Rudder from scraps (part 2)
By Eric Comstock
Hi Shorty,
As promised, I'm reporting back on how my rudder build from scraps has worked out.
Overall, considering it was something I threw together in just a few minutes, it has worked well. I'm reasonable happy with the mechanics of it, but it is too small. The blade is made from a 1x6 plank (0.75" x 5.5" true dimensions) about 2.5' feet long. I knew from the start tat it only had about 1/2 the surface area that is commonly recommended. This causes a number of difficulties:
When sailing down wind, if the boom is out more than 45 degrees, the rudder can not stop the boat from heading up into the wind. When coming about, you can not point up right away, you have to fall off a little to build up speed first. Low speed maneuvering is sluggish and imprecise. Now, after sailing with it for a few weeks and learning it's shortcomings, I have very little difficulty "maneuvering" around them, so to speak and it is a perfectly serviceable rudder. While I will eventually replace it with one that is larger, I'm not in any hurry. It has been a useful test bed and I still have a few more experiments to carry out on it before I retire it.
I did find that, while using a 3/8" hole in the tiller that would seat on to the bolt that the rudder pivots on added a lot to the rigidity to the mechanism, it would tend to pop out of that hole if I was not careful. I added a bungee cord to hold the tiller down onto the pivot bolt and that helped a lot.
One time when the tiller did slip off the bolt and I didn't notice right away, the remaining bolt holding the rudder to the cheek bent. I need to add some sort of reinforcement that will support the rudder at the bottom of the cheek when it is down.
I have also noticed another issue with my boat that this rudder may help with. My lee board warps when it gets wet.
As you can see in this picture that I took right after pulling out yesterday, the lee board is bent over and touching the hull. After it is out of the water for a day or two it will straighten out. This tells me that the Thompson's water seal I put on it is not sealing as well as I had hoped. Since that is all that is on most of my boat I can see that something more will be needed. There are issues with placing some coatings over Thompson's, so I will need to be careful what I do.
One thing that I have been wondering for a while is how well Min-wax Polyurethane Varnish would work on a boat. I have a couple of old cans of it laying around, so I coated the rudder blade with it. First I want to see how well it works over Thompson's, second how it looks on the boat and third how well it seals out water.
So far it seems to be fine over Thompson's. The color I had laying around is redder and darker than I would want to use for the boat and I can't say yet how well it keeps out water. I'm going to paint some on my lee board (once it dries out and straightens up again) and see if it keeps it from warping when wet. If it does keep the lee board from warping, I'll get a color I like more and paint the entire boat with it.
I'll let you know how it turns out.
Eric
Director of Useless Experimentation
Houston Space Duck Viking Marauder Horde Fleet