Mast placement

[Cowboy]

I am building my first model, so I'm new to this. I chose OcCre HMS Terror. Tough project for a beginner, but I am a retired cabinet and furniture maker, so I am acquainted with detail. Maybe too much

My question is are the masts supposed to be perpendicular to the deck? Mine turned out to be leaning slightly astern.

[Gregory]

Do the plans not show the angle/rake of the masts?

[James H]

34 minutes ago, Cowboy said:

I am building my first model, so I'm new to this. I chose OcCre HMS Terror. Tough project for a beginner, but I am a retired cabinet and furniture maker, so I am acquainted with detail. Maybe too much

My question is are the masts supposed to be perpendicular to the deck? Mine turned out to be leaning slightly astern.

 

I doubt that the masts would be perpendicular to the deck. Sure there should be an astern rake, even if only a few degrees.

[ccoyle]

44 minutes ago, Cowboy said:

My question is are the masts supposed to be perpendicular to the deck? Mine turned out to be leaning slightly astern.

 

Is the lean of the masts due to the arrangement of slots and holes in the hull? Does the lean match the rake shown in the plans? Will knowing there is a lean keep you awake at night?

 

That last question is the kicker.

[Cowboy]

23 minutes ago, Gregory said:

Do the plans not show the angle/rake of the masts?

It is really hard to determine. It appears that there is a slight rake on the plans. My rake may be slightly more. Hard to tell. If I am off, will it affect the  placement of the ratlines?

[Cowboy]

25 minutes ago, James H said:

 

I doubt that the masts would be perpendicular to the deck. Sure there should be an astern rake, even if only a few degrees.

o

Ok, thanks.

[Cowboy]

14 minutes ago, ccoyle said:

 

Is the lean of the masts due to the arrangement of slots and holes in the hull? Does the lean match the rake shown in the plans? Will knowing there is a lean keep you awake at night?

 

That last question is the kicker.

I won't loose any sleep over it  Perhaps theSlots dictate the rake. Thanks!

 

[Gregory]

1 hour ago, Cowboy said:

will it affect the  placement of the ratlines?

Are the masts glued in place.  If not, you can use the stays to achieve the desired rake.

To affect the run  of the ratlines in a noticeable way, the amount of rake would have to be substantial.

 

On the plans, measure the angle between the mast and the deck.  It's then fairly easy to make a template to match the angle.

Edited May 6, 2023 by Gregory

[allanyed]

22 hours ago, Cowboy said:

My question is are the masts supposed to be perpendicular to the deck? Mine turned out to be leaning slightly astern.

 Each mast is raked at different angles and there is a bit of adjustment possible on the real ship with the mast partners and wedge ring.  You can see the angles on contemporary plans and models.  There are 10 contemporary low resolution plans of Terror 1813 in the RMG Collections site. https://www.rmg.co.uk/collections/objects/rmgc-object-85464 and many of them in high resolution on the Wiki Commons site on page 17   Go to 

  https://commons.wikimedia.org/wiki/Category:Ship_plans_of_the_Royal_Museums_Greenwich  and then go to page 17.    If accuracy is of interest, study all of the drawings as they are a wealth of information.  See below for mast angles.   

Allan

Edited May 7, 2023 by allanyed

[wefalck]

Mast rake (relative to the CWL) was pretty much a fashion fob, but at least on single-masted vessels can also change the sailing performance. Up to the early decades of the 19th century masts were only slightly raked as per Allan's example above. From the 1830s on a fashion kicked in, where mast were given much more rake, particularly on ships that were supposed to be fast and had to look fast. This fashion died out again in the 1860s/1870s.

 

That said, there are many vernacular craft around the world, including Europe, that have wildly raked masts and not only backwards leaning, but also forward leaning (think of some Portuguese craft for instance). There was probably a good practical reason for this, but that may have been long forgotten, as similar craft in other regions may not have such rigs and still perform well.

[rwiederrich]

One aspect few consider is the idea that the raked masts was more detrimental to the sails life.  When raked, the sails chafed against the mast and rigging.

One particular reason why Donald McKay fashioned his namesake clipper Donald McKay with true vertical, non raked masts.  His clippers generally had .05~1.5 degree raked masts anyway.

One of the many improvements he strived to make with each clipper.

 

Rob

[wefalck]

Not sure that this statement holds in general. It depends on whether you talk about square sails or fore-and-aft as well as many other design features of the rig.

 

The main point of chafing between square sails and rig would be the shrouds. But here it depends on the parrels or cranes that would be used to support the yards and how far away they are from the mast.

 

Overall, I don't think that one or two degrees more or less in rake does have a very significant effect on chafing.

 

[rwiederrich]

4 hours ago, wefalck said:

Not sure that this statement holds in general. It depends on whether you talk about square sails or fore-and-aft as well as many other design features of the rig.

 

The main point of chafing between square sails and rig would be the shrouds. But here it depends on the parrels or cranes that would be used to support the yards and how far away they are from the mast.

 

Overall, I don't think that one or two degrees more or less in rake does have a very significant effect on chafing.

The concept may find question with the observer...and weather it holds up in general wasn't the basis of my comment. However, it was a factual determination and reasoning made by Donald McKay as to why he set all his masts vertical on his clipper ship Donald McKay.  He actively sought improvements wherever he could....I'm sure this one was not made recklessly or without evidence based reasoning.  I could be mistaken, but I thought the subject was referring to a square sailed vessel.   Sorry if I missed something.

 

Rob