As I said in my very first post at the beginning of this thread, work on the Habakkuk will be slow. I need to get past the holidays first. Then I need to save up some $$ for more building materials. So in the meantime until more in-progress model pictures are ready, I shall regale all of you with more history about the Habakkuk.

As some of you may know, the Canadian National Research Council undertook in early 1943 (January to about April.) the task of building a 1/50 scale Habakkuk prototype on Patricia Lake near Jasper, Alberta, Canada. This "prototype" was NOT a scaled down version of a real Habakkuk vessel in any way. It actually looked like a house sitting on a lake. It was built by about 2-3 dozen conscientious objectors (Pacifists) to the war effort who built the "houseboat" model in about 2-3 months time. The model measured about 60 feet long x 30 feet wide x about 20 feet high. Contrary to popular belief, the model was not made with pykrete. Regular blocks of ice were cut from the lake and used in it's construction instead. The sole purpose of the construction of this model was to test various building techniques and materials in preparation for possibly building a full size Habakkuk vessel in the future. At the same time the Habakkuk prototype was being constructed, tests were being carried out at other locations such as Lake Louise, Banff National Park, and/or Lac Beauvert on regular (and modified - pykrete?) ice blocks and columns to see how well they could handle various stresses and what appropriate sizes would be needed in the construction of a Habakkuk vessel.
https://en.wikipedia.org/wiki/Jasper,_Alberta
https://en.wikipedia.org/wiki/Banff_National_Park
https://en.wikipedia.org/wiki/Lake_Louise_(Alberta)
https://en.wikipedia.org/wiki/Lac_Beauvert
Two other excellent sources of information on the Habakkuk prototype construction are "The Canadian Habbakuk Project" book by Lorne W. Gold, as well as a PDF document here by marine archaeologist Dr. Susan Langley.
https://www.academia.edu/8068147/Operation_Habbakuk_A_World_War_II_Vessel_Prototype
https://www.erudit.org/fr/revues/scientia/1986-v10-n2-scientia3221/800233ar.pdf

It should be noted that 2 myths about the Habakkuk prototype need to be corrected.
1. Three 10 hp (horsepower) motors were used to help keep the Habakkuk prototype cold/frozen. This is well documented in the book I mentioned above. It was not anything less than this.
2. Anybody who argues with me on this next point is going to get a serious thrashing.    The prototype DID NOT take two or more years to melt and sink to the bottom of Patricia Lake. According to Susan Langley's PDF document above on Page 126, by May and/or June 1943 a few months after final completion of the prototype, the refrigeration machinery was turned off and removed. The prototype sank to the bottom of the lake in mid to late summer..........THE SAME YEAR (1943)!

Back on Page 3 of my model thread here, there are pictures of what my 1/700 scale Habakkuk display looks like. I have been thinking of doing a similar large display for my 1/350 scale model: the Habakkuk, a second Essex carrier for scale reference, a German uboat for scale reference, a small interior cross section of the Habakkuk, and.............possibly adding a small model of the Habakkuk prototype house for scale reference too. But in 1/350 scale, the prototype house wouldn't have much detail to it and wouldn't be much to look at. It would only be about 2 inches long x 1 inch wide x 3/4 inch high. So it might be doubtful I'll build and add it to the final display. We'll see.

Wonderful history on something I previously knew nothing about, thankyou 

Quote from: NARSES2 on January 03, 2023, 06:18:02 AMWonderful history on something I previously knew nothing about, thankyou 

And that's part of my plan in this modeling thread: To discuss a bit of real history on Project Habakkuk as I go along to inform people about what Habakkuk was all about and what it wasn't. So from time to time in this thread, I will interject bits of real history and facts from all the research I've done recently in preparation for doing this large model project as well as what I've learned in the last several years since I built my 1/700 scale Habakkuk model.
So now the big question comes along: How will I build the main ship hull? As I've said way back in previous posts on Page 1 of this thread, there is no final blueprint/configuration of the Habakkuk vessel anywhere. Anything that has been drawn/shown is either a "proposed" (but not final) design, or it is a fantasy artist interpretation.
But the following main things are fairly consistant in most drawings and sketches:
a) Elongated hull. Mostly "blocky" shaped. Kind of like a very long rectangle block.
b) Both bow and stern ends are pointed and have basically almost the same shape/measurements.

Due to the long length (Almost 6 feet.) of this model, I am going to have to "cut it" in half for easier storage and/or transportability.
FIRST PICTURE BELOW: I will probably build the hull into 4 sections. The central 2 portions of the Habakkuk model hull will be 24" inches long each. I should also note that I plan to "cheat" on building this model.    To save time and/or other resources, I'm planning to hopefully have a plastics company near me make the two central hull pieces. Whether or not they can depends on the costs involved and/or any technical issues that may arise in making the two pieces. As for each pointed end, I'm not sure on whether I will build that myself or have the plastics company make them for me. The hard part about the end pieces is getting all the angles and dimensions just right so that every angle meets perfectly. Know what I mean?
SECOND, THIRD, & FOURTH PICTURES BELOW: Once I have the central 2 hull pieces made, if you look at them head on, this is what they will most likely look like. Hollow in the middle. Kind of like a hollowed out brick or square. The measurements for how tall and wide they are are approximate. I am off a little bit by 1/32" or 1/16" inch slightly as I tended to round up or round down my measurements to the closest 1/4", 1", or whatever. Notice the "angled notch" in the lower left and lower right corners of the hull cross section in the second picture. This is fairly consistant in a lot of drawings and schematics I've seen and runs pretty much the entire length of the hull. And it is also backed up and mentioned in "The Canadian Habbakuk Project" book, but I don't remember on what page I read it. If I build the pointed ends of the model myself, getting the angle of the notch correct will be tricky.
Measurements:
20 feet in 1/350 scale = 0.68". I rounded up to 3/4" inch.
40 feet in 1/350 scale = 1.37". I rounded down to 1 1/4" inches.
200 feet in 1/350 scale = 6.85". I rounded down to 6 3/4" inches.
300 feet in 1/350 scale = 10.28". I rounded down to 10 1/4" inches.

Something that I will most likely not put on my model is a rudder and/or skegs underneath the stern. As you can see in the sample illustrations below, there were plans to eventually put a rudder on the Habakkuk. But due to technical difficulties and design issues in trying to attach a 100 foot tall rudder to the Habakkuk and controlling it, adding a rudder was dropped by the designers and engineering staff.
As for whether a real Habakkuk ship was to have 1 rudder or 2, or 1 skeg or 2, there is no information on this. But I strongly suspect it would have been 1 rudder and 1 skeg only as shown in the lower right corner of the second picture below, with the rudder and skeg situated in the center directly underneath the pointed stern.
So if the designers and engineers couldn't figure out how to have a rudder on the ship, then there's no point in me adding one to my model since I'm trying to build a model as historically correct and technically believeable based on all research I'm doing. I "might" add the skeg on the model. But probably not the rudder.
So just how was the Habakkuk ship supposed to steer itself? One possible solution (and I'm not sure how well this would have worked) that I've read about was to vary the pitch of the propellers on the motor nacelles on either side of the hull to help steer/turn the ship. Increasing the pitch (rotation) of the propellers on the left side of the hull and decreasing the pitch on the right side would (or should) hopefully make the vessel turn right. Increasing the propeller pitch on the right side and decreasing the left side would hopefully make the ship turn to the left. Or so the theory goes. 
Even if this were accurate, the Habakkuk only has a top speed of no more than 6-7 knots which is like a slow crawl. So to complete a full turn might take a very wide/big radius which could be dozens of nautical miles. So trying to "turn into the wind" to help launch aircraft is going to be problematic. This is why aircraft catapults would most likely be added/used on the ship to help launch aircraft.
 

Moving right along...........

From most references I've read, a real Habakkuk vessel was designed to have 26 motor nacelles (13 on each hull side) to help propell the ship. To get the 6-7 knot speed for the Habakkuk, it was envisioned that a total of about 32-33,000 hp would be required. This would be approx. 1,250+/- hp per motor nacelle. The propeller diameter would be 14 feet and the rpm would be 110. The propellers would also be 3-bladed.
The drawings below come from an article titled "HABAKKUK" by William J. Wallace in WARSHIP magazine which I already listed in my first post back on Page 1 of this thread.
The first picture below is the only decent rendering of what the motor nacelles were supposed to look like. I have not been able to find any other accurate drawings.
As you can see in the first picture below, the motor nacelles (without shaft bracket and propeller) were designed to be 60 feet long x 25 feet high x 18 feet wide, and have what looks like a teardrop shape to them.
In 1/350 scale, the nacelles would be approx. 2" inches long x about 3/4" inch high x about 1/2" inch wide.
When I built my 1/700 scale Habakkuk model long ago, I used modeling clay to make the nacelles. Another modeler made the propellers for me, and the shaft brackets were scratch built by me. But for my 1/350 scale model, I'm going to see if I can get the nacelles, propellers, and shaft brackets 3D printed instead.
In the second picture below, you can see how the motor nacelles would be arranged on either side of the ship hull. The blue line is the waterline.
The red line is the first line of motor nacelles about 50 feet below the waterline. At least 6 nacelles in this row.
The green line is the second row of 5 nacelles which are 30 feet below the first line of nacelles, or 80 feet below the waterline.
Notice how the nacelles are spaced 200 feet apart in each line.
But, there's a problem. Looking at the very back of the ship on the left side of the drawing above the skeg/rudder, you can see two motor nacelles which don't line up with the red or green nacelle lines and are attached to the angled pointed end of the aft hull. Yes, from all drawings and references I've looked at, it appears these nacelles were to be placed in these positions. Since they don't line up with either the red or green lines, I'll have to figure out a way to best position them so that the nacelles on the left side of the hull accurately match up to where the ones on the right side are.
P.S. - How can I best explain this?    Notice how the red and green lines go through the "center" of the motor nacelles. So when I attach my nacelles on my model, the first line (red) of nacelles is measured 50 feet from the waterline to the "center" of the nacelle. Not from the waterline to the top or bottom of the nacelle. Same thing for the green line: waterline to the center of the nacelles.

Well, I'm going to be home sick the next few days     and on antibiotics which means I may write a few more posts about the Habakkuk. Unfortuneately what it does not mean is that I can't go out to the hobby store and get more supplies to continue any sort of construction. 
So, with that being said, here's a short synopsis on how I may show off the completed Habakkuk model project when fully done.
As you can see by the first picture below, that is of my older 1/700 scale Habakkuk model I built long ago. To convey a sense of scale, I included a 1/700 scale Essex class carrier painted black to act as a silhouette, and also included a small 1/700 scale German uboat. Also added on the far right was a small cross section cutaway of the Habakkuk hull.
When my 1/350 scale model is ultimately done, I am heavily thinking of displaying it in a similar manner. But since the 1/350 model has to be split in 2 pieces for easier storage and transportability, so too does the display base for it.
So I'm thinking of having the following items on the display base along with my 1/350 scale Habakkuk:
a) 1/350 scale Essex carrier for scale comparison. Again painted black.
b) 1/350 scale German uboat (and torpedo) for scale comparison.
c) A small selection/sample of various US and/or UK aircraft that could be used on the Habakkuk.
d) Again, a small cross section cutaway showing the interior of the Habakkuk hull.
e) Maybe show a small 1/350 scale model of the Habakkuk prototype "houseboat" that was built on Patricia Lake?
f) One or two data specification information sheets.

Of course, having any or all of the above items on the display base along with the main Habakkuk model will make the display that much more crowded, heavier, and larger which will make it possibly more difficult for storage or transport. So I'm really not sure how much I'll really add. 
What I do want to do is place the main Habakkuk model (and/or other stuff) on a clear sheet of acrylic. This will make it look like the Habakkuk is sitting on a sheet of ice. Well, the Habakkuk will actually sit on a bunch of clear acrylic "keel blocks", or maybe I should just call them ice cubes. 
By having the model on a clear acrylic base/keel blocks, I think this will enhance the overall appearence of the display quite wonderfully. 

That sounds great 

Gondor

Quote from: Gondor on January 09, 2023, 03:18:21 AMThat sounds great 

Gondor

Does indeed 

Hope you feel better soon 

Just a small update:

Work on my Habakkuk is temporarily on hold until I can secure the necessary funds to go to a plastics company and get them to fabricate the hull pieces for me.
But if the price they quote me is too high, I may have to build the hull myself. Anyway, hoping to have more information and decisions later this Spring.
Otherwise, if anybody has any questions about my build, the design process, etc., etc., then ask away and I'll answer as best I can.

As you are going to use Clear Acrylic for at least part of the disply base, will you be calling that "Plastic Ice"?

Gondor

Quote from: Gondor on February 12, 2023, 08:22:09 AMAs you are going to use Clear Acrylic for at least part of the disply base, will you be calling that "Plastic Ice"?

Gondor

I don't know. Maybe?

Just a tiny update to say there is no progress on my Habakkuk project. It is still on hold due to financial reasons that I mentioned in a post further above.
Got to see if Congress passes a debt ceiling bill. (Need a miracle for that.) If they don't, then millions of Americans get screwed and my finances go toward more important things other than modeling.    And I'm still trying to save money for the IPMS Nationals next year which has a slightly higher priority than saving money to get the Habakkuk hull made by a plastics company.

I like the idea of having all of that on the display. The u boat and torpedoe is a great idea.

Long time, no post. Sorry about that. The Habakkuk model itself is still on hiatus due to financial reasons.
But............I'm thinking I may start on some other stuff. Like getting ahead of myself and start building the small 1/350 scale German u-boat and a Trumpeter 1/350 scale ESSEX aircraft carrier for scale reference that I plan to display next to my Habakkuk model like I had mentioned in my earlier Post # 65.
The small German u-boat (Picture attached below.) will be built and painted as is. No modifications to it at all. Though I may add a small torpedo next to it for scale comparison also.
But for the Essex carrier, should I still paint that black to act as a silhouette against the backdrop of the much larger Habakkuk model? Or should I paint the ESSEX carrier in it's normal WW2 colors?
I'm not going to detail the ESSEX carrier all that much. No weathering, photoetch, or a lot of other details. It will be built full hull though. Not waterlined. What I really want is for people to focus their eyesight/attention on the Habakkuk model itself. Everything else around the Habakkuk model on the display board is just for scale comparison mostly.

In other news............
From time to time in my research on Project Habakkuk, I have heard and read from a few resources where people say the Habakkuk was going to be (or supposed to be) much larger with a length of anywhere from 3,000 to 5,000 feet and a width of 500 or more feet.
This is pure rubbish! 
The final and official dimensions of a proposed Habakkuk vessel (Hull only without the attachment of the motor nacelles.) were to be 2,000 feet long x 300 feet wide. Converting that to meters, it would be 610 meters long x 91 meters wide.
Where people are getting these crazy notions that the Habakkuk was to be much bigger, I have no idea. But I have a few guesses.
When Geoffrey Pyke was first envisioning using floating large chunks of ice/icebergs for use a airfields in late 1942, he may have just been "day dreaming" for lack of a better word before any real research and design work had been carried out by engineering and technical staff. As he began to tell various people about his early plans and fantasies, the idea of really large (3,000 or more feet) ice airfields probably got sensationalized and spread about before more conservative military brass and others finally brought his fantasies a little bit more "down to earth" so to speak.
Second, when Pyke first proposed his floating ice airfield ideas to Lord Mountbatten in late 1942, he wrote a very lengthy memorandum to Mountbatten describing his ideas. Mountbatten then submitted Pyke's ideas to Winston Churchill for consideration. Churchill appeared to be very enthusiastic about Pyke's proposals. So much so, that he wrote a memorandum to General Ismay on Dec. 7 which read in part:
"I do not of course know anything about the physical properties of a lozenge of ice 5,000 feet by 2,000 feet by 100 feet, or how it resists particular stresses, or what would happen to an iceberg of the size in rough Atlantic weather, or how soon it would melt in different waters at different periods of the year."

Whether or not Churchill actually said the above quote in his memorandum to General Ismay, I do not know as I don't have access to the original memorandum. But what I quoted is from Page 11 in Lorne W. Gold's book "The Canadian Habbakuk Project" which happens to be the best book reference anywhere that goes in depth concerning the history and engineering aspects of Project Habakkuk. So if Mr. Gold put part of that Churchill memorandum in his book, then I guess it must be true what Churchill said.
So I guess it stands to reason that as time went by, people probably got confused about the Habakkuk's true size not just from Pyke's fantastical tellings, but also from part of Churchill's memorandum. Only later in 1943 when more design work on Project Habakkuk was fully being undertaken were final official dimensions of 2,000 feet x 300 feet settled upon for the vessel.

My personal opinion is to paint the Essex as she was, as even that level of detail will add to the impression of Habakkuk's scale.

From the wording used, Pyke & Churchill were talking about floating "airfields", what the Habakkuk proposal ended up being was a huge aircraft carrier, which is not quite the same thing.