Weather helm

[yacht371]

Years ago a client complained of extreme wether helm on his Roberts 36 (log keel, attached rudder. Before I even looked at the boat, I asked what type of prop it had. It was a large wide 3 blade fixed prop. I advised him to fit a Campbell narrow 2 blade prop and line it up behind the deadwood when sailing. Problem solved.

Other causes of weather helm (easily fixed) are:
Mainsail too full (jib could also be a problem)
Loose rigging, sagging forestay
Rudder too small or poorly shaped (should be tapered, thing after edge with sharp corners. Thick trailing edge with rounded corners is common on home built boats.
No main traveller or vang. When beating in strong wind the boom should be over the corner of the transom, and the sail vanged down tight, halyard tension or cunningham applied to flatten main.

If some of this sounds "racy" it isn't surprising. The same things that make a boat go faster, particularly upwind, also reduce helm unbalance.