Its the rudders...
From the support pages:
| Hobie Forums http://www.hobie.com/au/en/forums/ |
|
| Siren's song? http://www.hobie.com/au/en/forums/viewtopic.php?f=14&t=11766 |
Page 1 of 1 |
| Author: | sunvista [ Wed Feb 11, 2009 11:49 am ] |
| Post subject: | Siren's song? |
Under certain speed and conditions my boat starts to whine or sing. I presume this to be caused by the asymmetric hulls or perhaps rudder vibration. Three questions: 1. What causes this noise? 2. Is it bad? 3. If so, should I try to fix it? When I used to crew for guys back in the seventies they seemed to think singing hulls was a good thing... like they were sailing on the edge or something. I think the sport was so new back then that they really didn't know WTF. |
|
| Author: | mmiller [ Wed Feb 11, 2009 1:19 pm ] |
| Post subject: | |
Its the rudders... From the support pages:
|
|
| Author: | Roy [ Wed Feb 11, 2009 6:41 pm ] |
| Post subject: | |
Actually I used to like to singing, it kind of added to the sensation of speed. I've never got my getaway to sing like that. |
|
| Author: | sunvista [ Thu Feb 12, 2009 6:56 am ] |
| Post subject: | |
mmiller wrote: Its the rudders... Bummer. My rudders were badly yellowed so I just finished painting them. Thanks for the explanation. I'll just tell folks that I'm sailing on the edge! 
|
|
| Author: | Rick Buchanan [ Thu Feb 12, 2009 9:41 am ] |
| Post subject: | |
Not all trailing edges are the same. The Tiger & Fox blades that I've worked on are way too thin, and can chip just like a potatoe chip. Others are way too wide which can cause severe humm & vibration. We're putting together another article for the HOTLINE which will cover these issues. |
|
| Author: | sunvista [ Thu Feb 12, 2009 10:39 am ] |
| Post subject: | |
Rick Buchanan wrote: We're putting together another article for the HOTLINE which will cover these issues. What's the HOTLINE? How do I get it?
|
|
| Author: | MBounds [ Thu Feb 12, 2009 11:01 am ] |
| Post subject: | |
On-line version is here: http://www.hobiecat.com/hobieclass/ To get a hard copy, you need to join the Hobie Class Assoc. of North America, here: https://www.hcanamembers.com/ |
|
| Author: | Barren [ Wed Feb 18, 2009 12:21 pm ] |
| Post subject: | |
I like the humming.  Usually it happens when you are going at a pretty good pace or just about to lift a hull. Didn't somebody have a story about dolphins being attracted to the hum?
|
|
| Author: | Roy [ Wed Feb 18, 2009 8:20 pm ] |
| Post subject: | |
Not that i have seen but it sure makes my dog bark lol |
|
| Author: | mdgann [ Wed Feb 25, 2009 3:35 pm ] |
| Post subject: | HUUUUUUMMMMMMM! |
Had to jump in here. I did the scissors thing and used a straight edge to check for hollows. Looked pretty good. Out on the water at about 10 knots they scream even louder. Back to the sanding board. This time I used a belt sander with 90 grit and carefully took the trailing edge down to 0.10 of and inch and squared off the back edge. Still screams. I've given up. |
|
| Author: | Rick Buchanan [ Wed Feb 25, 2009 5:05 pm ] |
| Post subject: | |
Don't give up...I've sent Matt the info for the HOTLINE article on rudder repair. Be patient. |
|
| Author: | sunvista [ Thu Feb 26, 2009 6:54 am ] |
| Post subject: | |
After Matt's suggestion I went back and took a gun sight look at the trailing edges of my rudders. I couldn't see anything that looked like a flare, bulge or even the slightest distortion on either rudder. If that is what is causing my hum it is very subtle indeed. I'm more inclined to believe it is toe-in, vibration or some other adjustment. I am going to tighten my upper castings with additional shims and will probably try the cellophane, silicone caulk trick to the lower casting. |
|
| Author: | mmiller [ Thu Feb 26, 2009 10:24 am ] |
| Post subject: | |
Some rudder materials seem to hummm more than others. I would bet you have Lexan blades. These do not have a smooth (shiny) surface. They have a glass fiber / swirl look. The harder material made it more difficult to remove the humm. It is most definitely the foil shape causing the humm... not rake or toe in. |
|
| Author: | Rick Buchanan [ Thu Feb 26, 2009 5:12 pm ] |
| Post subject: | |
Hey Sunvista, send me a private email address for you so I can send you some photos of rudder work. [email protected] |
|
| Author: | sunvista [ Fri Feb 27, 2009 6:32 am ] |
| Post subject: | |
Rick Buchanan wrote: Hey Sunvista, send me a private email address for you so I can send you some photos of rudder work. [email protected] Rick...sent as requested. Thanks
|
|
| Page 1 of 1 | All times are UTC - 8 hours [ DST ] |
| Powered by phpBB® Forum Software © phpBB Group http://www.phpbb.com/ |
|