All
I have used a couple of propriety rudder systems lately, some I have bought and two were with a Model Slipway Tamar kit. I have had a problem with the threaded tube that fits to the hull, the thread that the large brass nut goes on doesn't go down to the base of the tube, so on the Tamar I have had to add a spacer made from a small section of plastic tube, to get a seal to the boat hull. I have just bought two more sets and they have exactly the same problem.
Am I missing something I don't think I have had this problem until building the Tamar.
Tim