Centerboard
Originally I was going to make the centerboard out of marine plywood and paint it, since it isn't very visible. However, the top part will be visible, and ash is a lovely wood, so.... I glued up a 1" thick ash plank out of several good boards and shaped it according to the plans and Oughtred's book. Locating the pivot point correctly worried me, so I made a pattern (before shaping the centerboard), installed it briefly in the boat, and made sure it was going to work.
Here's the completed centerbaord, ready for final sanding and finish. I want the CB to drop into the water under its own weight, so I tried my hand at lead casting for the first time. I owe a big thanks to Jim from Tom's Tire down the street from my shop. He gave me two coffee cans full of old, broken wheel weights. The downside of that is that they were very dirty and each one had a steel clip embedded in the lead. I bought a cheap steel sauce pan, set it on the Turkey frier we use to power our steam box, and fired it up. After generating a really foul smell burning off the old grease, I had molten lead with a garnish of steel clips floating on top. I scooped them out and poured the lead into a muffin tin.
These are all the steel clips left over from my lead muffin production. Once I had enough clean lead, I prepped the centerboard. I routed out the hole and ran four bronze screws into the sides. The idea (not mine) behind that is that when the lead is poured into the hole, in solidifies around the screws and cannot then fall out of the centerboard. I clamped a piece of 1/4" ply to the centerboard, heated the lead, and poured away. I set the whole assembly up over our old wheelbarrow just in case my crude system leaked. I didn't want lead all over the ground! Fortunately, the lead stayed put.
Here is a close up of the top of the pour. As you can see, I added too much - the lead is about 1/8" proud of the wood. I've read that you can plane lead since it's so much softer than the hard steel of plane irons, so I gave it a try.
Success! I'm sure the friendly guys at my local Woodcraft would be horrified that I used my Lie-Nielson low angle jack on metal (or at all - they never really understood that I bought it to use and not just to admire on my mantle!). The scrap of plywood on the left sporting the circular burn mark is what I used to form a bottom to the hole when I poured the metal. The centerboard has been sanded and is now being varnished.