HMS Bellona 1760 by SJSoane - Scale 1:64 - English 74-gun - as designed

[EdT]

Mark,

 

The dashed line and its intersection with the decks makes no sense to me.  I can offer no suggestion apart from poor draftsmanship.  This is an inboard works drawing and not a disposition of frame, which might be more accurate on this detail.  I suggest you look at the half breadth plan and plot the intersections of longitudinal lines on the stem to determine the location of the rabbet.  this may offer a clue to the lines in the elevation drawing.

 

Ed

[Siggi52]

Hello Mark,

 

I looked at the plan, in color and it is really in color there. Wait until you get plan from me. That plan was used for 27 or more ships! 

 

Greetings,

Siggi

[Siggi52]

Why shod you wait, I made a screen shot of the plan. It's late here ;-)

 

Siggi

[SJSoane]

Ah hah! Ed, thanks for pointing me to the plans. The distance in the sheer from the forward perpendicular to the dotted line at the level of the gun deck is exactly the same as the distance in the gun deck plan, to the aft side of the frames (see below). And the rabbet is therefore forward of the fore perpendicular by the thickness of the frames.

 

The dotted line shows up in both the inboard works and the sheer drawing, and is consistent with the plans, so I am assuming now that this was not a mistake.

 

I am assuming from the responses from Ed and druxey that this is not normal drafting for these ships... Ah, the Bellona, I love her even more the quirkier she becomes...

 

Mark

 

[SJSoane]

 

Hi Siggi,

 

Your drawing confirms it! The dotted line represents the aft face of the frame timbers at the bow, and the rabbet obviously shows the fore face of the frames.

 

Thanks, everyone.

 

Mark

[druxey]

I'm not happy with the explanation, gentlemen. If the difference between the dashed line and inner rabbet line is the thickness of the frame - or bollard timber - one would expect the distance between those lines to increase the further down one goes, not have it taper out to nothing. This need further examination.

[Alex M]

Hi Mark,

 

such inboard profiles are usually as designed, copies are sended to ship yards and used for all ships of the design. It can be, that the dashed line represents just a difference between design and particular ship as build, or it is later plan with alterations for further ships, or some else, but not aft face or thickness of frames. In this case the line should run more or less parallel to rabbet. With other words, as I assume, the dashed line show the true rabbet of Bellona, because the line match the fore perpendicular. And the plan show probably later ships slightly largened

 

Alex

[CTDavies]

I have a question here about the NMM's Bellona plans that I imported into my CAD programme for an off and on project. On the side elevation I noticed the frames stations are tilted very slightly to the rear. I have the elevation placed in my CAD programme with the water lines absolutely horizontal, which makes sense to me. The scale bar under the keel rises towards the bow which also looks right. So I was wondering if the rear tilted frames might be due to the photographic process in the museum or even scanning them here afterwards (or a combination of both).

This is an amazing thread and one of my favorites on MSW. I come back here frequently to see Marks progress and follow the discussions.

Chris

[druxey]

Alex: that's exactly the reason I asked whether the plan was an 'as built' one or not.

[EdT]

I agree with Druxey that this does not look like the inside of frame for the reason he cites.

 

After looking at the drawing again, I sggest that this line is the joint between he stem and the apron that backs the stem. It appears to be parallel to the forward face of he stem over its length. I suggest measuring the distance between the dashed line and the forward line of the stem and check it against the scantling for the molded breadth of the stem (I believe 18"). You could also check the distance from the ashed line back the the solid line against the scantling for the apron (I beleive 11"). It would make sense to show this line dashed as a reference since the length on the gun deck - a primary measure - would be from the aft side of the stem - not the apron - to the sternpost.

 

 

Ed

[SJSoane]

 

Hi druxey,

 

Siggi and I have different versions of the Bellona sheer; with different notes in the margins. Both show the same dotted line in the stem. Mine contains two notes about alterations. The one I can read is over the quarterdeck, and says:

 

"Bulkhead ticked [or licked] in, are as was altered by the Surveyor directions, went to Deptford and Chatham with the alterations in the Upper and Quarterdeck [plan?] as in red."

 

The other note is further aft, behind the mizen mast, but it is too faint for me to read most of it. The last part says "...Upper and [?] as in red..." There are dotted lines showing different locations of the bulkheads in the captain's cabin, and the gun ports on the quarterdeck and the aft end of the upper deck are picked out in three different locations. I assume this note refers to these details in the after works. 

 

So it is showing alterations, presumably before or during construction, with the note about being sent to the dockyards. But there are no notes at the stem referring to the dotted line mystery.

 

Siggi's colored sheer drawing posted above shows extensive notes at the stem. Siggi, are you able to read those notes? And if so, do they say anything about the stem dotted line? 

 

I am going to look more carefully at the gun deck and upper deck plans this morning, to see if they correspond in any way to the dotted line.

 

I love the detective work!

 

Mark

[SJSoane]

Ed, I just saw your note while I was typing mine. I'll also look at the scantlings for the apron and stem while I am sleuthing.

 

Mark

 

[garyshipwright]

Hope no one mind a stranger joining in but do agree with Ed, it does look like the joint line between the apron and stem.

Gary

[SJSoane]

 

HI Gary,

 

Great to hear from you!

 

Yes, I am starting to think this is the joint between apron and stem. I am going to draw a little more this morning and see if this becomes clearer.

 

Best wishes,

 

Mark

[Siggi52]

Mark, that was the plan for the inboard profile I posted. I posted that plan, because the plan you posted looked similar. The first picture I send now will explain fore witch ships that plan was used also. The second picture are the writings at this plan. Sorry I could't read it.

 

The third picture is the from the sheer plan. That is the plan for only the Dragon and no other ship. May be that plan is better for your research. 

 

Regards,

Siggi

 

 

[Siggi52]

I forget to mention that the two plans do not match each other. What I learned the hard way was, that as an example the decks have a different high! So may be there are other differences.

 

Siggi

[wq3296]

Greetings Mark,

 

I checked Chapelle"s book, the American Sailing Navy. Plan 20 shows 74 gun ship Ohio. The rabbit line is shown exactly how would expect it to be (i.e. uniform all the way to the top of the stem.) Other scale drawings in the book for other ships show the same thing. It may be that the dotted line you mention is not the rabbit line at all. I think the rabbit line is represented by the solid line just forward of the dotted line. Note that at the forefoot, and for most of the way up, you have solid lines that seem to then become dotted. The other dotted line that you think is the rabbit veers aft. This leads me to believe that that dotted line represents the termination of deck framing or something else as has been suggested. It may not be faulty drafting at all. Without additional drawings, notes, or call outs,it's true purpose is indeterminate. What difference does it make anyway? You know as a model builder how the rabbit should be shown, so change your drawings accordingly. 

 

wq3296

[druxey]

I agree with Gary's assessment. Look at the rabbet as shown on the deck plan. It appears within the width of the stem, rather than at its aft edge. What is unusual is that the stem/apron joint line is shown as a dashed one on the sheer and profile. Usually joint lines are delineated as solid lines on these draughts. I think that is what threw us. I suppose it was the draftsman's way of demonstrating that the rabbet progressively moved forward of this joint as it moved up the stem.

[SJSoane]

 

I spent a day drawing more, and I am now quite sure at this point that Ed, druxey, and Gary figured this out. The dotted line represents the joint between the apron and the stem, and the rabbet starts in this joint lower down, but begins to veer forward into the stem itself starting a little below the gun deck.

 

Siggi, I'll have a go at reading the notes on your drawing when I see it. I will be very interested in comparing the two versions of our plans.

 

What an amazing  team of experts on this website. Thanks so much!

 

Mark

[druxey]

Glad we solved that mystery. I can sleep tonight now!

[SJSoane]

 

Hi everyone,

 

I am slowly working up some CAD drawings of the Bellona, to consolidate all of the changes I made over the years to the original hand drafted drawings. I thought some of the more obsessive of us out there might enjoy seeing how I finally figured out the geometry of the scrolls or volutes at the fore edge of the quarterdeck.

 

My architecture background came in handy, because I believe the geometry in the Bellona's volute is the same construction as that used to make an Ionic volute capital in Classical architecture. I hope the enlarged geometry is self explanatory, but just in case, a square on a 45 degree angle is inscribed within a circle. The mid points of each side of the square are projected out as shown. The compass point is first placed on upper end of the 6 o-clock line, and the pencil end goes down to the end of that line. A compass arc is then drawn to the 9 o'clock position, and the compass point is then placed in inner end of the 9 o'clock line. A compass arc is then drawn to the 12 o'clock position, and so on.

 

You will notice that the square inscribed within the circle is not the same diameter as the final central circle that shows in the volute. It took me a long time to realize that these did not have to be the same size, and indeed cannot be if the scroll is to take its final shape. I had to experiment with how big the construction circle needed to be, to make the volute fit in its proscribed space. Finally, the circle at the fore edge of this construction does not have the same center as the volute; its center can be seen at the lower end of the vertical line which intersects the topmost line to the upper left, and the beginning of the outer circle.

 

Many wasted--I mean happy--hours were spent figuring out where the centers are for all of these constructions, to match the appearance of the scrolls in the Admiralty drawings.

 

At this point, is anyone wondering if I am procrastinating about starting working on the model itself again?

 

Best wishes,

 

Mark

 

 

 

 

[dvm27]

The hance work, with their volute scrolls, always captures my attention on my visits to the Naval Academy Museum in Annapolis. Your illustration is brilliant. Have fun turning it into reality!

 

Photo from one of my favorite models Royal George, 1715.

 

[michael mott]

Mark those scrolls will be exquisite. Nice drawing, and thanks for the kind words in Skipjack.

 

Michael.

[druxey]

Nicely adapted from Ionic capital geometric construction, Mark. Now let's see it translated into 3D reality!

[EdT]

Sounds like you are being challenged, Mark.  Sharpen up those gouges.

 

Very interesting geometry, by the way.

 

Ed

[wrkempson]

Well, there's a couple of hours I won't get back; but worth it.  It took me a while to realize the two eastern quadrants of the outside curve comprise a semi circle and that for the outside curve the spiral begins at the bottom.  The inner spiral begins at the top.  How to locate the center of the semi circle took a minute as did the proper way to construct and locate the inner square. I began by looking up how to draw the volute of an Ionic capital (which led me down some false paths) but did get a start on how to back engineer your drawing. Thanks for the challenge.  I have no experience with architectural drawings like this, so it was a couple of hours of pure learning.  Not bad. 

 

My end product looked (to my eye) the same as yours, so no sense posting it.  Nonetheless, I guess I qualify as one of the more obsessive among us!

 

Wayne

[Trussben]

Hi Mark,

 

I'm glad I stopped by and caught up on your log, I have been working on my Indy plans and wondered what the dotted line abaft the rabbit was meaning, now I know!!

 

Great work.

 

Ben

[SJSoane]

 

Hi everyone,

 

I have been away, and just got back to the website. Greg, Michael, druxey and Ed, I hoped I wouldn't actually have to build it, once I drew it....;-)

 

All kidding aside, it is interesting how precise one has to be with CAD, or it doesn't get drawn at all. When I first drew it freehand in my original hand drafted drawings, I now realize I was able to fudge exactly where things began and ended, and I am sure my curves were not sections of accurate circles. Freehand has its virtues. And yet, when it is actually built at my small scale of 1:64, the subtleties of where exactly the scroll begins hardly matter. It is a lesson in understanding appropriate tolerances at different scales.

 

Wayne, I hope I didn't lead you down a rabbit-hole with this exercise. But it sounds like you learned as much as I did about interesting geometrical constructions from the 18th century and before (the volute in Classical architecture goes back to 500 BC or earlier). It is very satisfying to puzzle through a geometrical construction, and then when you draw for the final time, everything just falls into place. Obsession has its rewards!

 

This construction is also a reminder for me that our predecessors relied much more on relative proportions and geometrical constructions for forming complex shapes including an entire ship design. We don't tend to think as much today of objects in terms of their proportional relations to other objects when designing and drawing. Perhaps we lost some important ways of looking at the world.

 

And Ben, I am glad solving my puzzle helped solve yours regarding the dotted lines in the stem construction. Further evidence of why this website is so valuable to us all.

 

Best wishes,

 

Mark

[gjdale]

Mark,

 

I think you're little sojourn into Classical architecture and geometric construction was a fascinating trip for all of us. Thank you for sharing this.

[SJSoane]

 

Hi everyone,

 

A long time away from the shipyard. I last got the deck clamps in before the winter humidity in Colorado drops dramatically, and I will have to wait until spring to start on the main wales when the humidity comes back to match what it was when the clamps went in. So, I am backing and filling for a while....

 

I learned about sail making from Greg Herbert and David Antscherl's workshop this December, and may post some pictures of my sail efforts for the Bellona at some point when I have something to show. It was a terrific workshop. I highly recommend it.

 

In the meantime, I am working on the 32# guns for the Bellona's gundeck. I spent a fair amount of time researching guns that would be appropriate to ca. 1760. I may have this wrong, but I believe the guns at this time were based on a pattern developed by Surveyor General of Ordnance, General John Armstrong, in the 1720s. This was updated slightly by Charles Frederick in 1753. And the dimensions were given in John Muller's Treatise on Ordnance of 1768. Using Google books, I was able to reproduce the gun and carriage for a 32 pound cannon. The details are a little different from ones more commonly found in the 1770s in a number of modeling books. The most obvious are that the cascable is shorter, with a compressed set of moldings behind the base ring. Also, the transom on the carriage is vertical over the fore axtree (which looks very much easier to build than the angled ones seen later). And the stool does not sit on a thick bolster, but rather a rather thin vertical plank. It looks a little fragile compared to later carriages.

 

I pasted my gun and carriage over a scanned image of a cross section showing the guns in Falconer's Dictionary of the Marine from the 1760s. The Armstrong/Muller details lined up almost exactly with the Falconer drawing. The only difference is that I had to reduce the height of the carriage body by about 1 1/2" to get the cannon at the right height relative to the gunport, matching the Falconer height (which is the same as the Bellona's). Also, the Falconer drawing shows an elongated neck for the ball at the end of the cascable. I could not find any other examples of this in other resources, so I stuck with the drawing in Muller's book. Interestingly, the drawing in the Muller book does not match the text, regarding the length of the cascable; the text calls for something longer than the drawing shows, probably getting closer to Falconer's drawing. But I could not draw this convincingly without further information. The text also explains a method for determining the length of the body, which does not match the length given in a table. Research from primary sources sometimes has its challenges!

 

I spent some time working out the dimensions for the cannon, relative to one origin. You will see one set of dimensions in purple, aligned to the first and second reinforce which is a 1 degree taper. The second set in orange aligns with the chace, whose angle is 1.5 degrees.  I hope to use this to turn a master on the lathe, and then try casting the 28 guns required.

 

Stay tuned!

 

Best wishes,

 

Mark