thompsondockside.com

I'm a little reluctant to even bring this topic up, my intent is not to create contriversy but rather to form a common basis of terminology. I'm not posing as an authority on this... but In various posts I see what I call stringers identified as sisters. Likewise some confusion on keelsons and keels. As a starting point (not necessarely correct) allow me to propose "common" component names. Hopfully those with greater knowledge will chime in.
KEEL - on our larger Thompsons that is the outer part of the "keel structure" that caps the garboard planks.
KEELSON - the inboard part of the "keel structure" , the keelson on our larger Peshtigo Thompsons is a composite structure composed of the keelson plank ( board) and two sister boards ( sister keelsons)
SISTER - any member ( board, rib etc) that is attached or bonded along side of another principle member to reinforce, strengthen or widen that member.
STRINGER - any member other than the keel , usually structural, that runs longitudnally in the hull. Our larger Thompsons have two major stringers, installed about 18 inches off center on either side of the keelson

Your thoughts ???
Joe B

The "keel" is on the outside of the hull. Some folks here on this forum call it "keel cap." It's just plain and simple called "keel." Same applies to large ocean going ships.

"Keelson" is inside the hull. It runs the length of the boat. It is onb top of the keel. On wooden boats made by Thompson, T & T, Cruisers, etc... it is made up of three pieces of wood laminated together. Thompson of Peshtigo called it a "T keelson." The two pieces on either side of the center board are not sister keelsons. The three boards (four on my 1962 T & T 19 footer) are collectively called "keelson."

Thompson of Peshtigo used the term "sister keelson" to describe what most folks call "stringers." The sister keelsons are the two pieces of wood running the length of the hull, parallel to the keelson. On the lapstrake boats they might be 18 to 14 inches on either side of the keelson.

There is an "outer stem" and "inner stem." The outer stem is steam bent and butts up against the keel. The inner stem is made up of several cut pieces of wood.

These are all terms used by Thompson Boat of Peshtigo in their literature and in drawings from the factory.

Andreas