Cargo tie downs

[Osmosis]

I am currently building the San Francisco Cross Section. I am getting to the point where I will be gluing down the middle deck and I was wondering. Would there have been rings or eye bolts permanently installed in the cargo hold deck or bulkheads for lashing down loose cargo? If so now would be the time to put them in. The instructions don't call for them but if they would have been there it is an easy enough detail to include. The kit does include crates and barrels and spare billets of lumber to put in the hold it seems there would be a way to tie them down.

 

Thanks

[wefalck]

I don't know what ship the SAN FRANCISCO was, neither what era. Assuming that it is a 19th cargo sailing ship, I think normally cargo in the hold would not be tied down, but rather 'wedged in'. This means that smaller items of cargo and lumber would be put in such way between the larger items that nothing can move. Apart from preventing items from moving this also maximises the cargo volume use. In the old days ships sometimes had to wait for considerable time to complete their loads. This not only for economical reasons, but to increase safety - a half-loaded ship with the risk of a shifting load can be in great danger in bad weather. It was the art of the loading masters in the harbours and of the first mate to stow the cargo in a safe way.

[rybakov]

Hello

 

I don't think there would be any eye bolts because the cargo would have to be dragged  across

the deck to the opening of the hatch to be lifted out.

At least on iron hulled ships there were clamps on the sides on wich  heavy boards running fore and aft

were inserted and wich provided anchoring points for lashings. the cargo would be held againt the sides.

To complement the lashings one would use beams cut to size and wedged between crates to further immobilize the cargo.

 

There's more to it but that's the general idea

 

hope that helps

 

Zeh

 

[mgdawson]

Hi Art

 

I’m guessing you’re referring to the SS San Francisco 1853, wrecked on her maiden voyage, Jan 1854.

 

As Wefalck indicated, the preferred practice in that era was a tight stow rather than relying on lashings. In my experience tight stowage is far better in a seaway, i’ve been in situations in a gale where we’ve had seamen retightening lashings every hour and the cargo working against them still snapped chains and stretched 20mm dia wire rope. A tight stow can’t move.

 

Towards the bottom of this page (http://mcjazz.f2s.com/ClipperShipPlans.htm) is a drawing of a tea clipper being loaded. As you can see they have multiple sized tea chests to use the maximum volume and fill the nooks and crannies with stone dunnage. There’s a labourer with a large mallet to ‘encourage’ the chests into the tight stow. Not quite the cargo your SF would have carried but the theory’s there.

 

Note :- Most if not all the drawings on the linked page were drawn by George Campbell and appeared in his book ‘China Tea Clippers’ (1974).

 

 

Edited October 31, 2018 by mgdawson

[Osmosis]

Thanks for the quick replies.

 

I do apologize, I should have been more precise in my description. The ship I am modeling is a 16th-17th century Spanish Galleon.

 

Regards

[Roger Pellett]

I agree with the above, cargo was shored to prevent it from shifting, not tied down. The material used to shore cargo was and still is called dunnage.

 

Everything that could be reasonably shipped in barrels was.  Barrels were strong, watertight, and their shape when closely stowed prevented some resistance to shifting relative to each other.  Barrels could also be knocked down and reused. Wedges called coates were driven at strategic points to prevent shifting. 

 

The heaviest and least valuable cargo cargo was placed deepest in the hull.  A layer of plant material could be spread over the ballast to act as a cushion.  Remnants of Spanish heather used as dunnage have been found in the remains of the Newport Medieval Ship sunk about 1470.  Barrels would have been stacked in tiers clear to the bottom of the hold beams of the deck above to further limit their ability to shift. For this reason,the vertical distance between successive  decks was limited to limit the number (and consequently weight) of tiers that could be stacked on each deck. 

 

The best  analysis of loading a ship of the period that I have found is contained in the analysis of the Red Bay Wreck, a Sixteenth Century Spanish Galleon found in Red Bay Labrador.  “The Underwater Archeology of Red Bay”  five volumes published by Parks Canada includes a lengthy description of cargo loading.  The Red Bay Ship carried a homogeneous cargo- whale oil, but the principles of loading a cargo that would not shift or jeopardize the stability of the ship are unchanged.

 

Roger

 

 

 

 

 

 

Edited October 31, 2018 by Roger Pellett

[Osmosis]

Thank you all again for the replies. It looks like it is unanimous, No Tie Downs. Once you give it some thought there are some very compelling reasons for not having them.

[David Neisen]

I have heard that coconut fibers were used as dunnage.  Is that true?  I understand coconut fiber is made into coir and used for cordage, mats & bedding, and flotation - but it seems not a good product to reduce shifting or protect cargo from moisture, as it can absorb 8x its weight in water.  Plus, when wet it leaches tannins which could stain other cargo.  I also understand the value of coconuts themselves to sailors - but it is the coconut husk/fiber processed into coir (for internal box packing) that I am asking about.  Thanks for any responses.

 

[wefalck]

My knowledge of the coconut trade is limited, but my understanding is that it is waste product from copra production. I didn't check, but I am rather surprised that the fibres should absorb so much water, given the fact that mooring and towing ropes are made from coconut fibres because such ropes float.

 

Staining of cargo probably is not issue, as goods for sea-shipment would normally be sufficiently wrapped.