to vang and vang sheeting.
  • Keith had crew member in front of shrouds, transom was by far the most out of the water. Helm always in front of traveler.
  • Upwind in light, one in front of shrouds, two at shrouds, three packed forward to #two, trimmer in companion way, helm against winch.
  • Downwind in light, one and two in front of shrouds, three next to mast, trim from companion way, helm weather side by winch.
  • As breeze picks up, one two and three moves aft. Trim on rail. Helm as far forward as possible.

Takeaways from participants:

  • Mike Realized that he has more experience in heavier air, Mike will focus on several specific changes to his light air racing set-up including going mast butt back earlier and further back than he has previously gone and will work with tighter sheeting of both the main and genoa sheets in very light air
  • Keith is more focused on tuning headstay sag as top priority and less on pre-bend.  Not abandoning attention to pre-bend, but less of a primary focus. 
  • Greater focus and understanding on crew weight positioning fore and aft (especially upwind) and perhaps having less focus on crew weight forward upwind.
  • Paying closer attention to vang tension off the wind (having top batten parallel to boom or perhaps slightly falling off, but never poked to weather).
  • New understanding and of wind flow over spinnaker when DDW as being top-to-bottom and the subsequent effect on spinnaker trim.  Specifically trimming for shape and max projection rather than avoiding stall.
  • Need for better communication between helmsman and crew regarding weight placement to find optimum balance between weather spinnaker projection and excess helm drag. I need to be better at communicate with crew (especially trimmer) which mode we are trying to sail in.  Need help from tactician as to which mode we will be in after the weather mark rounding.
  • If we will want to gybe-set – we should know this well before the weather mark to allow greater chance to set-up inside.  Also should know very early which gate we want.  Finally, should have the best idea of STBD lay-line traffic early including whether they are over-stood (so we can tack under and make it) or whether they are pinching and slow (so we should cross and tack above)
  • Helpful to make/keep recordings details of previous regattas with rig tensions, mast butt placement, sail trim details and winds/sea state, with comments.  Allows for greater interpretation of settings in various conditions and allows for greater repeatability.
  • Importance of not being casual with rig tension, mast butt, headstay sag relative to varying conditions.