Composite Props?

Discussion in 'Prop Shop' started by rkmurphy, Apr 11, 2009.

  1. rkmurphy

    rkmurphy Well-Known Member

    Are they any good? Or a waste of money?
     
  2. Brett

    Brett > PRO STAFF <

    I don't know.
    I'm still reading.
    Might take a day or two.
    The link is a compilation of links to everything marine propellers.

    http://www.virtualpet.com/otcc/rigging/props/props.htm#compare

    Good question RK, this ought to keep me busy a few days.
     

  3. TomFL

    TomFL Well-Known Member

    I've read they can be used as primary props, some even have replaceable blades. Some guys keep them as a lightweight, inexpensive spare.

    From what I've seen most people that use them as primary props are from up north, in deep lakes.

    I doubt they'd hold up in our environment where hitting bottom is a regular occurence, but that's just my guess.
     
  4. Jacbo

    Jacbo Well-Known Member

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    My friend had one on his 30 hp Suzuki on a 11' whaler. It was a 4 blade composite with replaceable blades and I believe adjustable pitch. We would hit bottom regularly but not excessively and it held up fine, but on one trip to the port about 5:30 am we hit something SOLID at 25+ mph in the channel. Aside from being freaked out we were fine, but apparently the prop wasn't. The engine was acting like there was no load on it whatsoever and the boat was crawling forward. I thought we had either spun the prop fully or lost it all together, but upon tilting up the engine we noticed that we had completely lost 3 out of 4 propeller blades and were now being powered by one approximately half dollar sized blade. :eek:

    It seems that, at least on this model of prop, instead of using a conventional rubber hub, the manufacturer made it so the blades would pop out if a great enough force is put on the prop. While this may have sounded like a good idea at the time, I find it much easier to limp back to the dock on a half-spun or spun alu/S.s. prop than a half-gone or gone composite prop. ;D
     
  5. TheBrazilNut

    TheBrazilNut Guest

    They are used more and more as rental boat props. I rented a CC on the Keys last yr and getting out of out little harbor at lotide was very tricky even with the engine up. Ended up hitting a rock coming back in and damaging one of the blades. Just take the prop off change the blade that was damaged and good as new. It cost us about $25.
     
  6. rkmurphy

    rkmurphy Well-Known Member

    Thanks for the replies.  Keep em coming!

    http://www.piranha.com/enginelist.php?id=2184&submit.x=23&submit.y=6&submit=submit

    $115 for a complete prop.  Not bad.  $177 for complete prop, floating prop wrench, 3 replacement blades, and bag for parts.  Even better.

    According to this, though, with my OEM prop pitch (which is 10 3/8 x 13) I should be producing between 23 and 30 mph.  I'm getting 31, maybe even 32.  Could this mean I'm turning too many RPM?  Or is it fine that I'm pushing what I'm pushing?
     
  7. Brett

    Brett > PRO STAFF <

    Flat bottom hulls are easier to plane than a modified vee.
    More speed from less uuumph. Air pulled under the flat
    hull cuts friction so you go faster easier. The only way
    to know your rpm is with a tach, guessing not allowed!

    ;)
     
  8. rkmurphy

    rkmurphy Well-Known Member

    Thank you Sensei :)
     
  9. TomFL

    TomFL Well-Known Member

    A mercury AL propeller will probably run you a good bit less than the composite $$'s you posted.

    Shoot Cap'tRon a PM, he's the guy you need to be talking to.

    -T
     
  10. rkmurphy

    rkmurphy Well-Known Member

    Already did. Looking at getting mine (aka Alex's old one :) ) reworked by a place locally that Capt Ron recommended. He's a very helpful guy.

    The OEM aluminum prop from Mercury is $120. I wonder if I could get it cheaper somewhere...but I doubt it'll be close to the price of a rework.

    Composite looks tempting...adjustable pitch...lighter...cheap fixes (~$17 ea blade). But I don't know if they pose any disadvantages...
     
  11. B.Lee

    B.Lee Well-Known Member

    There should be lots of used aluminum Merc take off's out there. Ebay?
     
  12. The_Skiff_Shop

    The_Skiff_Shop Well-Known Member

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    That's crazy. :eek: An OEM PT Prop is $89.00 and that includes shipping.
     
  13. rkmurphy

    rkmurphy Well-Known Member

    What?!?!?! Brand new w/ hub?!?!?! If so we need to talk. PM me or email me @ dkickmurphys526@msn.com.