Vibration
I also get a vibration from under the boat when she's clipping along. Release the tension on your keel cable.Raising my mast is done on the trailer with my mainsheet on the forstay. I throw the forstay over my shoulder, as a bystander to hank on the mainsheet which is hung off the bow of the boat and up the mast goes. Lock the mainsheet in the cam and set the boat up. Catalina Direct also sells a new device that is supposed to help out, don't know if I want to spend the money on it or not. My kids 12 and 14 are still enchanted with sailing and I don't get to sail alone much these days."Windsocket" 2226