Number and size of fenders for 35' catamaran?

Discussion in 'Boat Design' started by UpOnStands, Oct 27, 2016.

  1. UpOnStands
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    UpOnStands Senior Member

    can anyone suggest size and number of fenders for 35' sailing catamaran?
     
  2. Richard Woods
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    Richard Woods Woods Designs

    I like sausage fenders, not round ones, as they roll easily when leaving a dock and don't put such high point loads on the topsides. They are also easier to stow in lockers

    I did buy some inflatable fenders but they are too light and blow around just when you don't want them to.

    So 4 fenders is normally enough unless you moor in trots, so maybe 10in dia 2ft6in long

    Richard Woods
     
  3. UpOnStands
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    UpOnStands Senior Member

    thanks for the detail.
    I was hoping that the inflatables would be acceptable but windy conditions are really when you need dependable gear.
     
  4. mydauphin
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    mydauphin Senior Member

    Like anchors, variety, bigger is better, have plenty, have a plan, and lots of rope. Round ones have their uses but sausage better. Remember on a cat especially you have 6 places to put them. People like to hang on the cat.
     
  5. UpOnStands
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    UpOnStands Senior Member

    bigger is always better except at the checkout register.
    West Marine has a offer of three white 6 1/2"dia. x 23"L utility fenders -- inflatable.
    I like the dimensions and the price but Richard says otherwise (inflatable and small?).
     
  6. waikikin
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    waikikin Senior Member

    I'd say four is an ideal minimum & the sausage ones more versatile as they can lash to fenderboards for laying against piles, with rounds/teardrops this is impossible. Where I work we use/go through heaps of fenders, the round/teardrops are quick to deploy coming up to a pontoon & if set with the bottom just kissing the h2o generally wont climb out which the sausages will do at times.
    Main thing is that fenders are way cheaper than repairs so invest & save;)
    I'd say go four sausages & two teardrops and two fender boards at 4-6' long, we generally make them from some laminated timber scaffold plank and speed bore some lashing holes in them.

    Jeff.
     
  7. UpOnStands
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    UpOnStands Senior Member

    thanks for the detail.
    you also do not recommend the inflatables?
     
  8. waikikin
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    waikikin Senior Member

    usually get these in the blue ends & 450mm http://www.rwbmarine.com.au/?pProducts=ropeFendersMooring#1320

    & these in 620 & 700 http://www.rwbmarine.com.au/?pProducts=ropeFendersMooring#1317

    This is in a marina environment with heavy marine traffic, ferries etc pushing some surge through at 15-30 minute intervals plus passing traffic, the area. They come deflated & we just pump them up to just squishy enough. I think the costings are around 25 for the smaller sausage to around 50 for the size teardrops we get. Pretty sure they come from China or similar & about 2% are RS but that shouldn't be a retail purchasers issue & would have some margin on what we pay, to us they are just a consumable that's required to protect the vessels, but we do get a good life out of them.
    Jeff
     
  9. tspeer
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    tspeer Senior Member

    Four would be the absolute minimum. There are times when you will need fenders on both sides. For example, when rafting up with other boats, or going through locks. Then you'll need two on each side, and preferably one or two more.

    It also helps to keep at least a couple of fenders stored in each hull, so you don't have to rush back and forth swapping sides when you realize you'll need to moor on the opposite side from what you'd planned.

    On a related topic, you will need at least four mooring lines - bow, stern, and two spring lines. And you should have a couple of long lines (>50ft) for use in locks and for maneuvering with springs. For the same reason as the fenders, it is good to have a couple of mooring lines in each hull. Especially if you are short-handed, a breast line near midships will get you secured to the dock quickly, and then you can tie up the bow and stern lines at your leisure.
     
  10. UpOnStands
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    UpOnStands Senior Member

    great information but the cat is slowly sinking on its lines with each post.
    had to move the front double beds slightly and use the space for a 120 cm x .71 cm x 42 cm centerline locker.
    Seems like I'll need the storage space!
     
  11. waikikin
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    waikikin Senior Member

    Just lash a couple of the sausages to the forward tramp... make nice pillows/footrests while you're kicked back on autopilot listening to the dolphins squeal as they play around the bows..

    &... to save weight... let the air out;)..
    J.
     

  12. UpOnStands
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    UpOnStands Senior Member

    LOL
    Brings up another query for the community
    Auto-pilot remotes
    Wireless is really really dependable or should be wired? Seems to be pros and cons for both
    I was going to run a hardware steering extension to the front but complexity and weight go up and reliability goes down.
     
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