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23-01-2008, 06:00
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#1
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Registered User
Join Date: Sep 2007
Location: Shanghai, China
Boat: Dix 43 CC, steel, 43 ft
Posts: 149
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Shaft Brakes
I did a search on the forum, but could not really find the information I need. Neither on the web with an extensive Google search.
My question is the following:
In my Dix 43 I will install a Yanmar 4JH4AE (54 hp @ 3000 rpm) with a ZF30M mechanical gearbox (2.15:1). In order to prevent the shaft from rotating while sailing, I would like to install a mechanical shaft brake. I like this solution better than having the transmission in reverse, like many do.
Now I am looking for a suitable shaft brake. Does anyone have experience with this? Can anyone give me a brand name?
Thanks in advance,
Andreas
__________________
'How inappropriate to call this planet Earth when it is quite clearly Ocean.' - Sir Arthur C. Clarke
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23-01-2008, 06:46
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#2
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Registered User
Join Date: Mar 2006
Location: Tampa Bay area, USA
Boat: Beneteau First 42
Posts: 3,961
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Shaft Lock (or "Lok")
__________________
"It is not so much for its beauty that the Sea makes a claim upon men's hearts, as for that subtle something, that quality of air, that emanation from the waves, that so wonderfully renews a weary spirit."
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23-01-2008, 07:12
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#3
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Registered User
Join Date: Jan 2005
Location: Fiji
Boat: Westsail - CC - 42
Posts: 339
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I purchased a shaft lock but haven't installed it yet. As soon as I haul either this or next month, I'll install it and provide some feedback. The company owners are great to deal with.
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23-01-2008, 07:27
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#4
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Registered User
Join Date: Sep 2007
Location: Shanghai, China
Boat: Dix 43 CC, steel, 43 ft
Posts: 149
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Quote:
Originally Posted by svHyLyte
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Great! Thanks a lot, this is exactly what I am looking for.
Wow, that was a fast reply.
__________________
'How inappropriate to call this planet Earth when it is quite clearly Ocean.' - Sir Arthur C. Clarke
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24-01-2008, 08:59
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#5
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Registered User
Join Date: Apr 2007
Location: Seabrook, TX
Boat: Westerly Corsair 36, The Mons
Posts: 97
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We went through the same process. Do yourself a favor.
Try to nstall a feathering prop instead of a shaft brake. Shaft brakes slow you down sailing. A feathering prop will let you sail faster. It costs a bit more, but you also end up with a spare prop.
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24-01-2008, 09:24
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#6
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cruiser
Join Date: Nov 2004
Posts: 4,525
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Themons is right.
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28-01-2008, 02:03
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#7
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Registered User
Join Date: Sep 2007
Location: Queensland, Australia
Boat: None at present--between vessels. Ex Piver Loadstar 12.5 metres
Posts: 1,475
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Shaft brake
My prop starts to spin about three knots. A pal has an alternator rigged to his--when the prop spins it charges his batteries. I do not think it is a very powerful alternator though--probably boots out about ten amps or so since it is not turning vary fast--and gearing it up woul;d probably stop the prop.
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28-01-2008, 03:51
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#8
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Registered User
Join Date: Jan 2005
Location: Fiji
Boat: Westsail - CC - 42
Posts: 339
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Say many feathing props will still turn a velvet drive tranny. So you still need a brake. I found that out after I purchased and added an Autoprop. I've also read where the max prop will spin but don't have first hand knowledge of those.
Fair Winds
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01-06-2009, 06:59
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#9
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Registered User
Join Date: Jun 2009
Posts: 3
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Shaft brake situation
I have had a Gulfstar 50 sloop "Dissertation" since 1982.
It had a Byrd Brake until several years ago - I replaced the engine and installed a J folding 3 blade prop - adjustable pitch (when out of the water.)
Today I am having my Warner velvet drive only 3 years old rebuilt for the third time. The reverse gears are getting striped out because the prop continues to turn after going into neutral and then to reverse.
I am going to purchase a used Byrd brake again and install it.
Evidently when it is in neutral the brake does lock and this is the only way I can solve the problem.
The 4 blade prop I used to use is very much missed - made a great motoring experience, but I could not get the boat to move in light air.
With the J prop sailing in light air is vastly improved but I did not know to keep the shaft brake.
Those of you that discussing this - consider this delima
and feel free to contact me.
Bob Wittmann
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01-06-2009, 08:14
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#10
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Registered User
Join Date: Dec 2006
Location: Seattle
Boat: Cal 40 (sold). Still have a Hobie 20
Posts: 2,944
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Quote:
Originally Posted by dkall
Say many feathing props will still turn a velvet drive tranny. So you still need a brake. I found that out after I purchased and added an Autoprop. I've also read where the max prop will spin but don't have first hand knowledge of those.
Fair Winds
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Since the blades are completely lined up with the water flow, have no curve, and there is more blade area behind the center of rotation, Max props tend to stay feathered in most situations and therefore won't drive the shaft. See the warnings at the bottom for exceptions. I've not had my max prop open up once feathered, but I haven't been racing my boat in 30 knots of wind with the chute up to achieve 16 knots of boatspeed that I have heard sister ships have done.
John
From:
PYI Inc. Max-Prop PSS Shaft Seal Seaview Radar Mounts R&D
4) PROPELLER USE The Max Prop works automatically. By putting the engine in gear the blades will engage in either forward or reverse. The best way to feather the propeller is; - Power at 2 to 3 knots in forward.
- Kill the engine while still engaged in forward.
- When the engine has stopped, if the shaft is still spinning engage the transmission in reverse to stop the freewheeling.
You can check to see if the propeller is feathered or not by taking the engine out of gear. If the propeller is not feathered the shaft will freewheel like with a fixed blade propeller.
In that case start the engine again and repeat the three steps. If your propeller has been greased properly it will feather in a fraction of a second as soon as you stop the shaft from freewheeling. Once the prop is feathered, you can either leave the transmission in gear or out of gear, it does not matter. DO NOT kill the engine while in reverse. In this case the blades will be in the reverse position and will not feather. You can actually use this feature to drive a shaft alternator.
IMPORTANT: If the Max-Prop is installed on a vessel that can attain sailing speeds over 15 knots, it is MANDATORY to return the transmission to neutral while sailing. If the transmission remains engaged and the propeller were to open (from hitting an object or water flow) it may turn the engine, flooding it, resulting damage to the engine.
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01-06-2009, 08:45
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#11
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Registered User
Join Date: Aug 2006
Location: Skagit City, WA
Posts: 25,483
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Max props wont turn the shaft. (You may have to quickly shift to reverse and back to get it to feather, but then it is fine.)
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01-06-2009, 12:42
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#12
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Registered User
Join Date: Dec 2006
Location: Seattle
Boat: Cal 40 (sold). Still have a Hobie 20
Posts: 2,944
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Quote:
Originally Posted by Cheechako
Max props wont turn the shaft. (You may have to quickly shift to reverse and back to get it to feather, but then it is fine.)
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You're saying the manual for Max props is wrong? I've never had mine unfeather, but the manual claims it's possible in rare circumstances.
John
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01-06-2009, 12:48
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#13
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Registered User
Join Date: Aug 2006
Location: Skagit City, WA
Posts: 25,483
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Had them on five boats in the last 30 years , the catamaran had two. Never had one start turning after I got it neutral..... anything is possible I suppose.... Black Holes are a possiblility also... :>) You're kidding right? Operators manuals never misleading?
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