C.S.S. Hunley Scratch Build

[Fizbi]

Looks like I hit the jackpot...

I found a document that covers everything I been looking for. This includes recovery of the Hunley, engineering and archaeology drawings from many sources. Too many sources describe the Hunley "about XX" long. No facts.

I now have the EXACT numbers.

I consider this model an easy build. If you think about it, it's just a long cylinder with both ends pinched off. For me, I want to build it like the designer built it, with half panels, quarter panels, expansion strake, etc.

Clearly, many models of Hunley for sale sport poorly researched design and fabrication. The Hunley had flush-rivets that were countersunk into the hull. Why are so many models sporting standard industrial rivets that project out from the hull? No attention to detail would be my guess.

Easy build at first sight, but the research is turning out to be more fun. Reading up on the history and construction notes for the time will make this a far more interesting build than squeezing off the ends of a cardboard tube.

[Fizbi]

So it begins.

Hunley is a bit different than any boat I've ever seen. For starters, it has no conventional keel. The keel is actually made up of cast iron blocks that can be released by the crew in case of "accident". The keel (blocks, ballast) is attached to the hull with some kind of bolt or latch mechanism which has yet to be uncovered. Details have not been released yet. So, I will start here as I need to attach the hull to something. I think i will weigh down the ballast with some weight (maybe a few pennies) glued into the cardstock.

If details become available on how it was attached, I'll just update my drawings. So from my sketch, I'll start working on the keel (ballast, blocks) on my computer. Then, I will have something to add the lower hull half panels to, starting at the center and working my way towards bow and stern.

Since this is my first photo, this will help me size my photos for uploads.

[Fizbi]

Finished reading the Hunley Recovery docs and got my measurements.
I'm now torn between constructing a 1:15 or 1:20 model.

Either one gives me enough room to install internal components like wood bench, hand cranks, pumps, and flywheel.

1:15 produces a hull that is 814 mm in length, 90 mm H x 74 mm W
1:20 produces a hull that is 610 mm in length, 67 mm H x 55 mm W

Again, this is without the keel, rudder, propeller, spar, and torpedo.

I think the cardstock can handle the construction of either size.
Either way, it will be a massive model with a lot of detail.

I may build a crossection of hull consisting of one plate in length to get a feel for the complexity. Maybe that will help me decide.

[Fizbi]

Hunley Frames using InkScape at 1:20.
Hunley has several of these about every 2 feet where the hand crank supports are bolted to hull. I'm guessing they were put there to reinforce the hull against the pulling forces as the crew cranked the propeller.

Now I get to test my carving skills.

[Fizbi]

Reworking the frames. Here I located a recent image from the Hunley recovery. By creating my initial frames, I was able to go back in and resize a copy and overlay the Hunley image. Not perfect, but close enough to get a fairly accurate frame inside to outside measurement.

In this photo, the hardware for releasing the ballast is becoming visible. The bench hardware is now visible along with propeller crank. Fascinating stuff.

Almost ready. I picked up some glue, Z blades and scissors to try out.

[Fizbi]

Hunley has an amazing hand crank propeller system.
Now that more of the interior has been exposed, I see how the cranks were installed. I have wondered how in fact they could install such a long mechanical device.

I found an image showing better details. The cranks are in fact separate cranks bolted together at different angles. The cranks were attached to the panels with brackets, each crank interlocking with the next. Bolts held the cranks together as one long system.

While I work on the hull, I'm going to think how I can make a model of the crank system.

[Fizbi]

After playing with some printed out frames and practicing cutting out the shapes, I decided to go with 1:15 scale.

In the attached photo, I am practicing rolling paper and glueing to frame. I'm a newbe at this, so this is an important step in preperation for the real thing.

I'm using plain printer paper to test various glues. I found I can use the paint brush to apply light pressure to the frame as it is rolled and glued. I may build a jig to do this as it's a perilous balancing act with all the curved surfaces. Anyway...back to the store as white glue is too slow and the other glues I bought don't work in this case. I think the liquid tacky glue is better suited for what I'm trying to do. I may have to add some tabs but until I learn how the frames were attached, I don't want to add them to my drawings just yet.

[Fizbi]

Slow but steady progress. I have been trying to confirm the number of frames in the crew compartment. Studying all the photographs offered on the Internet is a confusing pile of information.

I finally made sense of it all when I decided to watch all the Hunley videos on YouTube. I located X-Ray images that had been digitized. The X-Rays show 9 frames, somewhat evenly spaced along the crew compartment. I can't get exact spacing measurements, but close enough for me to proceed. I can adjust my drawings as more details emerge. Hunley updates appear to be nonexistant in the past 12 months or so. The preservation process is taking longer than planned.

Anyway, the screen shot of my overlays show approximate frame locations at the guide lines. Getting there.

[elliott]

Slow progress is still progress.

[Fizbi]

Counting rivets. Believe it or not, I located enough photos of the Hunley to count all the rivets for the plates between the two hatches. I can now accurately place the butt straps where they belong. This also helps with creating a scale drawing with more accuracy.

Now, as I step back and look at my updated drawing, I see that Hunley has two sizes of boiler plates installed. Three that have 15 rivets and three that have 16 rivets. What was Mr. Hunley thinking? I mean really, there is just no even spacing here at all that I can find. This also raises questions about the frames as well. They are not spaced evenly either. They seem to be an after thought.

It's almost as if Mr. Hunley went out back to see what was laying in the yard and said, "Okay...just bolt them boiler sections together and we'll add internal frames as extra support".

Adjusting my drawings...