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H.M.S. Ontario 
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daves 
 
Registered Member #105 Joined: Wed Jul 15 2009, 12:01pmPosts: 2624  from my research the ()'s are identical with no bevels so all the frames between (2) and (B) are deadflat.  
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dave1254 
 
Registered Member #2647 Joined: Fri May 25 2012, 08:08pmPosts: 450  I had left with instructions from the fore perpendicular measure back 34.2' and put the first section line there. Amore accurate way of placing the forward section lines is to measure from the fore perpendicular to the deadflat. take this measurement and divide by the number of spaces , not section lines to get the measurement. 34.3 / 8 = 4.2875' So draw a section line at every 4.2875' from the deadflat. To the aft section, from the deadflat measure over 2' to the center of the next section line. Mr. Coleman has a single frame here. So measure again from this section line to the aft perpendicular and then divude by the number of spaces. 44.2' / 11 = 4.018' towards the aft there is one space divided in half. Now I returned my attention to the keel . I want to outline my reasoning for what I did and see if it's sound by the others in the forum. I added the rising wood here. It's moulded dimension is calculated as 0.5 x moulded depth of the keel. In this circumstance is .565' The reason I added this now, instead of making the keel the one size of 18" , is when the ship was built, a gentlem by the name of Robert Seppings, made some changes to how the rabbit was in relation to the top of the keel. His method that was followed later was to bolt the floors directly to the keel. He made the keel larger in the moulded direction and maintained the rabbit position. As I said he made these changes at the beginning of the century and my thought was perhaps it hadn't become standard practice yet in the colonies. So I made allowance for the rising wood. I drew this line in then added the top of the floors at 1.13 ' and drew this line. Note this is measured from the top of the keel at the rabbit line. On top of the floors I drew a line 4" acroos. This represnts the limber strake and it is used later for the depth of hold. At this point I turned my attention to the aft deadwood. The construction of the deadwood is usually done with 8 pieces. One of them is the deadwood knee that supports at the top of the deadwood the sterpost and the transoms. Where the deadwood starts to rise to the tramsoms is where the rising wood is scarphed into the first 2 pieces of wood. At the sterpost the first piece is moulded the thickness of the keel and tapers to the rising wood that is cut 3" vertical then tapers to the top of the rising wood . the next piece is again the moulded of the keel sitting on top of the first piece then cut to the scarph at the rising , there by locking it in place. The next piece is scarphed into the lower by lowering it 4" and then tapering back by the standard 3x the moulded depth. I know the front piece has a point but my thinking is if the carpenters put a square scantling on and then cut in the curve before putting on the stemson this might be appropriate. I continued this method up arriving at the knee. I added the front piece that locks it all in and then cut to the curve , known as the cut down line. I then added the transoms. Here there are 4 , the deck transom and 3 fillers. I determined the size of the wing transom which is, by definition, width as 1" for every 1' of length, it's depth is 5/12 of the width, and length as 2/3 of moulded breadth. All other transoms are 7/8th of these measurements. The deck transom situated at the deck is 7/8ths of the wing transom measurements and also " lapped under ends of lower deck planking 3 1/2" in length and 3" deep " I take this to mean rabbitted in at the planking side. There is also a space between each transom for air. Usually 3 to 4" in size. So therefore the wing transom L= 16.3' , W= 16.3" D = 6.79" The other transoms are 7/8th of these measurements. I drew in the deck transom #" above the floor measurement and then drew in the depth added 3" for air and the 3 other transoms. Until I determine the shape of the Fashion piece I can't draw this in yet. OK I failed to mention how I got the lower deck heights. From the top of the Limber strake measure up 9'. This is the depth of hold. It measures from the top of the Limber strake to the top of the beams of the lower deck. This vdoes not include the deck planking. Draw this line across to the stem and sternpost. The fore and aft shear is added to this. They are: Aft shear =1/5th depth of hold = 1.8' the fore sheer is 2 1/4" for every 10' of length = 1.5' I add this to the depth of hold measurement respectfully and make a mark. Next because there are deadflats or either side of the main deadflat, you wil notice ( ) 's around these letters and numbers it means these frames are the same. So I drew a straight line at the 9' measurement acroos these deadflats. Then I drew a curve from the aft mark of the sheer rise at sternpost to the first deadflat and another curve from the fore sheer rise mark to the front deadflat. This is the shape of the lower ( gun) deck. I added the scarphs to the stem and apron at the standard sizes (3x moulded ) amd blending in the dead rise wood to the apron via scarph as well. I'll explain the red lines next.  
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dave1254 
 
Registered Member #2647 Joined: Fri May 25 2012, 08:08pmPosts: 450  Sorry it sounds like a teacher. I guess when you've done it for so long it's in your blood.  
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dave1254 
 
Registered Member #2647 Joined: Fri May 25 2012, 08:08pmPosts: 450  I wish to clarify some things here. As I said I am not an expert on this and I am making mistakes. It must be remembered that I am not familiar with the math formulas like the experts of the day. One formula that I use I may find it' gets me moving in the right direction but produces an error later. Also I am reluctant to use a formula with an item that I am unfamiliar with. e.g. the sternpost length. I had to change the length again because it didn't add up to where it should fit. I have had this new formula for awhile but the one part I was unfamiliar with, so I only used till recently. It involves the Trim. The experts back then knew these formulas because they worked with them all the time. If you are going to use what I am doing; to use on other drawings then I advise you to read the whole thing and look for the changes. I will throughout this exercise tell you so that you are familiar with it and the changes needed. Thanks for letting me do this and your advice is trully appreciated because it's helping me learn along the way. BTW: Overlaying the original draughts onto what I am doing, I am finding it matching. There are some varients but that is in areas where there is no fixed math involved. When Deanne says to " screw up your bow and draw an arc " this leaves open for error. Don't let the math involved bother you. It is stuff we learned in elementary school, it just seemes complicated. It was very advanced math to them and possibly a very select few could do. If you are like my students of old and as soon as I said math the eyes glazed over and I already lost some. Dave1254  
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dave1254 
 
Registered Member #2647 Joined: Fri May 25 2012, 08:08pmPosts: 450  The next step that is needed are the counters at the stern. Deanne states from the intersection of the top of the transom and the rabbit measure across 4'. The lower counter for this time period was usually set at 30 degrees from this point. At the 4' mark draw a perpendicular to the 30 degree line. Draw 2 arcs from the end points 7' radius. Now draw the arc at the intersections. Add 6" for the width of the timbers and redraw another arc. The top counter is drawn similar to the lower. Measure over and draw a line 1/4 of lower counter. 1/4 of 4' = 1' Draw a perpendicular at this point. The angle usually at this time period was set at 60 degrees. Draw a line from the lower counter end to the perpendicular at the 1' mark. Again o draw 7' arcs from each corner and then draw the arc for the upper counter. Add 6" again for the width of the counter and redraw the arc. The stern face of the master cabin was set on an angle anywhere from 70 to 85 degrees. I set the angle to 70 degrees because the sterpost is at 80 degrees and it appears to be less of an angle than that on the draughts. Not scientific but does fit. I drew a line from the end of the upper counter to a 70 degree angle. I then offset the line in cad 6" and drew a secound line inside the first one. I trimmed everything and all I have to do now are the upper deck . The upper deck or the top limber line is determined by taking 1/5th of the lower deck length. 1/5 x 80’ = 16’ I measured and drew in the 18’ line at the deadflats and then using the deck below for the sheer rise I offset the required amout and copied the fore and aft deck . I then extended the lines to the front stem and to the aft . The lines above this that don’t extend all the way across are the highest point the frames extend to. This done by taking 1/10th of the moulded breadth. 1/10th x 24.5 = 2.45’ The 2 red lines: These 2 lines represent the rising line of the upper height of breadth and the lower line represents the rising line of lower height of breadth. At the stern it is first located at the intersection on the lower deck and the rabbit . At the stem it is located at the height determined by taking ¾ of the height of the sternpost ¾ of 19.07 = 14.30’ Start at the stern and draw an arc from that point to the first deadflat. Then draw another arc from the forward deadflat to the 14.30’ mark on the stem at the inside of the uprights. You will notice they start off following the lower deck but rise past as it nears the stem. Next draw in the lower height of breadth. First off I needed to determine where on the deadflats it was located. By definition it is the same as the lower wale at midships. Since I haven’t done those yet I determined that the lowest wale was 6” below the water line. I temporarily drew in the wale measured it and marked in on the drawing. I erased the wale because it complicates what I am trying to see right now. I will add later. So I drew across the deadflats at this mark and then starting again at the stern I drew an arc from there to the lower breadth mark and then to the stem mark. These lines are very important in the next few steps.  
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dave1254 
 
Registered Member #2647 Joined: Fri May 25 2012, 08:08pmPosts: 450  The Rising line of Floors To determine this I went to Mr. Deanne, He states to draw a perpendicular from the waterline mark that intersects at the stern post. Then measure this height. Then measure from this intersection along the base of the keel to the first deadflat. This measures 40.2' The height of the perpendicular measures 10.11' Now Deanne says to double the base dimension 40.2x 40.2 = 1616.04' now divide by the perpendicular height 1616/ 10.11 = 159.85' Now add the perpendicular 159.85' + 10.11' = 169.96 Now divide by 2 169.96 / 2 = 84.98' This represents the true center of the radius for the aft rise of line. So at the waterline intersection draw an arc 83.98' and from the base of the keel at the center deadflat not at the 40.2' mark. The reasoning here is because Deanne goes from the calculated deadflat of the ship not by the first deadflat like on the Ontario. Now draw the arc from the intersection to the first deadflat ( not the calculated one ) at the section line and the dead rise ( 5.65 "). I trimmed all unwanted lines at this point. You will notice at the waterline and sternpost it is slightly above. According to the draughts this where it should be. The forward rise of line is done similar. Draw a perpendicular from the waterline intersection and the frony stem down to thw lower part of the keel. Now measure this Measure from the calculated deadflat position to the perpendicular you just drew. Following Deannes description again , I doubled the base measurement 35.43x 35.43 = 1255.29' Then taking this number and divide by the perpendicular number 1255.29 / 9.36' =134.11' Now I add the number 134.11 + 9.36' = 143.47' Then I divide by 2 143.47' / 2 = 71.74' I drew 2 arcs one from the dead rise on the calculated deadflat and the other at the intersection of the waterline and the aft rabbit line 71.74' for each. At this intersection of the 2 arcs I drew the arc from the intersection of the forward deadflat of the calculated deadflat and the dead rise to the beginning of the rabbit on the stem. This is the forward rise of the floors. I checked the draught and the position of the line seems to match. If there was 1 daedflat in the ship then these measurements would be a lot simplier. [ Edited Tue Jun 19 2012, 07:27pm ]  
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dave1254 
 
Registered Member #2647 Joined: Fri May 25 2012, 08:08pmPosts: 450  The Hakf Breadth Plan I drew a line below the keel and parallel to it . I then measured up 12.125' ( 1/2 of the moulded breadth) and drew another line parallel to the first one. Next I extended the section lines and the 2 perpendiculars down to the very first line I drew. Everything I do next will fit into this rectangle. Oh Yes If you haven't done so drop a perpendicular from the intersection of the upper deck and the upper cabin frame to the first line as well. I start with the forward curve. At the deadflat next to the calculated one draw an arc from the top of the perpendicular towards the fore of the ship down to the first line we drew. ( I will call this the base line). Measure the distance of this arc along the base line 12.25'. ( refer to the drawing that I provide here) Now divide this length by7, this gives you 6 perpendiculars. Draw perpendiculars from each size ( 1.75') to the arc you created. Now I drew lines parallel to the base line from these points to the perpendiculars they correspond to. As an example the point of intersection at the very top of the arc goes to the section line next to the deadflat etc. When that was done I created an arc by just connecting the ends. The last part of the arc connects to the inside of the rabbit. The back half is done similar to the front. But first I had to find the length of the transom that fits there and also draw in its curve. According to the definition the wing transom length is 2/3 the extreme breadth for all 1st and 2nd rates and all the rest 1 foot less. 2/3 x 25  1’ = 15.67’ for half breadth plan /2 = 7.84’ The curve of the transom is described as “ determined by the distance between the fore edge of sternpost and the after edge of the fashion piece” For the actual size of the wing transom, another definition is: “ for thickness, breadth and the curve take as many 1” as the wing transom is broad in 1’” and another “ the wing transom is sided and moulded the same as the floor timbers” a lot to make sense of and a lot to choose from. The floor timbers are 1.13’ x 10.2 “ so I made the wing transom 1.3’ x .85’ with a curve of 1.3’ I again assume there is no set rule that says a transom has to be exactly this size but it is really determined by the cant of the fashion piece. From the intersection of the calculated deadflat I drew an arc from the sternpost to the 7.84’ line and this is the shape of the wing transom. Once I determined the length, at the perpendicular in the half breadth plan for the intersection of the sternpost and transom I measured up 7.84’ and drew a line parallel to the base line to the arc. Then I made a perpendicular from this intersection down to the base line. Following what I did before I ended up with the curve to the back of the transom. The next step is the top breadth line .  
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dave1254 
 
Registered Member #2647 Joined: Fri May 25 2012, 08:08pmPosts: 450  To do the next line I have to determine the Tunblehome of the ship. It is defined as 2" for every foot of length. 2" x 80 = 40" and because I am doing the half breadth plan I divided by 2 40" / 2 = 20" or 1.67'. At the aft perpendicular of the wing transom I just finished ( the red line) I measured towards the base line 1.67' and drew a line to the perpenicular at the aft of the breadth plan. Then using the same point of radius, from the center of the calculated deadflat, I drew the curve from the bottom base line to the line of the tumblehome. Like the previous example I drew an arc at the deadflat , drew the line from the tumblehome intersection to the arc, then a perpendicular from that point to the base line. I measured the distance and divided by the number of spaces and then drew perpendiculars from every distance to the arc, then parallel lines from every end point to their corresponding section line, then connected the ends to form the curve. I repeated the steps for the front half. This is what it looks like finished. I hope your not confused. It really is quite simple.  
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dave1254 
 
Registered Member #2647 Joined: Fri May 25 2012, 08:08pmPosts: 450  The Body Plan If your like me, when I look at the body plan to begin tracing the individual frames I get confused at the amount of compactness around the Dead flat area. I found now that you can redraw individual frames simply and you don’t need cad to do it. Very simple math and the ship’s breadth allow you to redraw them. I transferred all the lines from the Sheer draught that I need. I gave myself lots of room between the Sheer and the Body plan. Next I drew 3 perpendiculars. One center line and a perpendicular on either side spaced 12.25’ apart. Next at the center line I drew perpendiculars, one on either side of the center line .52'. This represents the keel. At the base of the keel I measured up 1.13' and drew a line, this represents the top of the keel. I put in the 3” rabbet at this time on either side. Above the keel I measured up .68' and drew another line, this represents the dead rise. You can add the false keel if you like. Starting at station (2) this is a Dead flat frame. From the sheer plan I made sure I transferred across the upper and lower maximum breadth lines, and the sheer line. BTW, I drew the numbered frames on the left hand side of the Body plan. Now I measured on the half breadth plan the distance from the center line to the arc of the rising line at station (2). I transferred this from the center of the keel out, parallel to the base line. I created a perpendicular here. Then I measured the distance between the two Breadth lines at station (2). This was 2.3’ and transferred this dimension to top of the perpendicular at the sheer line. Deanne does the upper sweeps of his body plan without the upper max. breadth line included. I used his method to determine the center of the upper sweep at the upper breadth line. Ok so this is what you should have on the drawing. Step 1: To determine the floor sweep take ¼ of the ships breadth. In this case ¼ of 24.5’ = 6.125’. At the rise of the floors perpendicular I measured up 6.125’ from the dead rise and drew the floor sweep. Step 2: Next I took 7/9’s of the floor sweep 7/9 x 6.125 = 4.76’. At the lower breadth line at the far perpendicular I measured in 4.76’ and drew in the lower sweep. Step 3: Next I took 20/36th’s of the breadth of the ship 20/36 x 24.5’ = 13.61’. This determines the reconciling sweep. At the intersection of the lower breadth line and far perpendicular, I drew an arc near the center line of the ship. Taking the same measurement and at the intersection of the base line and the rise of floors perpendicular I drew another arc that intersected the first arc. From here I drew the arc 13.61’ that blended the 2 previous arcs. This is what I have so far. This next step is where Deanne does not include the upper breadth line to do the sweeps. What I did was use his method and where it intersected the upper breadth line made the sweeps. I took 17/18th’s of the half breadth 17/18 x 12.25 = 11.57’. At the lower breadth line I measured over from the outer perpendicular 11.57’ and made an arc here. From this intersection I drew another arc towards the left of the tumblehome area, 23.14’. I doubled the value. Next, from the intersection of the sheer line and the tumblehome mark I drew another arc with a radius of 11.57’ till it intersected the first arc. I drew a line between this intersection and the intersection of the lower breadth line and the 17/18th’s mark. This is what I have. Now I have the intersection at the upper breadth line that I can work from to get the upper sweeps. I created the upper sweep at the intersection of the upper breadth line and the diagonal I created before. Now I measured the arc at the diagonal of 7.08’. Again I doubled this measurement and then drew another arc towards the tumblehome area. Next I took the measurement of 7.08’ and made an arc from the tumblehome to that arc. At this intersection I drew a line connecting the 2 intersections like before. Now I created an arc from this intersection to the upper sweep. I trimmed everything and there is the section (2). The only thing left to do is the line from the top of the rabbet to the intersection of the floor sweep and dead rise. There is a very tiny sweep to this area. What has to happen is I had to draw off the tangent of the lower floor sweep to the rabbet. When you use cad you can set up osnap to register tangents of curves. When I did this the point is off from the intersection. When I do the other sections this became more prevalent as the radius for the lower floor sweep to the rabbet becomes bigger. For this frame I left it as a straight line from the tangent. If you use paper and pencil if you put your straight edge from the rabbet to the floor sweep this will automatically find the spot. I will do another section with a more pronounced curve to show the math involved. [ Edited Sun Jul 08 2012, 02:00pm ]  
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dave1254 
 
Registered Member #2647 Joined: Fri May 25 2012, 08:08pmPosts: 450  To do section # 11 As before I transferred acroos from the sheer draught and the half breadth plan all relevant information. This is what I have. section 11 I took 1/4 of the breadth 1/4 x 21.78 = 5.45' I created the floor sweep at this point. Next I took 7/9th's of the floor sweep 7/0 x 5.45 = 4.24' I created the lower breadth sweep. Next I created the reconciling arc 20/36 x 21.78 = 12.1' You will notice it doesn't touch the floor sweep. Don't worry. Next I created the upper sweeps. I took 17/18th's of the half breadth 17/18 x 10.89 = 10.29'. I measured over from the perpendicular at the lower breadth and made an arc . Then I doubled the figure and created an arc towards the upper left of the tumblehome. 20.58' Then I measured over from the tumblehome and created an arc 10.29' I then joined the 2 intersections with a line. This created the intersection at the upper breadth line. From this intersection I created the upper breadth sweep. I then measured this distance . 7.37' Again I doubled this and created an arc to the left of the tumblehome at 14.74'. At the tumble home I created another arc to the left again at 7.37'. I connected the 2 intersections with a line. At the top intersection I created an arc that touched the upper sweep. I trimmed everything. The upper section is done now for the lower sweeps. LIke the previous examples or methods, The reconciling sweep measurement I doubled and created an arc towards the lower left of the section. 25.82'. At the top of the keel at the rabbet I created another arc in the same direction of 12.91'. At the 2 intersections I connected with a line. I then created an arc from the lower intersection to the reconciling arc. I then trimmed everything. Section 11 is complete. I will finish off the remaining body plan sections and then work on the water lines.  
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