barn-door rudder

[CaptainDaniel]

I need to build a big transom rudder the size of a barn door. It's only a temporary solution to move the boat. So realistically speaking it has tho work for a week in good weather. I was thinking of keeping it as an emergency rudder. I need to move my boat to a better harbor now. So I have the luxury on picking a good day with good weather. The boat will be motored not sailed for now. At the current location I can't get the boat out of the water to fix the real rudder. That's why I need a temporary one to begin with.

Can someone help with some general trips on a ruder that size. I probably can make it a bit smaller, but need some suggestions on the how. Can I use marine plywood or does it have to be boards? I also wonder how to effectively attach the rudder to the back of the boat. I have a metal guard rail on the back which is very stable and solid. How large should I make the tiller?

[robherc]

Can you give us some info (LWL, BWL, displacement, hull-type) on your boat, and maybe post a couple pictures (preferably out-of-water, if you have them). So we can see what you're working with?

[CaptainDaniel]

here are some pictures.







Measurement, not sure what you need. The boat is about 50 feet long, 8 foot draft, full keel design sailboat (ferro-cement). It does not currently have a mast/sail. I plan on using it as a motor boat until I get a mast/sail. Below is the only out-of-water pic I have. You can see the rudder next to a drum and a hull-only pic. Not the best quality. The original rudder is about 16.25 square feet total area. I will worry about a new one after I move the boat and get it out of the water.



I also found this emergency rudder and was wondering if anyone would recommend this as a temporary solution. Again, this is only to move the boat, not to cruise or anything else.

If you need any other measurements, let me know.

[PAR]

Bolt a set of pintals and gudgeons to the transom and hang a piece of plywood off the stern. Use a tiller to steer. The rudder you've pictured looks to be one of the most inefficient arrangements I've seen. Make the rudder slightly bigger then what you have and use a long, strong tiller arm.

[CaptainDaniel]

Could I use something like this, but use plywood instead of sail?

What thickness of plywood would you suggest?

http://www.sailorsonamission.org/content/view/41/70/

How far are you going? Consider locking present rudder in place slighty to port of amidships for a lefthand screw and dragging an appendage, i.e., a bucket, on the side to which you want to steer. A dingy could provide assistance. I wouldn´t bolt anything to that old ferro-cement transome. Why can´t you use present rudder? Consider your options - the best would be to get ahold of that rudder post from above somehow and hand steer - an emergency steering arm? jeez, with this low speed operation you could even tie lines to the rudder and tie them off to the railing (or cleats - I can´t quite tell). Slow way down, slack one a bit and tighten the other. Protected water, all the time in the world - relax!

[CaptainDaniel]

I need to go about 70 miles, but will plan several short trips, not all in one go. The original rudder is gone as in it fell off and is lost.

I hate to give this advice, because if weather DOES come up... But I´d just run with it - try steering with buckets, a towing (steering) skiff. I know you are trying to save the cost of a haul-out. Good luck

[PAR]

I like the idea of a tow much better as well. You'll be able to maneuver the boat better and shouldn't have fear of temporary steer arrangements failing. A small skiff could push the boat to a reasonable speed. With frequent stops along the way, it should be manageable.

I wouldn't attempt steering with buckets or any other type of drag device. It's way to easy to loose control or not have enough way on to effectively turn or stop the boat. This is a last resort tactic when at sea and trying to get home with a dead steering system.

If you elect to arrange a rudder, then I wouldn't get much more elaborate then a steering oar or gudgeon hung affair. A steering oar would be easiest. This would be just a sweep, loosely attached to the stern rail (you could tie it on with line). It hangs over the stern, like a sculling oar. You could hook tackle to it to make the effort easier.

[TeddyDiver]

Originally Posted by PAR

A steering oar would be easiest.

Gets my vote!

[CaptainDaniel]

I like the idea of a steering oar. Any suggestions on what size cause I would have to build it first.

[TeddyDiver]

Depends a bit how long you make them. Them bcs I'd recommend to make a pair of them. If the are angled back about 45 deg believe some 5sqf/oar is enough.. thats however just a quess..