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20-06-2006, 09:17 AM
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#1
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Large member
Country: England
Location: On the farm
Occupation: General Trouble Causer Salterns Boatyard
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Boat name: Seahorse.org
Boat make: a V24 and a SLOW unstable ICE Bladerunner
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Prop crack
Any recommendations on repairing a crack on my prop? The smaller of the two out of the duoprop set has a large crack, and this is causing quite a problem..
Personal experiance recommendations please, not just a list of everyone who can fix things..
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20-06-2006, 12:24 PM
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#2
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Registered User
Location: poole dorset
Join Date: Mar 2004
Location: poole dorset
Posts: 868
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Get a new set. Dont bother repairing it will go somewhere else.
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20-06-2006, 01:02 PM
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#3
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Registered User
Join Date: Mar 2004
Posts: 6,891
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If it's near the root, I tend to agree with Chris.
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20-06-2006, 04:42 PM
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#4
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Aged Member
Country: UK
Location: HAMPSHIRE
Occupation: Safety Engineering
Boat name: Savannah
Boat make: Princess 415
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Absolutely...
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Land was invented to give boats somewhere to visit
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20-06-2006, 07:23 PM
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#5
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Large member
Country: England
Location: On the farm
Occupation: General Trouble Causer Salterns Boatyard
Interests: Official smartass
Boat name: Seahorse.org
Boat make: a V24 and a SLOW unstable ICE Bladerunner
Engines: 2x300 promax, 320 Volvo
Cruising area: England/France & Med
Join Date: May 2005
Location: On the farm
Posts: 2,681
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No body has been able to replicate the prop.
It cavitates on two of the blades, not the third, yet is 1 mile faster than the closest matching prop
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20-06-2006, 07:34 PM
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#6
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Registered User
Join Date: Mar 2004
Posts: 6,891
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It "might" be possible to weld if heated up good and hot before hand. I suspect a normal prop repair place would be tig welding it, which induces loads of stress into the material, hence not so good for you. But "if" the prop is hot enough when welding, the overall induced stresses should be low enough. Heat treating after welding would also help.
But, in conversation with Jon the other day, we reckon the rear prop does feck all anyway, which the fact your fastest prop is the one that cavitates (ie the rear prop unloads) supports. Reckon you should cut the blades off the rear prop, just run the hub, and see what happens.
You could also reshape the leading edge of the rear prop to force it to cavitate, or just cut the blade diameter right down.
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20-06-2006, 07:36 PM
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#7
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Registered User
Join Date: Mar 2004
Posts: 6,891
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Should add, it's been 10 years since I did metallurgy, so I reserve the right to be talking shite!
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20-06-2006, 10:20 PM
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#8
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..
Join Date: Jun 2004
Posts: 1,567
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Quote:
Originally posted by Matt
But, in conversation with Jon the other day, we reckon the rear prop does feck all anyway, which the fact your fastest prop is the one that cavitates (ie the rear prop unloads) supports. Reckon you should cut the blades off the rear prop, just run the hub, and see what happens.
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so do you reckon it would be better to a "SP" lower rather than the "DP" ??
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20-06-2006, 10:45 PM
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#9
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Registered User
Join Date: Mar 2004
Posts: 6,891
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Yeh, more top speed, but probably at the compromise of handling and acceleration.
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20-06-2006, 11:27 PM
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#10
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Large member
Country: England
Location: On the farm
Occupation: General Trouble Causer Salterns Boatyard
Interests: Official smartass
Boat name: Seahorse.org
Boat make: a V24 and a SLOW unstable ICE Bladerunner
Engines: 2x300 promax, 320 Volvo
Cruising area: England/France & Med
Join Date: May 2005
Location: On the farm
Posts: 2,681
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Quote:
Originally posted by Matt
But, in conversation with Jon the other day, we reckon the rear prop does feck all anyway, which the fact your fastest prop is the one that cavitates (ie the rear prop unloads) supports. Reckon you should cut the blades off the rear prop, just run the hub, and see what happens.
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OK,
The front prop is 100%
I have a spare rear prop, which is thinned and balanced - it is also as close to the same spec as the existing race prop.
*BUT*
When I tested combinations of props, the race front prop with the spare rear prop was almost a mile slower than the full race setup. I already tested that whilst trying to get the most speed out of the boat. Why??
FWIF, I do have a very very very trimmed rear prop - it was a broken one I picked up for next to nothing, and 'worked' it down to 9 inches, thinned and cut away as well. Handling goes for a ball of shite, but it does add about 1/2 a mile onto the top speed - so I feel sure I will get the British Speed record for V24 this season.
All the work and experimentation for Conniston last year is definately paying off in the V24 Championships this year......
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12-07-2006, 12:25 AM
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#11
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Registered User
Location: Scotland
Interests: Hole maker
Boat make: Humber Ocean Offshore
Engines: KAD 300/DPX
Join Date: Mar 2004
Location: Scotland
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Quote:
Originally posted by Matt
...But, in conversation with Jon the other day, we reckon the rear prop does feck all anyway, which the fact your fastest prop is the one that cavitates (ie the rear prop unloads) supports. Reckon you should cut the blades off the rear prop, just run the hub, and see what happens.
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Matt, would you like to share your conversation?
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