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74 Gun Ship “HMS Boomstick” From Design to Finished Model 
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JosephH 
 
Registered Member #4876 Joined: Fri Dec 23 2016, 03:37amPosts: 996  So, I got all my Diagonals in place now it is time for the rest of my reference lines.  
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JosephH 
 
Registered Member #4876 Joined: Fri Dec 23 2016, 03:37amPosts: 996  Next on our keel we need to draw a circle the radius of our Rabbet, in this case it is 2 ¼” as our Rabbet is 4 ½”.  
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JosephH 
 
Registered Member #4876 Joined: Fri Dec 23 2016, 03:37amPosts: 996  These circles we will use later to create the end point of our stations. Now we need to copy our template onto a new layer or sketch depending on software and then we want to delete everything to the left of the center line. Now, name this new sketch or layer “Fore Body Template”. We will repeat the process again but this time delete everything on the right side of the center line and name this sketch or layer “Aft Body Template”. Now make a copy of the fore body template and place it on a new sketch or layer and call it DF or Dead Flat. This will be the first station we create. Now we need to add the rising line to our station template. So, looking at our sheet it tells us that the height of our rising line for the dead flat is 11’6 inches up the center line. We also need to then draw a horizontal line from that point. We need to look at our sheet and it tells us that the half breadth of our rising line is 8’6” so from our point at 11’6” we draw a horizontal line that is 8’6” long.  
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JosephH 
 
Registered Member #4876 Joined: Fri Dec 23 2016, 03:37amPosts: 996  Now on our chart there is an asterisk next to the rising line. There is a note at the bottom of the chart that tells us that the rising line for the dead flat is 11’6” and that the rising line heights for the rest of the stations are based off that line. In other words, the dead flat rising line becomes the starting point for the dimensions given on the rest of the stations rather than the top of the keel. As you can see on the chart station B is showing a rising line height of 4” thus that becomes 11’6” + 4” = 11’10” for the height of the rising line on station B. and the rest of the stations are similar i.e. 11’6” + the rising height dimension listed for each station. So now that that is clear as mud we draw our rising line sweep for the dead flat which the end point gives us the center for one of our arcs.  
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JosephH 
 
Registered Member #4876 Joined: Fri Dec 23 2016, 03:37amPosts: 996  Next, we will draw 2 lines from the rightside line. I should mention the base line at the top of the keel is 48’ which is our moulded breadth. From the end points of that line we drew 2 vertical lines which mark the widest part of our stations. So now we will be drawing our lower and upper heights of breadth lines. We see from our chart the height of the lower height of breadth is 21’3”. We then need to look lower in the chart to the length of the lower breadth sweep which is 18’6”. After that we do the same with the upper breadth sweep and we see a height of 23’4” and a length of 15’0”. Now we want to draw the top timber line which is the top of our station, it will also give us the end point for our sweep. So, we look at the chart and it tells us the top timber line is 35’4” up our center line and the top timber half breadth is 20’8”. The last lines we need to draw are points. Each software handles these things differently. Solidworks has a “Point” drawing tool that sketches a point in space, on a line, wherever. We need to sketch a point on each of our diagonals. Then looking at our chart we want to find the length on each of the diagonal lines. For example, diagonal line 1 the length is 8’1 3/4”. Be sure you are using the lengths for the fore body as I messed up the first time and used the lengths for the after body on the fore body plan. We now have all the lines drawn we need to be able to begin drawing our station.  
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JosephH 
 
Registered Member #4876 Joined: Fri Dec 23 2016, 03:37amPosts: 996  Our first sweep is going to be the floor sweep. In order to draw this, it says to use the point on the diagonal that is closest to the head of the floor timber. Again, we need to use our charts. The floor timber won’t be listed in the bodies chart though and for that we need to look at the scantlings chart. It says the length of our floor timber amidships is 25’6”. So, we need to take half of that and draw a horizontal line high up on our centerline153” which is half of the floor timber length. Then draw a vertical line down from there to find out which point on which diagonal is the closest to that line. That point then gives us the radius of our floor sweep arc. Now personally instead of drawing arcs I prefer to draw full circles as later when we make lines tangent to it we don’t have any weird stuff happening as you sometimes get with just arcs. From the drawing of the lines it appears that the third point will be the radius of our arc.  
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JosephH 
 
Registered Member #4876 Joined: Fri Dec 23 2016, 03:37amPosts: 996  After drawing our floor sweep arc the next thing we want to do is to is to draw an arc starting from the end of our lower breadth line. We will use the length of that line as our radius.  
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JosephH 
 
Registered Member #4876 Joined: Fri Dec 23 2016, 03:37amPosts: 996  Also, after we make an arc tangent to our first two arcs, we will stop our lower breath arc even with the end of the lower breadth line. We want to draw a tangent arc of a 3point arc and make it tangent with our two circles. We also want it to intersect with the middle point of the 3 upper points so that it comes as close as possible to intersecting all 3.  
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JosephH 
 
Registered Member #4876 Joined: Fri Dec 23 2016, 03:37amPosts: 996  Now we can trim our larger circle. We will have one more arc to draw with the lower circle which we will draw next. We want another tangent arc and this time from our floor sweep circle to the little circle we drew at our rabbet, and we want it to intersect with our first diagonal point.  
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JosephH 
 
Registered Member #4876 Joined: Fri Dec 23 2016, 03:37amPosts: 996  There are just 2 lines left. The first is the upper breadth sweep which is the same as the lower in that the radius is the length of the upper breadth line. Then we draw a reconciling arc from the end of our top timber line to our upper breadth arc. Reconciling arc is just a fancy way of saying we want a tangent arc. The radius of the arc is a best guess. We do not want it too sharp nor too long, therefore we just guess.  
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