Reply
 
Thread Tools Display Modes
 
Old 04-17-2015, 11:27 AM   #1
Member
 
City: Whitehall Mi.
Country: USA
Join Date: Jan 2015
Posts: 13
Rudder modification

I recently read an article about a modification for trawler rudders. An academic group reshaped the flat plate rudder of a working trawler with a specific NACA profile. The end result was improved rudder response and increased rudder angle before stalling. Does anybody have any experience with this?

Dan Girvan
Gypsy Spirit
Albin 36
__________________
Advertisement

Gypsy Spirit is offline   Reply With Quote
Old 04-17-2015, 11:50 AM   #2
Guru
 
jleonard's Avatar
 
Join Date: Jun 2008
Posts: 2,735
If you do a search you'll find a thread or two about this.
__________________

__________________
Jay Leonard
Attitude Adjustment
40 Albin
Mystic,Ct
jleonard is offline   Reply With Quote
Old 04-17-2015, 01:47 PM   #3
Guru
 
Nomad Willy's Avatar
 
City: Concrete Washington State
Country: USA
Vessel Name: Willy
Vessel Model: Willard Nomad 30'
Join Date: Oct 2007
Posts: 13,701
If you have big rudders and go 7 knots you might try rigging your rudder to get more deflection. There were three holes on my rudder horn and I moved the hyd cyl rod attach point to the hole closest to the rudder shaft. Turns real sharp now. Had it that way for many years. You will need to exert more force at the helm to overcome the lesser mechanical advantage. My rudder deflects 45 degrees each way. To take advantage of the increased deflection there's a good chance you'll need to make your rudder bigger. Keep the percentage of rudder area ahead and aft of the rudder shaft the same as the original and if you stray in this regard error in the direction of too much rudder area aft. When you modify things you always take the chance you'll discover things you never thought of .. sometimes in a very painful way. I've had good luck w mods but .......

Definitely do jlenord's suggestion and look in the archives. There have been extensive discussions .. good ones.
__________________
Eric

North Western Washington State USA
Nomad Willy is offline   Reply With Quote
Old 04-17-2015, 02:00 PM   #4
Guru
 
LarryM's Avatar
 
City: League City, TX
Country: USA
Vessel Name: Pelago
Vessel Model: Wellcraft 3300 Coastal
Join Date: Aug 2011
Posts: 842
Do a Google search for:

Schilling Rudder
Fishtail Rudder
MacLear Thistle Rudder

This will get you started in the right direction. There's a lot of available information on these rudders. Be sure to check out YouTube too.
__________________
Larry
M/V Pelago
LarryM is online now   Reply With Quote
Old 04-17-2015, 02:27 PM   #5
TF Site Team
 
Larry M's Avatar
 
City: JAX, FL
Country: USA
Vessel Name: Hobo
Vessel Model: Krogen 42-120
Join Date: Nov 2008
Posts: 5,721
Here's a link for a rudder modification that Mike Thompson did on his Defever 40 Passagemaker plus a bunch of other modifications. (His wife, Melissa, has kept his web site up since his passing)

Rudder
Larry M is online now   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





All times are GMT -5. The time now is 02:22 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012