CONSTRUCTION PLANS

The construction plans laid out in my small workshop.

While I can never be certain that my plans are precisely correct, I believe, given the available historical sources, that they represent a reasonably accurate representation of HMS Terror as she was fitted for her final 1845 voyage. Certainly, much research remains to be completed on specific details (e.g. colour scheme, masting and rigging, hardware, name and cipher(?), etc.), but now that I’m satisfied with the accuracy of the ship’s general profile and dimensions, I can move to creating construction plans for a plank on bulkhead model.

I created the plans directly from the inboard profile and body plan, using a method similar to that outlined by Rich Brayshaw. The stern configuration from the sternpost to the rudder will be recreated just as it was designed in the Terror’s 1845 stern modification plan, and the keel, false keel, stempost, stemson, and knee will be constructed in a similar manner. The false keel structure will be made from 1/4 inch (6.35 mm) plywood, which matches the exact scale width of the sternpost and keel. The slots in the false keel descend to the load waterline, and will accommodate 21 bulkheads, corresponding to each station on the plan. While this might seem overkill for a 1:48 scale model of a small ship, it will give a very solid base for the planking, and I believe it will generally result in a more accurate model. You may notice that the height of the false keel doesn’t line up exactly with the inboard profile plans; this is because I modified it to account for the deck camber (derived from the 1839 Terror and Erebus cross section plan).

Note: This plan has intentional errors to discourage commercial copying. 

The bulkheads (which represent all the stations) may seem quite unusual to those who work with plank on bulkhead models. This is because each includes a precisely faired outline of the solid chock channels that surrounded the ship. The 1839 Terror and Erebus cross section plans show that the channels actually sat on the first layer of planking, and I considered recreating this, but quickly dismissed it. My reasoning is that, after a first layer of planking, it would be very difficult to line up the channels to create a perfectly symmetrical model. As a result, I’ll apply the first layer of planking around the chock channels (they will actually help me align it), then plank the channels, then apply the second layer of planking (recall that both the Terror and Erebus had double deck and hull planking). The bulkheads will be cut from 5mm plywood.

Note: This plan has intentional errors to discourage commerical copying. 

 There is something very tangible to me about rolling out a freshly printed sheet; the plywood is now being pressed to remove any bends and twists; cutting starts this weekend!

PROOFING THE PLANS: PART II – THE LOCOMOTIVE ENGINE

One of the major innovations of the 1845 expedition was the conversion of HMS Terror and Erebus to auxiliary steam power (Battersby and Carney 2011).  On his blog, Peter Carney has documented his research on the locomotive engines used in this conversion; he later published his findings in the International Journal for the History of Engineering and Technology (Battersby and Carney 2011). To me, his research strongly indicates that the locomotive engines were not the Planet Type as has traditionally been assumed (e.g Cyriax 1997), but rather the Croydon and Archimedes engines built by G & J Rennie in 1838 and 1839.

 

Based on Carney’s research, I originally utilized a plan published in Brees (1840:133) which was labeled as the “Croydon” engine. However, in a recent email correspondence, Mr. Carney pointed out that this image was probably incorrectly attributed by Brees. The issue lies in the wheel arrangement and cylinder position. The image I based my locomotive plans on depicts a “0-4-2” engine with outside cylinders, while the Croydon was likely a “2-2-2” engine with inside cylinders (Bradley 1963; see also Carney’sblog). Mr. Carney believes the image I based my plans on probably depicted the “Hercules” engine, which was an assistant engine while the Croydon and Archimedes where passenger locomotives.

 

I always suspected there was something wrong with the locomotive I used in my original plans. If you look at my previous profile plans, the cylinders actually overlap the position of the spare rudder. Given that the modifications to the 1836 Terror plans show the exact position of the new engine room walls, this obviously could not have been the locomotive installed in 1845 (i.e. the locomotive was simply too big). Mr. Carney kindly pointed me to another image drawn by Brees (1840:306) which is unnamed, but which depicts a 2-2-2 locomotive with inside cylinders that was built by G & J Rennie – a good candidate for Croydon or Archimedes.

Using this new plan and an excellent set of drawings that Mr. Carney created and kindly provided (see his 3D reconstruction), I created my own scale plans of the locomotive. Using the dimensions from Bree’s (1840:14) original report, I scaled this new plan to exactly 1:48 and placed it in the proper position. As you can see, it fits perfectly, with just inches to spare on either side of the engine. To me, this exact spatial correspondence just adds credence to Carney’s theory that Archimedes or Croydon was the locomotive installed on HMS Terror.  

 

My new plans of the G & J Rennie engine, based on Brees (1840:306),
following the research of Peter Carney. The frame is speculative.  



   

 



INCORRECT - My original plan using the Hercules (?) engine. Note
the overlap with the spare rudder.

 

CORRECT? - The new engine in my updated plans.

 

Because of the new locomotive engine, the position of the funnel and steam outlet changed significantly, and these are depicted on the new deck plans. Given that the locomotive was only used in calm conditions or to avoid beating, it is likely that the chimney and steam pipe were removable, to conserve space on the crowded deck (Battersby and Carney 2011:202). As a result, I believe a scuttle or hatch system was used when the chimney was not installed, and I based these on one shown in the 1836 Terror deck plans (I have been unable to determine what that 1836 hatch was originally used for – the furnace chimney was apparently installed at the fore hatchway).




The positions of the chimney, steam pipe, and their hatches on my old plans.

The positions of the chimney, steam pipe, and their hatches on my new plans.

Finally, I should note that on my plans the height of the engine’s chimney and steam pipe are based on the following contemporary description (which also accurately describes the location of the chimney and the steam pipe):  

*  Note: Rather than post yet another set of updated plans, I’ve simply updated the plans on a previous blog post. The images have begun to be indexed on search engines and I don’t want to create confusion!

 

References:

Anonymous,

1845    Literary Gazette Journal for the Year 1845. Robson, Levey, and Franklyn, London.

Battersby, William, and Carney, Peter

2011    Equipping HM Ships Erebus and Terror, 1845. International Journal for the History of Engineering & Technology 81(2):192-211.

 

Bradley, D.L.

1963    Locomotives of the South Eastern Railway. Solihull: Railway Correspondence and Travel Society (1):11–12.

 

Cyriax, Richard, J.

1997   Sir John Franklin's Last Arctic Expedition: The Franklin Expedition, A Chapter in the History of the Royal Navy. The Arctic Press, West Sussex.

 

PROOFING THE PLANS: PART 1 - CONTEMPORARY IMAGES

Over the past several months I’ve received some great feedback on my research into HMS Terror from the model shipwrights on Model Ship World. However, before finalizing the construction sheets, I felt that that it was important to ask the opinion of some Franklin expedition historians.


A few weeks ago, I took the opportunity to contact two of the most knowledgeable experts on HMS Erebus and Terror, William Battersby and Peter Carney. Both maintain their own blogs and have published on the ships in peer-reviewed journals (Battersby and Carney 2011). Moreover, both are true gentlemen; they kindly took the time to read through my blog and offered some very useful advice on my plans.

Mr. Battersby suggested that I look again at a drawing from the Illustrated London News (ILN) which depicts Franklin’s cabin on HMS Erebus. He pointed out that there appears to be a cabin stove with a straight chimney on the extreme left of the image, which I did not include in my plans. The image seems reasonably accurate; the number and position of the windows and the shape and size of the stern lockers and superstructure matches the 1839 plans perfectly. As a result, I’ve modified my plans to include this stove; I based its dimensions and shape on what can be deduced from the image. The chimney for the stove is based on an 1839 image of a cabin stove available from the National Maritime Museum archive, and the height of the chimney is based on tables from Lavery (1987:291). Incidentally, the height of the chimneys for the ship’s stove and furnace are based on information in Lavery’s book as well.

 

Cabin stove and chimney detail.

Mr. Battersby also reminded me that a (very early) 1845 daguerreotype image of one Franklin’s officers, Lt. Henry le Vesconte, was taken on the deck of HMS Erebus. I’ve scrutinized it many times before and it’s a remarkable image which should be included in any blog about the ships. Le Vesconte is sitting on the starboard side of the Erebus (note the image is often shown backwards) next to the compass table in front of the mizzen mast. The photo confirms that the position and design of the skylight, mast, and wheel remain unchanged from the 1839 plans, and may also show part of a small deck house further aft on the starboard side (it appears to have a black door).

Mr. Carney also provided some extremely helpful insights. He pointed out that another image from the ILN shows two white deckhouses at the stern of both ships (note they also have black doors, just as in the Le Vesconte image). These were most likely water closets and signal lockers, and in my original plans I kept these quite low (almost the height of the bulwarks), based on an 1845 image of Erebus drawn by Owen Stanley. However the perspective used in his sketch probably foreshortens the height of the deckhouse and is not a reliable guide. 

 



 

Following the ILN image, I modified the deckhouses to be the same height and size as the single deck house shown in the 1839 plans. It is unknown if both were water closets or if one was a locker of some sort, so, in keeping with the original 1836 and 1839 plans, I am assuming that only one water closet was built for this voyage (only one water closet was used on Terror’s first two voyages, and the Terror had roughly the same crew compliment on all three polar voyages). I placed the water closet on the starboard side, following the suggestion of Battersby and Carney (2011:204) and based its design on the 1839 plans. I turned the other deckhouse into a locker for signal flags and other equipment and I admit its interior design is entirely speculative. Regardless, the model will have single black doors facing forward as is displayed on the ILN image (and which appears to be shown in the Le Vesconte daguerreotype). I should also note that both HMS Investigator and HMS Enterprise (1848 Franklin search vessels) shared many design similarities with the Franklin ships and both had twin deckhouses roughly the same size and shape as I have shown on my plans. In fact, both of their deck plans show the water closet on the starboard side of the vessel.



The new deckhouse profile, based on the 1839 plans.

Detail of stern water closet and signal lockers.



I should note that Peter Carney has also produced an excellent 3D model of James Fitzjames’ cabin, based on another contemporary image from the ILN. I did not include this structure in my plans as it was never depicted in any of the profile sheets (it is shown on the deck plans).  

Finally, I must point out that the daguerreotype discussed above isn’t the only one that might show part of the ships. William Battersby has provided some interesting analyses of reflections in James Fitzjames' cap, which reveals some interesting details of one of the ships. Russell Potter, another Franklin blogger, has also written some very interesting posts about the reflections in the highly polished caps of the Royal Navy officers, which show the rigging and perhaps the ship’s boats (compare the reflection in the cap to the position of the ship's elevated and upturned boats near the mizzen in my profile plans). 

 

*  Note: Rather than post yet another set of updated plans, I’ve simply updated the plans on a previous blog post. The images have begun to be indexed on search engines and I don’t want to create confusion!

 

References:

Battersby, William, and Carney, Peter

2011    Equipping HM Ships Erebus and Terror, 1845. International Journal for the History of Engineering & Technology 81(2):192-211.

Lavery, Brian

1987    The Arming and Fitting of English Ships of War, 1600-1815. Conway Maritime Press, London.