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While keeping up with what lambsbk is doing with his hawse holes and the breast hook, it made me to wonder about the use of the configuration of those hawse holes and capstan to hoist the anchor. Would work well to take in the scope but when the cable became almost up and down, the angle at the hawse would act as a brake and the sharp turn would damage the cable. When the cable reached an almost up and down position was the capstan secured and the lift taken over  by the cat rigging using stoppers to reset the lifting block to the cable after each two blocking of the rig?

jud

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Mark, thanks, I had seen that before and it bothered me then, it is only a solution to taking in the cable when the cable is lead out ahead of the ship, be a good way to move the ship against the wind or current until it was near the anchor. When the cable was up and down, the cable coming outboard of the hawse would bend down 90° when tension was created by the capstan pulling against the anchor that would have been under the bows, creating the up and down position of the cable.  More  modern hawse pipes  that lead the cable outboard from the powered capstan outboard do not allow an angle to develop as a hawse leading horizontally outboard does when the cable is up and down. That cable being pulled around that sharp angle would not only act as a brake but would damage the anchor cable. My question is, what was done to overcome that problem. I suspect that the cat was used to do all of the vertical lifting when recovering the anchor.

jud

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Hi Jud

 

When you start heaving the anchor you're trying to get an object weighing about 1500 tons moving.

That's the moment the chain or cable is under the greatest stress, once you get the ship moving it's easy.

When the anchor is up and down you have to contend only with someting like 3 tons, unless the anchor is fouled 

on the bottom, that bend really acts as a brake, but is not under enough stress to damage the cable.

As an aside, on ships with weak anchor winches or capstans we would go dead slow ahead as we started heaving to

overcome the inertia of the ship then stop  and let the capstan carry on.

 

The cat can only be used once the anchor is out of the water so that the tackle can be hooked to the anchor and the main purpose 

is to move the anchor from the hawseholes (where it would eventually end) to the side of the ship to then be stowed.

 

 

All the best

Zeh

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There was no way to reposition the cable to the cat, and (particularly on larger vessels), the messenger was below deck, not on the upper deck with the cat. As Zeh pointed out, the cathead was for final stage as the anchor cleared the water for stowage.

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I think one gets easily tricked by the fact an iron anchor as a very heavy object. 

 

Just some thoughts to jud´s interesting question: The cat hook is to be hooked in as soon as the ring breaks the surface. This can be seen nicely on the famous picture of the Royal Sovereign with the little man standing on the anchor´s stock handling the cat block´s hook.

 

At this moment the weight of the anchor is far less as it is not its weight of iron but only the one of the displayed water, which is - if I am right - 1/7th of the weight of iron. Afterwards the cathead, cat tackle and all the other rigging parts of the fishing rigging have to take the whole weight of the iron.

 

As the ship is always drifting with wind and current, the anchor cable always will have a certain direction a forehead. The ship should neighter run over the anchor, so a turn backwards of the cable was less favoured. Also breaking the anchor was often done by the big boats means there should usually not be the pull spill-hawse-downwards. 

 

So the pull downwards is far less than expected imho, but I do strongly believe, that a ship an a long cable, especially in a strong gale, will pull with a multitude of the anchor ´s weight. So it makes for me perfect sense to have the hawsers horizontal for that case, means in the direction of the ship pulling on the cable and having the minimum of breakage risk or chafing in those moments :-) 

 

XXXDAn

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Stoppers could have worked while re positioning the lower block on the cable. Have knocked the keepers off of pelican hooks holding the anchor chain and have been at the capstan when hoisting the anchor, taking in the chain when unshackling from a buoy, taking a strain on  bow lines and even used a capstan once to pull a 40mm gun out of battery. The hawse hole, chocks or blocks were used to lead the chain or lines to prevent sharp angles in all of the above. Have pulled rope around sharp angled corners and know what it does to the rope and if wood, what happens to the angle point on the wood itself, chains usually hang up in such conditions, so my question is based on experience. The hawse holes on the Constitution and ships so rigged would destroy themselves and any cable pulled through them with any strain at a near 90° angle, even a light load would do it, something missing in how the evolution was accomplished. Those old boys went to a lot of trouble to use blocks, bits, guides and fraping gear, to prevent damage to all their running and standing gear, the same care was also needed for the anchor cable and chains, those needs resulted in changes in how the hawse pipes were used to lead the cable, 'chain', out of the ship. Not a light question for me, I see a problem and I wonder how it was addressed. Have thought through how I might do it, but that is not the same as doing it or hearing from someone who actually needed to lift an anchor with that gear and hawse hole configuration. Not worth arguing about, but will continue to wonder how the anchors were lifted, I have a strong suspicion that the whole picture has not been reveled yet.

jud :) :)

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Hi Jud

 

I agree that there's a lot of chaffing in the the final meters or feet but I think that would not be much more than the wear

from the cable on the bottom to and fro as the ship keeps swinging. I recall reading somewhere (can't place it right now) that

the part of the cable nearest to the anchor was reinforced to resist chaffing on the bottom, which would also protect the cable in the hawse.

 

 I stand corrected on my thoughts about the force necessary to start the ship moving according the the link bellow, it  seems that

they used "dead slow ahead" too.

 

https://books.google.pt/books?id=4bYoCwAAQBAJ&pg=PA88&lpg=PA88&dq=hms+victory+dimensions+anchor&source=bl&ots=3wfmia38p4&sig=b6wZodd96O1ObvDaZwQ8e2cOiw0&hl=pt-PT&sa=X&ved=0ahUKEwjfoumRwpvNAhXMiRoKHXNHAJkQ6AEIYjAM#v=onepage&q=hms%20victory%20dimensions%20anchor&f=false

 

pages 89 and 90.

 

On page 91 I would rather say the cable paid out to be three to five times the depht of water depending on the type of bottom

and weather conditions.

 

I would say they were very much aware of the problem you raise, so much that as soon as they could place the hawseholes in a less awkward 

position (as we now have them placed) without compromising the strenght of the bows they did - iron construction.

 

Zeh :)

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It may be worth a read of the process for "Getting up or Weighing an Anchor" published in Steel, D. 1795. Seamanship, Both in Theory and Practice. Printed and published for, and at, Steel’s Navigation-Warehouse, Tower-Hill. docs.lib.noaa.gov/rescue/rarebooks_1600-1800/VK541S81795.PDF. 

 

The description begins on page 154.  It is fairly brief, reflecting the process previously described (raise using the hawser until the anchor is clear the water then catted and fished).  He also describes using additional mechanical means when necessary:

 

When the strain is so great as to require other purchases, the top tackles may be used thus : The double block is lashed to the main-masl or topsail-sheet bits, the treble block is lashed on the cable, and the fall brought to the capstern. If the top-tackle falls are thought insufficient, any hawser may be used that will reeve through the blocks.

 

 

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I am not sure if it is relevant to the discussion, but I wanted to point out that it is not the weight of the anchor which secures the ship.  Rather, it is the flukes of the anchor digging into the seabed (or lakebed) that does the work.  The cable is paid out to allow the anchor to lay almost horizontal...the design of the anchor does the rest.

 

When the anchor is set, hauling the anchor in does not bring the anchor to the ship.  It brings the ship to the anchor.  Once the cable is up and down the flukes break free from the bottom and the anchor can be raised.  Sailing or driving the ship to the anchor allows the cable to slacken and puts less strain on the cable.

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Agree with all that has been noted, the cable let out beyond the depth was and is called the scope and it is there to force the flukes to dig in, bringing the ship over the anchor while hauling in on the cable will lift the stock and pull the flukes free of the bottom. It is from that point that I question and still do, something is missing in the lift, not the hauling in of the scope. Granted, exceptional measures are taken when the anchor is snagged on the bottom and sometimes the cable was cut, not questioning those things, only the everyday lifting of a anchor that is on the bottom ready to begin the vertical lift part of the recovery. When an anchor cable becomes so large it can't be used on the capstan without damaging it, why would a sharp angle on the outboard side of the hawse be OK? Thanks all.

jud

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Jud,

On the angles... the hawse holes were not typically parallel to the water or decks.  There is an angle downward from inside to outside which seems to have varied depending on country, shipyard, etc.   The hawse holes were also lined with lead to ease on the chaffing and wear and tear on the ship and the cable.  And lastly, somewhere I read that in hoisting the anchor, there was some greasing of the hawse holes/cable... but I'm sure how common that was.  It may have been anecdotal for one incident.  When I remember where I read it, I'll dig it out.

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Jud I don't how relevant this is as it's not a contemporary source, but I recall learning about cordage diameter to bend ratios when I was in the corps. So I've searched and found this in the  'Rope User's Manual', page 38. http://www.samsonrope.com/Documents/Rope_Users_Manual_WEB.pdf. It's not specifically talking about ship hawse, but suggests a minimum bend ratio of 1:3 for bitts fairleads and chocks.

 

Dashi

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Good source Dashi. For modern fiber rope I cut and pasted the following from page 38;

A B C
D
SECTION C
:
ROPE HANDLING/USAGE
PAGE
38
BENDING RADIUS
SIzING THE RADIUS OF BITTS, F
AIRLEADS, AND CHOCKS
Any sharp bend in a rope under load decreases its strength and may cause premature damage
or failure. In sizing the radius of bitts, fairleads, sheaves, and chocks for best performance,
the following guidelines are offered:
Where a rope is deflected more than 10 degrees around a surface (i.e., bitts or chocks), the
effective diameter of that surface should not be less than three times the diameter of the
rope. Stated another way, the diameter of the surface should be at least three times the rope
diameter. Even larger diameters would be better yet because the durability of the rope increases
substantially as the diameter of the surface over which it is worked increases.
The ratio of the length of an eye splice to the diameter of the object over which the eye is to
be placed (for example, bollard, bitt, cleat, etc.) should be a minimum 3:1 relationship (larger is
always preferred to improve durability). By using this ratio the angle of the two legs of the eye
at its throat will not be so severe as to cause a parting or tearing action at this point (thimbles
are normally designed with a 3:1 ratio).
 
So a modern 4" diameter cable, ( 2r π; [ 2 + 2 x π = 12.6" cable ] ),  should be lead around a minimum of 1 foot diameter lead, but the larger the better. Makes sense to me, the ratio would probably be double with vintage fiber cable. Reason for my discomfort with the accepted description of raising an anchor, there is more to the story.

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Again, take a look at Steel - he describes the stowage of the rope as well as how to secure it whrn anchoring.

 

While it may seem counterintuitive based on modern useage, it was impossible to move the anchor hawser to any point other than the hawse holes once the anchor was attached. It was also not likely the cathead was used as it was not equipped to handle that size of hawser.

 

I may not be understanding your question, though - are you suggesting that the anchor hawser was not led through the hawse hole for weighing, as I have read it, or something else?

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No Wayne, I am not suggesting that at all. I am wondering how the sharp bends in the anchor cable were avoided or eliminated when the up and down part of the cable recovery was being done. So far, I have seen only some small gains in reducing the bending problem suggested, I think we are moving in the right direction though. Tilting the hawse down, lining it with lead and greasing it would aid in reducing the brake effect of a bend in the cable entering the hawse and help prevent damage to the hawze itself. Bolsters would help a little, they would contribute a lot in avoiding a sharp bend in the cable if they were used to help hold in place, some sort of temporary radius placed over them to ease the angle where the up and down cable was entering the hawse, that could be a viable solution. As far as using the cat for a vertical lift, those sailors were well able to use lashings to attach the lower block to the cable and then lift to the two block position, then stoppers could hold the cable while the lower block was re positioned on the anchor cable for another lift, not the most efficient method but well withing the capabilities of the the seamen and the cat gear. Doing it that way would produce a large slack bow in the anchor cable that could be pulled inboard through the hawse hole as the anchor was lifted. Maybe the answer was hidden in the gear stored below in the Constitution that no one could identify, or figure out what it was used for and had it all removed from the ship some time ago. We should all accept the fact that the seaman of old did everything within their abilities to prevent unnecessary damage to ship and gear. Hauling a cable under tension around a sharp angle would be something they avoided, even if the writings do not explain how. I see lots of critical parts left out of the written descriptions of gun handling so I expect to see such oversights in other writings preserved from the past, just because it is not covered in writings yet discovered, a problem existed then as it does today with pulling lines around sharp bends.

jud :)

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Thanks to all who have contributed to this discussion !  I have learned a couple things not previously known to me.  That learning experience is one of the hallmarks of this site.  Both seasoned builders and novices contribute to the site.  Keeps me coming back sometimes multiple times in a day, just to see what I might have missed.

 

Tom

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Besides tilting the hawse holes down and lining them, the French sometimes put rollers under the lip of the holes. Most often in larger ships, but frigates got them as well. Bolsters (bull noses) were common if they didn't use rollers.

 

post-1377-0-59131800-1465649496.jpg

 

Ciao. John

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With regard to dafi's post above two opposite forces act on a submerged object. Gravity equal to the open air weight of the object is pulling it down. Buoyancy equal to the weight of the the water displaced by the object is pushing up. The force on the anchor cable is therefore equal to the net of these two forces.

 

If water is one seventh as dense as wrought iron, then the force on the anchor cable after being broken out is 6/7 not 1/7 of the anchor's weight.

 

Roger Pellett

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