@IslandFarmer:
Ahn, well, Rule #1 of sailing is: "Don't Argue with your Mother!" All kidding aside, glad to read that you and she shared a sailing trip, that's rare and very special. If she wants to sit on the low side, then let her, of course! And great that she's at the helm. If I may suggest for next time, make sure to counterbalance her weight (when she's on the lee side) by sitting out on the rail (far edge of the boat) on the high side (windward), maybe even leaning out a bit. If you're sailing a boat with a coaming (small wall) around the cockpit, then sit on a boat cushion on the side decks, anyway get your weight out there, keep the boat as flat as possible.
For a fuller understanding of all forces involved, read this:
viewtopic.php?f=43&t=6280The 4th and 5th sections explain exactly what's going on with your weather helm - the center of effort (CE) from the sails is too far behind the center lateral resistance (CLR) from the hull and centerboard, making you "round up" to weather (weather helm). You do want it only a bit behind (slight weather helm is good!), but not a lot. One way of solving that is certainly to raise your centerboard, but you'd be counteracting the benefits of the CB when you most need it. Going to windward in a strong breeze, you need it all the way down to keep you from drifting to the side. A better idea would be to loose your mainsail a bit and trim (tighten) your jib, which brings your CE forward. (Note, flattening the vang with the main would also work, but is not the first, best option). Likewise shifting your weight forward will cause the CLR to go aft and the CE to go forward, counteracting lee helm... in other words, get Mom to sit as far forward as she can while steering the boat (you do have a tiller extender?) and then move yourself around to compensate for her not moving.
Now, in your specific case on the port tack - boat heeled way to far to the lee, due to Mom on the low side - you are running into another problem which is the hull's tendency to turn away from the direction it's heeled. In other words, you were making the hull sit in a way where it naturally wants to steer itself to weather, that's why you were seeing so much weather helm on the port tack only. Read here for more:
https://theewater.sailingacademy.co.za/ ... t-a-rudderAnyway, a good 12:1 vang is a great thing to have for many reasons, and is easy to set up. But it's not your first or even 3rd line of action for countering your weather helm. That being said, the fun of sailing is exactly in learning to make you boat go in whatever conditions, including immovable Mom. Enjoy your time together - and slack off the mainsheet a bit on the port tack!
Best,
Tom