The collar
A ring, not a hole in the head
People point at the shiny band and call it the hosel. The hosel is the socket. The ferrule is the collar that dresses the joint. We live on that thin cylinder — how long it is, what color it wears, and whether it still sits after a wet week on Lake Erie.
Cross-section
Inside diameter, outside, and the fillet
Look at a ferrule the way a glass inspector looks at a rim. There is an inside diameter that has to hug the tip. There is an outside diameter that has to meet the hosel paint without a step. There is a length that either hides the epoxy or advertises it. After the head is on, a small fillet of adhesive can creep. We wipe that fillet while it is still plastic, not after it has skinned.
Cheap nylon arrives oversize on the ID and undersize on the OD. Installers heat it, shove it, and hope. Hope lasts until August humidity on the Maumee. Then the ring swells, the paint line crawls, and the golfer thinks the head is loose. Sometimes the head is loose. Often the collar is just drunk on lake air.
Materials on the rack
Nylon drinks. Aluminum does not.
Nylon stock
Most collars on modern irons are nylon. It turns cleanly on the lathe and takes a polish. It also takes on water. We keep nylon in a sealed cabinet with a humidity card. If the card has gone pink, the stock does not go on a gamer. Outdoor pegboard ferrules from a big-box bin have already lived a weather life before they ever see a tip.
Aluminum and mixed metal
Some woods and a few putter necks wear a metal collar. Metal does not swell the way nylon does, but it shows machine marks and it can gall a painted hosel if the OD is proud. We turn metal slower, with a different tool, and we test sit with a dry mock before epoxy. Color on metal is anodize or paint, not a dye-lot stripe.
Sit
Proud, shy, or flush
Flush is the only sit we will sign. Proud means the ring stands above the hosel — a length miss or a head that did not fully seat. Shy means the epoxy fillet is the only thing filling the gap, and fillets yellow. We measure existing sit with a small square against the hosel shoulder before we cut anything. That number goes on the ticket, next to the color code.
A longer collar does not add distance. It can change how the neck looks in a photograph and, in a few builds, a gram or two of mass at the joint. If you want mass, say so. Do not ask for a longer ring as a secret swingweight trick. We will tell you it is a weak trick.
The room
Lathe, cabinet, and the color drawers
Suite 8 is one room with a window on Superior Street. The lathe sits on the river side so the motor hum is not aimed at the hallway. Color drawers are labeled by decade, not by brand slogan. A 1980s amber band lives in a different tray than a 2010s gloss black. Corinne will not mix those trays because “they both look gold in the photo.”
You can stand at the glass and watch a turn. You cannot lean on the cabinet. The humidity card is not a decoration.