Steering wander

A forum for discussing topics relating to MacGregor Powersailor Sailboats
Post Reply
User avatar
gyroplanes
Engineer
Posts: 197
Joined: Thu Nov 06, 2008 12:23 pm
Sailboat: MacGregor 26X
Location: Lansing, Illinois (Chicago, so suburb)

Steering wander

Post by gyroplanes »

My :macx: (1998) Suzuki DF90 was no fun to pilot up the mighty Calumet River (south Chicago) I had all I could do to keep it between the banks.

I noticed the PO had changed the steering cable to the new, preferred, option. Being nice to Ohana after seasons of neglect, I decided to opt for hydraulic steering. I bought the unit and found it easy to install (not so much, the hoses) filling and flushing was easy.

WOW, what a difference. Precise and instant handling.

I would offer the details of the brands, but Ohana is on the hard at the marina and I am 17 miles away. If any paperwork survived the great mold takeover I can provide the info when the mold lets me back in.
User avatar
NiceAft
Admiral
Posts: 6701
Joined: Tue Feb 01, 2005 7:28 pm
Sailboat: MacGregor 26M
Location: Upper Dublin,PA, USA: 2005M 50hp.Honda4strk.,1979 Phantom Sport Sailboat, 9'Achilles 6HP Merc 4strk

Re: Steering wander

Post by NiceAft »

“Precise and instant handling. ”

I read this, and was surprised. Several years ago I was allowed to take the helm of a 60 foot catamaran. The captain warned me that because of the boats hydraulic steering, “there will be a delay in reaction to wheel movements”, and he was correct. So, when I read “instant handling”, I am a bit surprised.

Ray

Image
User avatar
gyroplanes
Engineer
Posts: 197
Joined: Thu Nov 06, 2008 12:23 pm
Sailboat: MacGregor 26X
Location: Lansing, Illinois (Chicago, so suburb)

Re: Steering wander

Post by gyroplanes »

They probably had an air bubble in the system?

As I understand, since a liquid is almost nearly in-compressible, any action is transmitted and actuated at the speed of sound through the fluid.
Think of auto brakes.

My :macx: hydraulic conversion made all the difference in the world.
User avatar
NiceAft
Admiral
Posts: 6701
Joined: Tue Feb 01, 2005 7:28 pm
Sailboat: MacGregor 26M
Location: Upper Dublin,PA, USA: 2005M 50hp.Honda4strk.,1979 Phantom Sport Sailboat, 9'Achilles 6HP Merc 4strk

Re: Steering wander

Post by NiceAft »

gyroplanes wrote:They probably had an air bubble in the system?

As I understand, since a liquid is almost nearly in-compressible, any action is transmitted and actuated at the speed of sound through the fluid.
Think of auto brakes.

My :macx: hydraulic conversion made all the difference in the world.
Makes sense, except for the speed of sound statement. I should have remembered that a liquid can’t be compressed. Pressure on one end, pressure on the other.

Ray
DaveC426913
Admiral
Posts: 1912
Joined: Mon Jul 14, 2008 8:05 am
Sailboat: MacGregor 26X
Location: Toronto Canada
Contact:

Re: Steering wander

Post by DaveC426913 »

NiceAft wrote: Makes sense, except for the speed of sound statement. I should have remembered that a liquid can’t be compressed. Pressure on one end, pressure on the other.
No, he's correct about that. Pressure waves travel at the speed of sound of the material.

Now, since that's somewhere in excess of 4km/s for hydraulic fluid, it is effectively instant (~ 1 millisecond) over the length of a steering cable.
User avatar
NiceAft
Admiral
Posts: 6701
Joined: Tue Feb 01, 2005 7:28 pm
Sailboat: MacGregor 26M
Location: Upper Dublin,PA, USA: 2005M 50hp.Honda4strk.,1979 Phantom Sport Sailboat, 9'Achilles 6HP Merc 4strk

Re: Steering wander

Post by NiceAft »

DaveC426913 wrote:
NiceAft wrote: Makes sense, except for the speed of sound statement. I should have remembered that a liquid can’t be compressed. Pressure on one end, pressure on the other.
No, he's correct about that. Pressure waves travel at the speed of sound of the material.

Now, since that's somewhere in excess of 4km/s for hydraulic fluid, it is effectively instant (~ 1 millisecond) over the length of a steering cable.
I am always amazed at the varried knowledge on this site. I knew about the liquid not being able to being compressed, just not about the speed of sound factor.

Gyroplanes, my humble apologies.

Ray
bwygirl
Engineer
Posts: 189
Joined: Thu Feb 19, 2009 3:45 pm
Sailboat: MacGregor 26M

Re: Steering wander

Post by bwygirl »

How did you find the boat handle with hydraulic steering when sailing? Were you able to feel the steering at all? Ok, yes folks before you jump on me, it is difficult to feel the steering of the MacGregor under sail but it is possible. It just takes some practice. If possible handle a tiller steered boat sometime and then go to your X or M, you will be able to feel the steering as the rudders catch the water and begin the turns. I have not sailed a boat with hydraulic steering. Now, motoring yes that would be good.
User avatar
NiceAft
Admiral
Posts: 6701
Joined: Tue Feb 01, 2005 7:28 pm
Sailboat: MacGregor 26M
Location: Upper Dublin,PA, USA: 2005M 50hp.Honda4strk.,1979 Phantom Sport Sailboat, 9'Achilles 6HP Merc 4strk

Re: Steering wander

Post by NiceAft »

bwygirl wrote:How did you find the boat handle with hydraulic steering when sailing? Were you able to feel the steering at all? Ok, yes folks before you jump on me, it is difficult to feel the steering of the MacGregor under sail but it is possible. It just takes some practice. If possible handle a tiller steered boat sometime and then go to your X or M, you will be able to feel the steering as the rudders catch the water and begin the turns. I have not sailed a boat with hydraulic steering. Now, motoring yes that would be good.

At first, I did not understand what you meant by "feel the steering", but then realized what you meant.

On my :macm: (no hydraulic steering) , it took me awhile to get the "feel" as you said.

On that 60' catamaran, it was not easy to keep on a course, but now I realize a bubble was probably in the hydraulics.

I'd also like to see gyroplane's answer to your question.

Ray
User avatar
Highlander
Admiral
Posts: 5995
Joined: Wed Sep 21, 2005 8:25 pm
Sailboat: MacGregor 26M
Location: Maccutter26M 2008 75HP Merc. 4/S Victoria BC. Can. ' An Hileanto'ir III '
Contact:

Re: Steering wander

Post by Highlander »

I know Ross installed hydraulic steering on his M & said he lost the helm feed back with it that he had with the cable system when the eng. was disconnected !
J 8)
DaveC426913
Admiral
Posts: 1912
Joined: Mon Jul 14, 2008 8:05 am
Sailboat: MacGregor 26X
Location: Toronto Canada
Contact:

Re: Steering wander

Post by DaveC426913 »

NiceAft wrote:
DaveC426913 wrote: I am always amazed at the varried knowledge on this site. I knew about the liquid not being able to being compressed, just not about the speed of sound factor.
Admittedly, my knowledge comes, not from mechanics, but from physics.

Online discussions about infinitely rigid poles transmitting signals at super-relativistic speeds invariably lead to explanations of mechanical transmission in real-world materials. :)
User avatar
NiceAft
Admiral
Posts: 6701
Joined: Tue Feb 01, 2005 7:28 pm
Sailboat: MacGregor 26M
Location: Upper Dublin,PA, USA: 2005M 50hp.Honda4strk.,1979 Phantom Sport Sailboat, 9'Achilles 6HP Merc 4strk

Re: Steering wander

Post by NiceAft »

Yeh,
Whatever you just said :D

Ray
Post Reply