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View Full Version : Kick-up rudder cheeks...bolt through? or screw?



bobkaschak
05-21-2003, 01:19 PM
I am going to convert the rudder on my 12 ft daysailer to a kick-up. I am using 1/8" bronze plate appx 7" x 10" for the cheeks. Should I "bolt through", or "screw" the cheeks to the lower (moveable) part of the rudder? The pivot is going to be 1/2" brass rod in a bronze bushing epoxied into the wood.
Thanks in advance,
Bob K.

http://www.imagestation.com/picture/sraid61/pc2f9fd9c462737f9b0e8ba8b03f0a994/fc269d40.jpg

Venchka
05-21-2003, 05:58 PM
[QUOTE]Originally posted by bobkaschak:
[QB]...Should I "bolt through", or "screw" the cheeks to the lower (moveable) part of the rudder? The pivot is going to be 1/2" brass rod... Bob K.

Something ain't right, as my Cajun buddies like to say. What's fixed and what pivots? Will there be a rudder head with space between the cheeks for the pivoting blade to fit? If so, through bolts & epoxy glue seem appropriate for the rudder head make up.

Why brass through bronze bushings? A 3/8" bronze bolt or rod peened over on one end would make an adequate pivot bolt. The bronze bushings or ok but seem like overkill. Somewhere on the Forum I recall a method of filling oversize holes with thickened epoxy and then drilling the correct size hole through the epoxy. I suppose you could do both, filling the epoxy hole with a bronze bushing.

JimConlin
05-21-2003, 06:14 PM
I'd use FH bronze machine screws, tapped into the 1/8" plate. A smart whack with a center punch will keep 'em from backing out.
Certainly a bronze bushing is ideal, but if that's not available, there are a couple of ways to form a glass-epoxy bushing. If you have the stock, G-10 glass-epoxy tube is fine for this. It's ~$40 for a 3' length, so that might not make sense. I have some 5/8" ID and i could cut a piece for you if you like.

The other way, thanks to the Gougeons, is to wrap some wet glass cloth around a bolt, inser bolt-wad through sloppy hole in your part, and tighten nut against fender washers. It compresses what's in the bore. Spray the bolt w/ Pam or wax it so it can be removed. Clean up with belt sander.

JIm

bobkaschak
05-21-2003, 09:23 PM
Thanks Jim, I never thought about tapping into the bronze plate, I really like that idea. I guess this way, I could countersink the one side, tap the other side, and keep both sides flush. I got a bronze bushing (1/2" ID, 11/16" OD) from the hardware store for $2.30. Thanks for the offer. The reason I am using 1/2" (overkill?), is, I have a piece of 1/2" brass laying around. I will post some photos of the progress in the morning.
Best regards,
Bob K.

bobkaschak
05-22-2003, 08:16 AM
Here is what I have so far....

http://www.imagestation.com/picture/sraid63/pb03c0badc3437516df7f929abf27aaa7/fc198264.jpg

Venchka
05-22-2003, 08:58 AM
Oh, yes, well, now I get it.

You will have bronze to bronze for the pivot, right?

Nicholas Carey
05-23-2003, 01:54 AM
Question is...What stops it from kicking up on its own, just from the waterflow?

On the International 470s (http://www.470.org/) I used to sail, the kickup rudder had a shockcord lanyard set up—For the rudder to kick up, it had to streeeeeeetch :D the shock cord. To do that needed a little help from something like a solid object giving the rudder a whack.

The lanyard also acted as keeper to keep the rudder attached. The tension on the lanyard kept the rudder on the gudgeons.

bobkaschak
05-28-2003, 08:08 AM
I cast a 4" disk (about 4 lbs) of lead, and epoxied it into the rudder, and that should keep it down. Here is the final product. The block assembly (including the sheave) is homemade.

http://www.imagestation.com/picture/sraid63/p2f4037cbcb6026e0725b8b9d900216ab/fc0e77e7.jpg

http://www.imagestation.com/picture/sraid63/pb52f4bece6434ad6a5d2e856581b2370/fc0e77f7.jpg