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IOM Fin, Bulb, and Rudder

I finally received my new IOM fin, bulb and rudder today! It was shipped from Australia from Radio Sailing Shop. So far they look great, but to be honest, I'm not entirely sure what I'm looking at.

The IOM fin is long, thin, carbon-fiber, and very light weight. It only weighs 101 grams! This isn't the way it is in Vintage Marblehead or Star 45's.

The rules say that the fin and bulb together can only weigh 2500g. The bulb is currently 2533 grams and it will need to be worked a bit to get its weight down. I intend to epoxy coat it and then paint it as well, so that will add a small amount of weight. There are clearly some parts of the bulb that need to be cleaned up, but overall it's a very nice mold!

The rudder came with a piece of 4mm stainless steel shaft, but I'm going to use 1/8" stainless steel. 1/8" is 3.175mm and is plenty strong for both Marblehead and Star 45 rudder posts, so I'm pretty sure it'll hold up to this. 1/8" stainless rod fits perfectly into a 5/32" brass tube that I'll use for the rudder tube. Easy.

I spent some time 3D modeling the fin, bulb and rudder. Here's how it looks so far:

Obviously the fin will need to be cut down. This is where I am out of my experience... the whole fin box thing has me thinking a lot. Not sure how I'll approach it. But... I have as much time as I want, so I'll figure it out eventually!

I'm completely booked for the next couple weeks and won't be able to work on it, but will start up again on the Corbie 5 IOM when I return in January!

Aloha and happy holidays!


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