Conference unifix::sailing

Instead of a cage, how about one of the line cutters that fits on the 
propeller (moving blade) and on the shaft strut (fixed blade)? They are 
stainless steel, however. A propeller cage would, I suspect, 
considerably reduce sailing performance, especially in light winds.

Does anyone have any personal experience with these line cutters? I am 
considering adding one to my boat to reduce the hazard of lobster pot 
warps. 

    Line cutters may be alright for some, but not in my case for two
    reasons; 1) I don't have room on the shaft to install spurs, 2)
    I have too much respect for those who try to making a hard living
    from the sea to use a method thta would damage their equipment.
    You see, Cape Porpoise is a working harbor of some 50 -60
    lobster/fishing boats and only 10 or 12 pleasure boats.
    
    Yes, a cage will reduce my speed by .25 knots. This is not a great
    deal Alan. It is something I can live with. In light airs, if I
    can't really make much headway, then I'll have to start up the iron
    sail.
    
    Thanks
    
    Paul

    
    Some of the lobstermen may have cages fitted on their own boats.
    Maybe one of them can tell you were they had it done.  Try checking
    out the boatyards near Cape Porpoise who service the lobster boats.
    
    - gene

re .2:

>>>    I have too much respect for those who try to making a hard living
>>>    from the sea to use a method thta would damage their equipment.

I agree with you philosophically, but ..... practically, I would prefer 
to minimize the risk of losing my boat due to lobster pot warps, etc. I 
used to think that being careful to avoid pot warps was enough. Not any 
more. Last September we were reanchoring around midnight to avoid a lee 
shore (major wind shift) and backed over two warps which tangled around 
the propeller hard enough to pull the shaft from the transmission 
coupling. Fortunately, by this time the anchor had set, but we still 
spent an extremely nervous night worrying about the nearby ledges
knowing we had little chance of avoiding a catastrophe if the anchor
dragged. 

Some of the lobstermen are really quite thoughtless in how they set 
their traps. I really don't see why some Maine lobstermen think a 50 to
100 foot toggle line is needed from the main bouy to the little bouy
(usually virtually invisible) on the main pot warp. A much shorter
toggle would be adequate and much safer for everyone. Cape Porpoise is a
nice harbor (we've sheltered there several times), but the lobster pot
bouys make the entrance non-navigable as far as I'm concerned. I won't
go there again except in desperation. In general, I'd like to see 
lobstering banned inside harbor limits and in harbor entrances. I doubt 
it would reduce the total lobster catch one whit. (According to the new 
Maine cruising guide, the total lobster catch in Maine has stayed the 
same over the last 50 to 60 years in spite of a 10-fold increase in the 
number of traps.)

    I am about to fit spurs to CIRCE. Last season we fouled 8 times......
    The rationale is that the amount of debris in the waters of the English
    Channel make it worth while. Thats the rationale the real reason
    was after one fouling last summer. We had sailed a 20 hour overnight
    passage across the English Channel to Alderney and the wind dropped
    so being 2 miles off Alderney we decided to motor in. We headed for
    the harbour and fouled badly. Luckily the wind got up again but
    it took us several hours to sail into harbour and pick up a bouy.
    It took two divers off a neighbouring Tri 20 minutes with tanks
    on to clear the prop, all for the price of a bottle of Wine.
    Alderney is very rocky and at Springs the tide can run at 6 knts,
    we were at Neaps so all we had to sail against was 4 knts. Needless
    to say I was on the radio to Alderney Harbour to keep an eye on
    us........ Many of the fishermen are laying their pots and badly
    marking them in navigable channels. The advice to fit spurs came
    from a fisherman......who believes that badly marked pots are a
    menace to all.
        
    I also don't have room to fit the Spurs between P Bracket and prop
    but the kit comes with a Spacer to resolve the problem. Cost on
    my 28 footer is 190 pounds stirling.
        
    Pete                 
        

It's illegal to obstruct a marked channel, and where otherwise 
posted (i.e., certain specified anchorages), by anchoring your boat or a 
surface buoy.  It doesn't take any special skill or talent for anyone, 
including fishermen, to learn what the law is.   I respect most fishermen
of all types, but those lobstermen who violate the law for their own
convenience and substantially interfere with others -- or worse yet -- put
them in danger, deserve to face the "inconvenience" of losing some traps. 

Outside marked channels, I will respect their property and give much extra 
effort to save their gear if I tangle in it.

J.

(Maybe these propshaft cutters are what the fisheries conservationists
should sponsor as the way to preserve the population of Homarus Americanus!) 

    Re base note and follow-up
    
    It sounds like you already give due respect to the lobster"persons"
    of Cape Porpoise.  Adding a cage may in fact make things
    worse.  If you add a cage, I'd guess your speed would
    suffer a LOT more than .25 knots.  I've never seen statistics,
    but any cage that can sufficiently protect against fouling would,
    I suspect, slow you the better part of a knot in all but the 
    most blustery conditions.  So you'll be motoring in and out much 
    more often.  If you take any pleasure in the seamanship required 
    to handle a boat exclusively under sail, this would become intolerable.
    
    I really think you can find a "knife" that will fit.  I'd continue with
    your old practice and be content in knowing you've done your
    best to respect the rights of others while preserving your
    rights as well.
    
    Dean

    Any info on the relative efficiency of the two options?
    
    Id guess there are many ways a line could foul a prop- like around
    a blade- that would not be cut away by a shaft mounted cutter. On
    the other hand, I see little way a line could get inside a reasonable
    cage.
    
    The cages Ive seen have been made of about 3/8-1/2" dia rod. I cant
    believe this would create much drag, certaily not enough to kill
    a knot off top speed.
    
    Id go for the cage.

Sorry, Ron, but I have to disagree. A prop cage is almost perfectly designed
to produce the maximum drag for the least amount of material. Here you have
a collection of round rods (a cylinder produces more drag than any other smooth
shape, it approaces a flat plate) welded into a lattice that guarantees lots
of interfering vortices to generate turbulence and suck up energy. I would
expect a cage to produce as much drag as a fixed-blade prop or even more.
A knot off top speed wouldn't surprise me at all.

As a compromise, you could see if someone could manufacture a shroud for
your propeller. This is a ring which has an approximate airfoil cross-section,
and which fits around the outside of your propeller with maybe 1/4 to 1/2 inch
clearance. It would be more expensive to make, but produce much less drag and
be almost as good keeping line out. The bonus would be some increased
thrust from your prop. both forward and reverse.

Ross Faneuf

    Before deciding to go the cutter route I had a long chat with a
    firm of very reputable Marine Engineers ie they do work for our
    MOD as well as civvy boat owners. They favour the cutter because
    of the diverse rubbish you need to protect against ie sheets of
    polythene, polythene bags ala supermarket, japanese weed, pots,
    etc. They also believed that a cutter would cost me .25-.5 knt but
    a cage would be 1.25-1.5knt. Of the 8 fouled props last year 2 were
    in a navigable and crowded channel, 3 were sheets of polythene just
    below the surface.....,2 were Japanese weed, 1 was someone elses
    warp that was left trailing behind their motor yacht (They did offer
    to go over the side to free it, I readily accepted.....).
    Hence I am fitting a cutter.
    
    Pete

    What are the prices for the cutters?
    
    thanks
    
    Paul

RE: .9,

>>>  As a compromise, you could see if someone could manufacture a shroud
>>>  for your propeller. This is a ring which has an approximate airfoil
>>>  cross-section, and which fits around the outside of your propeller with
>>>  maybe 1/4 to 1/2 inch clearance. 

I've seen a similar type of thing fitted to some fishing boats, especially 
further south; it's apparently call a Kort nozzle.  They use it primarily 
because is increases the thrust dramatically at lower boat speeds, as when
dragging or towing nets. 

One problem lies in how efficient your propeller is relative to moving 
your hull; if it moves a large volume of water with relatively less motion 
of hull, then you'll find lines can be sucked into the blades from a 
distance outside the expected path of incidence.

If you're set on a cage, consider a very simple one:  only three, four or 
five rods in front of the prop instead of the full cage you often see on 
lobster boats.  Remember, they're moving forward and back at all speeds 
while turning amidst many lines.  And they tend to operate like a dragster 
-- full throttle or idling out of gear -- so the likelihood of sucking in 
a line from a short distance away may be greater.

J.

re .11:

The Spurs line cutter prices vary with shaft size. I don't have the 
current price list, but a cutter for a 1" shaft is about $200 to $250. 
H&H Propeller in Salem, MA, sells them.

    Just as a follow-up to my base note.
    
    Last year, the Coast Guard took two patrol boats (44 footers) and
    strung a cable between them. they then entered the main channel
    and harbor of Cape Porpoise and swept the channel on two different
    dates. The went up to one of the islands in the harbor and dropped
    all the pots and buoys they had removed and told the lobstermen
    to go ahead and look for their equipment but to keep them out of
    the channel and harbor or they (CG) would be back.
    
    The lobstermen didn't, the Coast Guard did. By September and October,
    the channel was in pretty good shape with only a few buoys where
    they shouldn't have been.
    
    I wonder what they will do this coming season?
    
    Paul

Doesn't Cape Porpoise have a Harbormaster?  If so, does s/he have *any*
teeth at all?  In Rockport, MA the Hbrmstr pulls traps in the channel on a
regular basis (where they wander over the line marking the channel limit.)
State law protects him from damage liability in doing so. 

J. 

    Cape Porpoise does have a Harbor Master. He is a Deputy of the Harbor
    Master of Kenneybunkport. The Cape Porpoise Harbor Master's main
    job is running the Cape Porpoise Fishermens Co-Operative.
    
    Although he is a fine person, you can't expect him to pull traps
    of those that are where they shouldn't be. In other words. One dosen't
    bite the hand that feeds you. He is hired (appointed) by the members
    of the co-operative.
    
    aul

    The CG probably has enough teeth.  
    
    Lobstermen in Mass and probably elsewhere are frequently armed and
    dangerous, i.e., shoot first and ask questions later if they see
    anyone touch their traps.  Enough so to scare off a lot of harbormasters.

    If I ran afoul of a lobster trap line, I'd leave the boat there
    and buy a new one    :-)

    Maybe I'm insensitive to others source of income, but I routinely
    cut the floats off of any traps that end up with the float bouncing
    up against my hull while at the mooring.  I just don't have the
    thousands of dollars to repaint my hull every year.  Traps don't
    belong in the harbors, nor in channels.  Plus, you hardly ever hear
    of people being killed by these guys anymore :^).
    
    Dave

    There is some commercial lobestering goin on in Newport (RI) harbor in
    the anchorage area and over towards the Admirals dock. Last year an
    acquaintence of mine anchored on two hooks with line. He found that
    a lobsterman had cut one of the rhodes to retrieve a pot that had 
    gotten tangled. He switched to chain and went and cut many of this
    fellows pots in the area off Ida Lewis...  I did not see any activity
    after that by the lobstermen
    
    Don