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Old 14 April 2004, 10:20   #1
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Propeller guards

I will be doing some close-quarter work in sea caves and along rock formations. Jet drives are impractical where I am because of a lack of servicability. Do prop guards have an affect on speed or maneuverability, i.e. increased drag? Is one style better than another for outboards or sterndrives?
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Old 14 April 2004, 13:50   #2
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Hi Robbie
Try a search of the forum for propguards as the subject was look at some time ago with varing opinion
Alistair
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Old 14 April 2004, 15:06   #3
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Will do... thanks aligator
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Old 14 April 2004, 17:23   #4
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We design prop guards at work and unfortunatly they do reduce your speed alot, probably upto a third less speed!!.
They are mainly used by diving groups how have people in the water with the boats.
They are an alternative to jet drives and maybe better in some ways as they are very easy to put on and take off. Lots of people put them on when they need to and take them off when they dont.
It depends on how much loss of speed you can put up with.
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Old 14 April 2004, 17:50   #5
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The RYA did a prop guard test at the end of last year. They found that they reduced performance and handing. Some actually sucked objects into the guard which would subsequently get stuck between the prop and the guard. This was apparently demonstrated using a leg of pork to give the effect of what would happen to a human limb!
The guards are exactly what hey say "prop Guards" rather than person protection.
The Zap Kat prop protection is apparently one of the best designed items which they tried.
Their findings state that better driver training is better than fitting guards to protect a person in the water.
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Old 15 April 2004, 20:51   #6
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Thanks for the responses. I'm surprised at not finding one that's more geared towards simple protection of the prop with minimal loss of power. I'll only be working in deep water, so my main concern is turning around or backing up in a sea cave and catching a blade along the jagged rock wall. Very small chance with a good driver, but it can't hurt to be too careful.
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Old 16 April 2004, 04:13   #7
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Quote:
Originally Posted by Robbie D
I'm surprised at not finding one that's more geared towards simple protection of the prop with minimal loss of power. .
If only, experiences with inflatables and dive boats that have been fitted with them was not good and not helped when baots are fully of divers and heavy exquipment the loss of power really makes the difference between getting up onthe plane or just running at displacement speeds so I won't entertain them on my boats even when diving.

Pete
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