Are Gunports square? - modifed by mod

[GARY B]

Morning all

Are gunports square. I know the sides run parellal to the frames. Its the cills and head I am having trouble getting my head round. The diff is fractions off a mm fore and aft. Hope that makes sense as i dont want to build them wrong.

Garyb

[Doreltomin]

Hello Gary, the answer to your question is, as always "depends"

 

Depends on epoch and more important, depends on nationality.

 

One thing is certain, the gunports were cut after the deck beams were placed in place and the deck was laid, so that the lower and upper sill were always put parallel to the deck. Now there is a wide debate even among the members of this forum whether the other two sides are put square to the upper and lower or were put parallel to the frames. Some say the first, some say the second. In the first case the lids would be rectangles with square corners, in the next they would be slightly parallelograms in shape. One thing is certain: square (which is, with the height equal to the width) they never were. 

 

Tell us which nationality and which epoch your ship is, then we may come out with a more detailed answer!

[Chuck]

The port sill and lintel usually follow the run of the deck.   Therefore they are usually not square square.  While the uprights are perfectly vertical.

[Chuck]

There are always exceptions.  But if you stick with the usual for 99% of the ships out there you will be in good shape.   

[GARY B]

Thank you chaps for confirming what I thought . Iam on the right track  always amazed how you are willing to share and help.

Garyb

[dafi]

Depends very much upon the epoch as said before. 

 

Later ships have the paralellogram shape with vertical frames and horizontally following the lines of the deck - which makes sense for the height of the gun barrels.

 

Earlier ships like Vasa have much more squared ports, as the frames were build after the shell and the ports apparently seem to be simply "cut out".

http://wasadream.com/Index/indexenglish.html   picture 35

 

XXXDAn

 

PS: Also with the model of the Prince in London I am not sure, that the ports are not not square.

Edited December 21, 2015 by dafi

[Mark P]

Hi Gary;

 

You may well already be aware of this,  but certainly in the Royal Navy gunports were a set size for a particular poundage of gun.  Contracts also stipulated the height of the gunport cill above the deck,  and the number and size of eye bolts and ring bolts to be used on each deck.

 

All the best,

 

Mark Po

[jbshan]

Anthony Deane begins with the number and size of the guns on the gun deck.  That determines, with the size of the port openings and their spacing, plus some length added fore and aft, the length of the ship.  The number of guns determines the scantlings of the frame members and their spacing, and so on and so on.

[georgeband]

It is very reassuring for me to see the Haddock drawing above from daves. 

I have been looking at this drawing for a long while and the varying sizes and shapes of the gunports did not look right, but I have to trust the shipwright who measured the schooner and drew the lines. Equally interesting is how the original build in Bermuda was altered by the people at Portsmouth - the fine dotted lines show the changes. 

 

George