Quote:
Originally Posted by Boatsie
Besides putting up with an idiot (my clews and guys).
This picture is an unknown yacht.
If you were to build a smooth edge where the line is and ditto on port side. By using twin rode she'll ride swell much better. A reduced pitch fulcrum to reduce line snap. A reduced acceleration while on pick.
(Comparing to similar vessels via bow rollers)
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Indeed implement a smooth and wide radius for all turns of rode,
sheets, ropes and providing for reduced angle and mitigate against vertical movement so as to derive eased motion, those are key elements in harsh conditions.
As to the snubbers - "length yields", i.e., stretches under load. So longer snubbers work best and non-oversized diameter snubbers provide for added stretch. With a given load, a single snubber will stretch more then providing the same tension loads to two snubbers [bridle like configuration] and thus a single snubber can be more springy and softening of peak loading, BUT the given load is focussed to only the one snubbing rode which stresses such singularity of rode to higher levels of tension,
heating and chafe, and such configuration also focuses all the load to the single hard point attachment to the vessel [to a cleat] and to any routing devices through which it passes [chocks or anchor rollers]. The use of a bridle scheme allows for dividing the load to lessen the stresses to each component of the force pathways. Or in the alternative, where one uses one leg of the bridle system to be the primary and the second to be slackened to become the secondary [i.e., a storm snubber] or a "safety" snubber in case the primary were to break; but if a primary and a secondary snubber scheme is deployed recognize then one is again focusing the load foremost through the pathway of the primary snubber.
As to placement for anchorage, I suggest if harsh conditions are anticipated or arise to affix the snubber to the port and starboard mid-ship
cleats or hardpoints [or to hardpoints a distance back from the bow] as such readily avails use of yet longer snubbers and the forming of a gentler angle then progressing snubbers directly from and over the bow. The midpoint of a vessel does not pitch or turn with as much magnitude or velocity as the ends. [A reason to like
center cockpit vessels]. This midship directed snubbing method is rather obvious but seldom realized; yet any competent mariner deploys exactly such configuration when they tie up to the
dock in the marina - such ropes being called
spring lines. Emphasis added to the adjective
spring Note that bridles that ride on either side of the
hull also aid in keeping the boat from turning and sailing tro port and starboard as they tend to block and guide the boat into the
wind. When a boat
sails to port and starboard it inflicts very large turning moments onto a bow's structure potentially exceeding its yield strength resulting in bending the roller or
bowsprit to a side and downward.
Snubbers are Springs!!! One desires to not bend a spring instead one desires to allow the spring to linearly extend and
contract absorbing and releasing tension an work effort over a greater periodicity of time so as to avoid peak loading
on the hard points [the hardpoints being the anchor or
mooring at one end and the other where the line is affixed [e.g., a cleat] or where it is routed through or over, e.g., a chocks or hawespipe,
deck edge.
If one is afforded anchorage such as to be only subject to modest swells and waves then little cyclic peak loading will be realized so the type of snubbers and their pathway or pathways become lesser of
import as to fixing your vessel. Just as if your
docking berth in a sheltered marina has near glass smooth conditions, then there is lesser need for utilizing long spring lines or crossing your bow and stern lines so as to extend their length and lessen their angle of action. But if your marina is subject to occasional severe rollers and waves [as mine can be here in Montana] then one really needs to tie up for dealing with severe peak loading and significant vertical and sideways movements and implementation of load sharing and peak load lessening implements. There is nothing like watching a 10,000, 20,000 or 40,000+ pound yacht thrashing about in its slip when tied to short lengths of
docking lines. The entire dock shudders violently under the peak load of each and every wave. That's when you see boat
parts tear out or dock
parts tear out and lines chafe and break and when one line breaks free, the rest typically fail in rapid succession. I
recall in less than two minutes one boat broke out seven of its eight improper docking lines all because they were each too short and not properly lead or angled. The one remaining line provided the brief moment to allow our attaching of additional lines to wrangle the heavy boat back into it slip, else it would have drifted back into the downwind docked boats on the nearer to shore pier with likely devastating effect on the smaller boats in the shallower water.
I have come to truly hate the few days [and seemingly longer nights] when the
wind becomes strong, sustained and out of the worst direction for fetch length and exposure to the entry of the marina as then my marina can have two or three feet of swells rising above, over and through the fixed level dockage and then lowering similarly far below [so say six foot total vertical
displacement movement from peak to valley]. One moment the waterline of a boat may be equal to or higher than the dock, then depending on the size and height of the boat, the deck is near equal to or worst case lower than the dock. The dock being something you so do not want to have a boat get under or on top of. The bowsprits that may partly overhang the main dock because of a too large of a yacht situated in a too short of slip become truly lethal as they rapidly rise and drop and / or they get quickly busted off when they collide with the top of the dock; bye bye anchor roller and then dangling anchor smashing the side of the bow. In the dark I turned my back on a bowsprit once and almost stepped under the bowsprit with its two large anchors which would have squashed me like a bug under a shoe. I've spent considerable time readjusting and replacing the dock lines of unattended or improperly tied yachts, especially those with appendages [bowsprits or
davits or swim platforms] are prone to riding under or over the dock. Having to shift a large boat further out of its berth slip so as to have its bow or stern shifted away from the dock when it is being severely tossed about is difficult and hazardous. One has to first attach additional retaining springlines to the bucking bronco of a boat, loosen the stern and bow lines that are intended to restrain sideways motion, loosen the springlines that disallow the boat to shift out of its berthing slip, then tighten the added spring line to pull the boat outwards from its berthing position, then reset the bow & stern lines to inhibit excess sideways motion and then reset the backwards motion restraining spring lines. Running back and forth on the finger piers, or worse dealing with pilings on one side when there is no finger pier on that shared berthing configuration, accomplished usually alone and sometimes in the dark at night. Then when having run out of spares ropes, the situation calls out for a quick trip to the
chandlery or
hardware store to
purchase yet more ropes to settle other unattended boats. I have learned to just buy out the local stores stock of ropes in such "emergency" situations and return whatever I might not use after the storm. I have also wised up and learned that it is preferable to buy out the inventory of lines of various size and length before the storm arrives and go about affixing the lines to boats that need them before they begin severely tossing about. The most recent severe storm the marina manager, his resort staff, a deputy Sheriff and several Search and
Rescue volunteers aided in wrangling the wayward boats in the marina, before I even recognized that a storm had arrived and was able to get to the marina. So upon my arrival I was much relieved to see competent and capable personnel getting ahead of the situation for the first time. And hey, sometimes I actually get refunded for the cost of the lines I supplied by such wayward boat owners if and when they notice or find out their boat has been provided new or additional lines. Usually not
. It's not like I affix my name and contact information to the new lines or go ask them for $$$. Some people have said that I might incur liability for interceding and adding or adjusting lines, if bad things arise, but I just say, Bring it on. I will trust the judge [a friend] and a jury to know a good Samaritan. I am much more worried about getting hurt trying. The sturdy docks in the marina reveal the accumulated scars of bashing boats and replaced
cleats. Each scar has its own story, some of the scars can be matched to the scars on the boats.
One time the owner of the yacht adjoining mine in the marina was watching the TV evening news and there was a live broadcast report from the marina reporting on the issuance of Lake Wind Warning and the huge swells and white capped waves that the lake was tossing up and the marina was a perfect spot to film such Nature's fury because the waves were overriding the hefty rock breakwater [and even eroding through parts of it] and tearing up a lot of the portion of the sheltering metal and
wood break water such that there were large timbers floating about in the marina and the boats were rocking to and fro thereby making for dramatic filming. I did not notice that the T.V. reporter and film crew come out to the end of the dock where my sailboat shares a berth with an adjoining yacht and I was at that moment standing on the swim platform of the adjoining boat attempting to place a line through my chain tie off positioned on the shared stern tie piling so as to secure a line to the adjoining yacht's stern. With each incoming swell the swim platform would submerge soaking me, all the while I was holding the rail of the adjoining yacht with one hand and trying to reach far out to slide the line between my chain tie and the piling without injuring my hand. The non-line fixed stern of the adjoining boat was rocking and riding up and down about five feet and yawing considerably as the uninhibited swells were from the stern's quarter. Apparently it made for pretty dramatic live action of which reporting I was oblivious until I returned some minutes later to the main dock, where the report interviewed me for continuing reporting. I got to see an edited and shortened taped rebroadcast at the 11 o'clock night news. It was a "Hey, that me! moment." The owner of the adjoining yacht that was watching the evening news, did not realize there was a severe storm at the lake with winds coming from the worst direction and length of fetch possible and was seeing that his boat had broken loose and was riding alternatively on top of the dock and then crushingly under the dock, snapping cleats on the vessel and on the dock and breaking lines. You can imagine his shock and anxiety, then partial relief seeing that someone was attending to his yacht and successfully resolving its adversity. My primary [read, selfish] motivation was to keep his adjoining boat from smashing towards and into my properly tied boat in the shared berth arrangement; there being no protective finger pier between our boats. When the adjoining yacht owner and I finally meet up near the end of the season, he recognized me from the TV broadcast and expressed much gratitude for my actions and returned the lines that I had deployed to properly tie up his yacht of which his boat used for the rest of the season.
It is not rocket science, it is merely basic physics and evaluation of forces and of mechanical engineering and material properties. If the forces at play are not major then the method and materials can be less forgiving and be readily capable of taking up the comparatively modest challenge.