Soleil Royal by EricWiberg - Heller - 1/100 - PLASTIC - started 45 years ago

[EricWiberg]

OK, I have to admit I am puzzled by calculating the distance between gun ports.

 

From the several build logs that I have read... lets assume there are 10 gun ports that are 10mm wide, and the "ship length" is 210mm in length. 210mm - (10 x 10mm) = 110mm. Because there are 10 gun ports. there are 11 spaces, so 210mm / 11 = 10mm.... so I have ten gun ports that are 10mm wide and spaced 10mm apart.

 

But should we not use the length on the outside of the hull, as opposed to the "ship length"? In the photo below, I used the lower gun deck as the "ship length" in this example, as it is very easy to see. The lower gun deck is 543mm in length... so with 16 gun ports that are 8.7mm wide... 543 - (16*8.7mm) = 403.8mm... (403.8mm) / 17 = 23.7mm between gun ports.

 

BUT... if I put a tape measure on the outside of the hull at the Lower Gun Deck level, I get 571mm in length as the hull curve is longer than the deck.... so 571 - (16*8.7mm) = 431.8mm... (431.8) / 17 = 25.4mm between gun ports.

 

This is a substantial difference and really adds up with 16 gun ports... what am I missing here?

 

In practice, I will mark the positions of gun ports #2 and #16, and calculate the spacing between them (the #1 gun port, or chase port, can't be used as a starting point as it is positioned 1.5x the normal spacing ahead of gun port #2). Even using the distance from #2 to #16, the measuring tape wrapped  around the hull is longer than the deck length by over 3/4" of an inch. It doesn't sound like much, but the spacing gaps will become very noticeable to the eye.

 

[Hubac's Historian]

I think you measure along the outside of the hull.  As you say, establish the position of port #’s 2 and 16, and then calculate even spacing for the guns in-between.  A straight linear measurement of the deck length is not particularly useful, here.

 

Here is a poor drawing illustrating the calculation.  Port numbering not so important, here.  You get the idea:

[Hubac's Historian]

At scale, if you end up in the vicinity of 6.5 - 7’ between ports, then that’s where you want to be.