Difference between a deadeye and a clump block

[Captain Al]

Can anyone tell me if there is a real difference between a clump block and a deadeye?  Both 5mm and both 3 hole.  My kit calls for both but supplies only what appear to be deadeyes.  I can't really see how they are differentiated either in use or in appearance.  Since they don't supply enough anyway, I'm going to have to order some and I can't find a supplier of clump blocks but I can find deadeyes.  Is this really just a question of terminology changing over time?

[jbshan]

A deadeye is a circular fitting with (usually) three holes bored through the flat face.  It is mostly used in pairs to provide mechanical advantage for belaying the shrouds, backstays, etc.  A deadeye is 'dead' because it has no pulley (sheave).

A clump block is a block, with sheave, developed after 1840, used for fore-and-aft sail sheets.  (M. A. Edson, 1977, in NRG Shop Notes Vol I, p 166).

The best I can describe this is it is more ball-shaped than most blocks.

You don't say what your model is, but if it is before 1840 you could certainly use a normal block without fear of being inaccurate.

[Dan Vadas]

Al, what kit are you building? Some of these manufacturers use their OWN terminology for certain items (just to keep us all in confusion ).

 

I'd say just go with "deadeyes" for both .

 

 Danny

[Captain Al]

Thanks for the replies.  The kit is still the one I started 18 months ago -- A.L.'s Bounty.  Considering all that's been said, particularly that the real difference is that the later clump blocks had sheaves while the deadeyes just have holes -- the fact that most of the blocks used on models don't actually have spinning sheaves, I think Danny is right.  When I need to order some it'll be deadeyes.  Thanks again everyone.

[gjdale]

Al,

 

If you google the term clump block, you'll find both definitions and pictures. jbshan has it pretty much right in his answer above. A block is a very different beast to a deadeye. If the instructions are calling for a three holed clump block, then I'd suggest using an ordinary triple block (ie a regular block with three sheave holes side-by- side, not in the triangular pattern of a deadeye). Triple blocks are fairly readily available, including through Chuck's Syren site, or can be scratch made quite easily.

[jbshan]

Al,

 

If you google the term clump block, you'll find both definitions and pictures....

After Googling:

 

Deadeye-

Clump block-

This is different that the definition I found earlier, but both have the sheave offset to one end.

 

Deadeyes and clump blocks are not interchangeable.

[Captain Al]

GJ..., the way you put it makes 100% sense.  We're it not for some ambiguity issues I would easily see why you'd advise not to use a deadeye if it called for a clump block.  But consider this:  A.L. has also listed regular blocks (doubles as I recall) as "frames."  That one took me a few hours to sort out before I realized I was better off using the Spanish parts list.  Then there's the problem that while they "call for" both deadeyes and clump blocks, clump blocks is but one of many different ways they refer to a block, be it single, double, and now, using your logic, a triple.  There are no triple blocks in the kit.  I think the safest thing now for me is to assume that when they say "clump blocks" they are referring simply to a block (with sheaves) and not to a deadeye.  It may be that the so called "clump" is a single (as in your diagram), a double, or a triple (but that would probably not be the case or they'd really be amiss in not supplying any).  I am going to have to get better at following the rigging plans to determine exactly what type of block to use and how many sheaves it should have.  Going to the plans should make it clear though whether it should be a deadeye or a block.  This discussion has enlightened me in several ways, so thank you all again.

[hornet]

Every time I browse this site, I learn something new. LOVE IT

[JerseyCity Frankie]

Having never heard the term "Clump" block I googled it and found that there ARE definitions for the word floating around the internet, all describing an otherwise ordinary block that is "thicker" or "heavier" but I reject these as defining characteristics for a block since they are subjective. Blocks exist in many thicknesses and their thickness is not what causes them to fall into one category or another.

Blocks CAN be differentiated one from another by stating their size, the number of sheaves or the shape the block takes. You can have a Rope Stropped Block or an Iron Stropped block. There are Snatch Blocks, Bullet Blocks, Topsail Sheet Blocks, Shoulder Blocks, Long tackle or Fiddle blocks. But there is no "clump" block in any of the English Language reference books I have read.

My money says "Clump Block" is an artifact of translation.

[jbshan]

Having never heard the term "Clump" block I googled it and found that there ARE definitions for the word floating around the internet, all describing an otherwise ordinary block that is "thicker" or "heavier" but I reject these as defining characteristics for a block since they are subjective. ...

My money says "Clump Block" is an artifact of translation.

No, it's a real term, I have come across it before.  Please note the source I cited in my first post.  M. A. Edson is usually authoritative.

The sizes of the parts of a 'normal' block are laid out as ratios of the size of the rope/line that is intended to reeve through it.  That state of 'normal' is what the clump block is thicker or heavier than.

[Captain Al]

But in this case, the case of Artesiana Latina's misleading or ambiguous nomenclature, I have to go with JC's conclusion.  They simply did a poor job of translating from Spanish to English.  And it isn't the only time.

[JerseyCity Frankie]

....."A clump block is a block, with sheave, developed after 1840, used for fore-and-aft sail sheets.  (M. A. Edson, 1977, in NRG Shop Notes Vol I, p 166).".....

 

I found the page you mention with the list of Edson's blocks and I see the "clump Block" there. what sets those blocks apart are their lack of sharp corners AND their thickness. Edson says on page 169 that "...it was made thicker and stronger than an ordinary block and generally was oval in shape and could be turned on a lathe"......

When tacking,  an ordinary block with sharper corners can very easily hang up on a stay as you try to pull it across due to its more square shape. to allow the weather sheet to be more easily pulled over the stay in either direction when the ship goes about the best shape is a double ended cone. Underhill calls them "Bullet Blocks" and that is how I have always known them. Some of the better appointed tall ships of today have them, but they are rare in my experience.

I can see why a sailor would cal them Clump Blocks though since when the ship goes about, the headsails shake and slat about in fresher breezes as they come through the eye of the wind and this can cause the sheets to whip all over the place before they are taken up on the new tack, the pendant blocks on them can CLUMP pretty hard agains the deck or anyone out there under them as they flew around. Due to their constantly being smashed around I am sure they needed to be made stronger than an average block and thus thicker.

Incidentally there is no mention of Clump Blocks or Bullet Blocks in the Anatomy of the Ship Bounty by Marquard.

[figuerres]

sounds like translation here... if the  clump was created/named in 1840 even giving a couple of years it's way past the Bounty as that is 1780's many years to early for the term to be right.

.

[Bob Cleek]

A "clump block" is "a large single block with a wide swallow used for a variety of daily purposes on board ships.  They are made with a thicker case than the usual run of blocks carried in a ship so as to provide added strength to the purchases in which they are used."  [The Oxford Companion to Ships and the Sea (Oxford University Press 1976, Ed. Peter Kemp)]

 

Clump block: " Small, short, and thick  working block with a solid rounded shell and wide, squat sheaves and swallows.  it takes a rope half its own circumference in thickness." [Maritime Dictionary (Rene de Kerchove, Van Nordstrand Reinhold Co. 1961)]

 

I've always heard the same block as described above called a "thump block" or "tump block."  They are used as sheet turning blocks fastened to decks and rails and so mounted so the pulling force is upward, rather than downward as with many rigging blocks aloft. When the strain is off them, then, as when serving as a sheet block and tacking, they fall down onto the deck or whatever and go "clump," "thump," or if on a New England accented vessel, "tump."  Hence their name.  As they get banged around a lot and light weight isn't much of a consideration, unlike blocks hung aloft, they are heavily built.  A Turk's head laid flat to form a woven pad is often placed around the eyes to which "thump blocks" are fastened to cushion the impact when they "collapse" when tension is off them.  These are called "thump pads" or, I suppose "clump pads."

Edited May 3, 2015 by Bob Cleek

[Captain Al]

Interesting bit of history Bob.  Thanks for the post.

[Old Coastie]

On the USCGC Eagle the Turks Head mats were used under the blocks affixed to the deck to keep them from damaging the wood deck as they jumped around during sail maneuvers.  I don't recall ever hearing the term "clump block"  (which is why I'm reading this thread :)).  Mr. Bob Cleek's remarks make the most sense to me.  I'm building the MS "Niagara" and came across the term on the rigging diagrams, but it looked like it was a block attached to a pendant on a fore and aft sail.  Now I know it was attached to the deck, not the sail.  Also, something no one has mention so far; if you look at the diagram of a clump block, you can see that the shaft of the sheave is not in the center of the block as with most blocks, but offset towards the "sail end", not the "deck end", so the "holes" in the block (don't know the correct term) are not of equal size and shape.  I assume (a dangerous think to do sometimes) the sheet would reeve thru the larger hole, which help prevent jams.

 

I have another question.  What is a "sheet block"? Other than the obvious usage, the only difference I can see is that the "sheet blocks" I purchased from Syrene Models have a little curved "tail" on each end.

 

Thanks.

Edited November 17, 2018 by Old Coastie

[wefalck]

This thread is quite old and I don't recall having seen it before, neither did I recall ever having come across the term 'clump-block'. Intrigued I consulted my 1908 edition of Paasch's 'From Keel to Truck', which is the Five-Language-Edition. Paasch gives as Spanish translation for 'clump-block' the term 'vigota' and for 'dead-eye' the term 'vigota ordinaria'. When you 'google' for pictures of 'vigota', it actually shows you 'dead-eyes'. So there seems to be a bit of modern confusion between what the terms means. In all the other languages there is a clear difference - except for the Italian, where 'bigotta' can mean a 'dead-eye' and a 'clump-block'.

 

As to 'sheet-blocks': these have to noses at the upper end that are meant to prevent the sheet become wedged between the shell and other ropes. 

[druxey]

From the description, a clump block is what was earlier termed a 'thick' block. There were regularly proportioned blocks, as well as 'thin' blocks. The latter were, as implied, thinner for their length and were reeved with a lighter line than the regular version. Presumably 'thick' or 'clump' blocks carried lines of larger size than their 'normal' counterparts.