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Line cutters

Discussion in 'Technical Discussion' started by Tashmoo1, Feb 11, 2012.

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  1. Tashmoo1

    Tashmoo1 New Member

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    Feb 4, 2012
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    Location:
    Cape Cod - Falmouth
    I am thinking of adding line cutters on our boat and considering Spurs and Shaft Razors. My concern is will either of these create a problems with water flow over the wheels? We cruise between 22 knots and 32 knots and don't want to develop either cavitation or ventilation. I need to check the spacing between the prop and strut to see if the Shaft Razors will fit. If there is another solution that I missed, please let me know. Also do Spurs require a lot of maintenance and do they work well?
  2. Pascal

    Pascal Senior Member

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    Miami, FL
    Well you never really know if they work, until they don't!

    we have spurs on the 70 footer I run and they always seem to be shedding parts... Which are expensive!

    We had them installed since we run in new England, often in fog and or at night, otherwise save your money

    No issues at speed (22kts cruise)
  3. RT46

    RT46 Senior Member

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    Feb 22, 2011
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    Long Island, NY
    I have them also,
    you dont notice them when you have them.

    but you know you dont have them when you pick up a lobster pot or some line get fowled in the wheels.
  4. PropBet

    PropBet Senior Member

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    Is Everything!
    We have them. It's the few bucks you spend to never know if you actually needed them or if they work.

    Conversely, if you don't, and foul a prop, you sit there in the blue thinking "I really should have spend the few bucks".

    On goes the dive gear. May as well scrub the hull while you're down there.

    Irony.
  5. RT46

    RT46 Senior Member

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    Location:
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    yea, i had to get in 50 degree water in Maine one time without a wet suit to cear the the prop of a lobster pot that i picked up in a crowded harbour entrance.
    Sometimes, no matter how hard you try to avoid them you still pick em up.

    btw the cold swim wasnt fun....

    another time i had some polypro floating line all balled up on one of the wheels, the engine was vibrating and wasnt making top power, i went through hell thinking something was really bad with the engine or transmission, only to find out that there was a giant ball of that floating yellow rope around the wheel.

    the cutters are now on the boat....
  6. C4ENG

    C4ENG Senior Member

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    Location:
    Ft Lauderdale
    I have heard of a lot of situations where a vessel had a vibration problem and they suspected the line cutters being part of the problem. They would remove the gear only to find the cutters where not the problem.
  7. Capt J

    Capt J Senior Member

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    I've found that the line cutters only work maybe 50% of the time if that. A lot of times the lines gets wrapped onto the shaft in front of them and they aren't effective.
  8. luckylg

    luckylg New Member

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    Mar 18, 2008
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    Location:
    Portland, OR, USA
    Every trip I make up the coast of Washington (or down the coast of Oregon) is a game of dodge the pots. In ten years I've only picked up one. A combination of the cutter and backing down (as a precaution) completely cleared the mess and we continued our trip without a dive. My customer reports that he's picked up other lines on occasion and never had a situation where the line cutters didn't do their job.

    Two enthusiastic thumbs up from me.
  9. Laurence

    Laurence Senior Member

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    Aug 30, 2006
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    Location:
    Chattanooga TN
    Wish I had cutters

    Muscadine grape grows wild here in the South. Two weeks ago with the river running at flood, while moving my Roamer 125 miles upriver, I hooked a tangle on the starboard prop that rolled it into a ball. 45 minutes later with boat hook and reversing, it was mostly clear. I wish I had cutters! Tennessee River, who woulda thought?
  10. H4M

    H4M Guest

    QuicKutter line cutters

    Have a look at quicKutters™ these have replaced Spurs cutters on the UK RNLI offshore lifeboats (like the US coast guard boats) and the Royal Navy, they are also used by Christensen Yachts (replacing Spurs)

    The reasons have been that they are more robust and seem to have less effect on water flow. No independent trials have taken place but the overall profile is far less obtrusive to water flow.
  11. Pascal

    Pascal Senior Member

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    I saw the Sharks Cutters the Miami boat show; one piece, simple design. We re going to put them on to replace the Spurs.
  12. H4M

    H4M Guest

    The trouble with the simple discs as I see it is that any debris caught by a prop blade will hence be rotating with the shaft/prop/cutter disc, this means that the disc will not be slicing as the debris eventually wraps over it. True that a very sharp blade (like a razor) may slice with just pressure but I doubt any of the disc cutters would cut through rope just pulled hard across them.

    You could check this theory by simply pushing a rope across the fixed blade, some tests have show what happens if the rope is held by the strut but I think it is more likely debris will be caught by th erotating blade.