Proportion of Spars

[Bill Jackson]

Hi guys,

I have read, and read, and read somemore, but I keep getting different answers from each book. One book tells me the lower main spar should be 90% of the main mask length. Another book tells me it should be 80% of the main mast. Still another book tells me it should be 7/8th of the main mast, and finally one book says "if the main spar is more than double the ships beam its too long".

Shall I jump off the bridge now or is there a correct answer. I am building a ship from the 15th century, a Carrack.

Bill

[Dr PR]

Bill,

 

This is par for the course. There are as many answers as there are people. And that is the way it would have been in the 1400s.

 

Unless you have actual plans for the vessel you are building you should just pick whatever looks good. 80% to 90% but not more than twice the beam.

[Bill Jackson]

38 minutes ago, Dr PR said:

Bill,

 

This is par for the course. There are as many answers as there are people. And that is the way it would have been in the 1400s.

 

Unless you have actual plans for the vessel you are building you should just pick whatever looks good. 80% to 90% but not more than twice the beam.

Doc the 80 or 90 percent of the length of the main mast, either one, is more than twice the beam of th3 ship. Over....?

[Jaager]

In which case, go with the max allowed:  twice the beam.

[allanyed]

The determination of the lengths varied with the era.  What ship/nation/year are you interested in?  Lees' information was developed from contemporary masting tables and from proportionate tables given in contemporary books and manuscripts. If you use Danny Vadas' spread sheets in the Articles Database here at MSW which are based on David Lee's formulas in The Masting and Rigging of English Ships of War (except do not use for ships built between 1670 and 1710 as the formula he made up is wrong) you should be close.  There are contemporary drawings of the masts and yards available at the RMG Collections site and on the Wiki Commons website for specific ships but i have no idea if they are appropriate without knowing which vessel you have in mind.

 

The era is very important as the lengths of the yards were sometime a proportion of the length of the mast, sometimes, the length of the keel, and others as a proportion of the length of the gundeck.

 

If  you are referring to the 1492 carrack (Santa Maria??) that you mentioned in previous posts, consider using Lees earliest era formula

 

Length of main yard is 5/6 the length of the keel.  

0.833X41=34.17 feet   

This is close to the double the beam length which would give you main yard of 36 feet long.

The foreyard would be 0.80 the length of the main yard.

The lengths of the upper yards are all a proportion of the lower yards. 

Allan

Edited February 19, 2023 by allanyed