How yards were prevented from axial rotation?

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Y.T.

Y.T.

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Hi. This question bothers me for a while but I can’t find the answer. How the yards were prevented from axial rotation? I am looking at attached pictures and see no means that would keep the yard in position shown. Especially with auxiliary booms attached up above yards at 45 degrees from vertical. These booms by gravity want to turn the yard around it’s axis. It would be natural for booms to hang right at the yards bottom in order to prevent yard from axial rotation. Any thoughts?

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Really a good question

Slightly you can see the truss in you skecth with which the yardarm is pressed against the mast - to gether with (often) octagon shape of the yardarm enough friction is produced, that the yardarm is not rotating - this would be my explanation

1626476666438.png Jeers.jpg

Dutch Parrel rigging from Prinz Willem.jpg

There are a lot of different forces produced by the sails, rigging ropes etc. which are pulling and pushing a yardarm - but on a sailing ship everything also the yardarm is fixed towards the mast by friction
 
Uwek said:
Really a good question

Slightly you can see the truss in you skecth with which the yardarm is pressed against the mast - to gether with (often) octagon shape of the yardarm enough friction is produced, that the yardarm is not rotating - this would be my explanation
Click to expand...
Uwek said:
There are a lot of different forces produced by the sails, rigging ropes etc. which are pulling and pushing a yardarm - but on a sailing ship everything also the yardarm is fixed towards the mast by friction
Click to expand...
This is a very good answer, Uwek. Thank you very much. Which book is the second page from, can you please advise? The one with B,C,D,G,F examples.
 
Y.T. said:
This is a very good answer, Uwek. Thank you very much. Which book is the second page from, can you please advise? The one with B,C,D,G,F examples.
Click to expand...
Sorry - I found this once in th eweb without any original info about the source
 
Uwek said:
Really a good question

Slightly you can see the truss in you skecth with which the yardarm is pressed against the mast - to gether with (often) octagon shape of the yardarm enough friction is produced, that the yardarm is not rotating - this would be my explanation

View attachment 398972 View attachment 398975

View attachment 398973

There are a lot of different forces produced by the sails, rigging ropes etc. which are pulling and pushing a yardarm - but on a sailing ship everything also the yardarm is fixed towards the mast by friction
Click to expand...
Actually, the yardarm is not pressed against the mast as the sling passes through an opening away from the mast.
With the sling in place, the jeers are slacked slightly brining the lower yards at least a bit away from the mast.
This is important as it would be difficult to brace against the shrouds otherwise;
 
Everything needs to move (a bit) or it will break. So there is nothing to worry about, the wind shifts, the sails move, the yard moves. A little.
 
Don't forget the weight of the sail (several hundred kg in large topsails but absent in most of the illustrations given above) is effectively hanging from the bottom of the yard, which provides quite a bit of resistance to axial rotation. In later yards with iron trusses, the yard cannot rotate about its axis, only pivot side to side. In earlier yards with parrels, the fastening of the parrel as well as the halliard tie and/or jeers provide significant frictional resistance to axial rotation, often assisted by a sling cleat on the forward face of the yard.

Fred
 
fred.hocker said:
Don't forget the weight of the sail (several hundred kg in large topsails but absent in most of the illustrations given above) is effectively hanging from the bottom of the yard, which provides quite a bit of resistance to axial rotation.
Click to expand...
Absolutely! Thank you. Weight of sails must be a major contributor preventing yards to rotate.
 
Unfortunate glitch with this forum is that we do not get notifications for every new posts from the topics we are watching. This hinders the communication. As example I was never notified of very important post #11 above. I discovered it just by accident. Could moderators please bring this problem up to IT people of this forum?
 
Y.T. said:
Unfortunate glitch with this forum is that we do not get notifications for every new posts from the topics we are watching. This hinders the communication. As example I was never notified of very important post #11 above. I discovered it just by accident. Could moderators please bring this problem up to IT people of this forum?
Click to expand...
Before we initiate the call to IT people (as per your suggestion), please check your Prefrences settings (in your profile) and make sure they are in line with your expectations, specifically Persistent Alerts settings, this should work for the less active memmbers.

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Hope this this will help
 
This is great knowledge, not only about how yards are kept from rotating, but how to make sure our settings are correct to receive the email messages.
 
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