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Cathead

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About Cathead

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    Eric
  • Birthday 09/08/1979

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    Missouri, USA
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    Ecology, history, science, cooking, baseball, soccer, travel

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  1. Roger, I think the reasoning I posted when you first shared that image still stands: I don't think it'd be wrong to do as you say, either, as Arabia does fall into that grey zone of development (early in the period when designs really stabilized for the next few decades). But overall I seem to be modelling her as a relatively modern vessel incorporating most of the new design ideas of the 1850s onward rather than as a throwback to rapidly evolving 1840s designs, so in that sense I think I'm comfortable keeping the transverse chains below the boiler deck. I really appreciate your input, though, it's helpful to be challenged to think through and justify the choices I'm making (if only to myself).
  2. Sampson posts went out of use before this period, they were an early style only. There won't be any trussing above deck other than the regular superstructure.
  3. Roger, Both Louis Hunter and Adam Kane note that longitudinal hog chains were first developed in the 1840s and probably weren't in widespread use until the 1850s. So their apparent absence in your 1848 photo isn't necessarily indicative of their use or not. Both of those resources, as well as Bates, make blanket statements that sidewheelers used longitudinal hog chains, but that once the engineering had been worked out (i.e., probably by the mid-1850s), they tended to remain below the boiler deck and thus wouldn't be easily visible in photos. But they'd be visible on a model viewed from the side. So I think I'm well within reasonable modeller's license to install them on Arabia. Bates also notes, in a passage I missed until rereading carefully, that some boats' knuckle chains (those supporting the hull) remained below the main deck, which is a good enough reason for excluding them above-decks on Arabia. In several re-readings, I can't find a clear answer on the use of cross chains (supporting the guards) for narrower non-cotton-packet boats like Arabia. It's obvious they were abundant on wide boats, but no one really discusses their uses on other boats. A clear argument could be made that Arabia didn't need them other than near the wheel, but also that a cautious builder or owner might have had a few installed further forward for greater strength. As for the hog chains, I think reasonable modeller's license allows the judicious inclusion of cross chains in the model for visual and historical interest.
  4. Real planking always looks better. Are you leaving it the natural wood color or planning to paint/stain the typical red color?
  5. I think the single biggest mistake newcomers make is getting in over their heads. You do NOT have to start with a big rigged ship. Building one or two small craft (rowboats, launches, fishing vessels, etc.) will let you test almost all the skill sets, methods, and materials you'll need for your dream build, and they're a cheaper and faster way to go about it. The time you "waste" doing that first will almost certainly be saved in the long run when your dream build goes faster and smoother once you know what you're doing. The second biggest mistake is being cheap and looking for deals rather than focusing on quality. Lots of people get frustrated when they buy a random kit that looks pretty but is poorly made with terrible instructions, because they didn't bother doing some basic research on which manufacturers are actually worth buying from. Also, there's a risk to working on older kits, because materials can age poorly and kit quality has improved. It may feel good to dust off that 20-year-old kit you always wanted to build, but there's a very good chance a kit made last year will be a lot more pleasant to work on.
  6. Mark, as I said above, upper-river boats needed hull flexibility and lightness to deal with shallow-water conditions, which is why I would expect them to rely on chains as much as or more than hull bracing. However, that doesn't mean they needed lots of them, given their relatively light hulls and cargoes. Lower-river boats could afford to have more interior hull bracing (and thus more rigid hulls) because of calmer and deeper river conditions. They still needed chains to help support those huge hulls and their extreme length-width ratio, but especially required lots of transverse chains to support their extra-wide and heavy guards (see Kurt's images of the J.M. White, above). My conclusion from all this is that something like Arabia wouldn't have had as extensive a network of chains as you see on the J.M. White, but likely still needed a few to support the needed hull flexibility of an upper-river boat. I.e., Arabia shouldn't look like a spiderweb, but should probably have a few transverse chains near the wheels and possibly one or two further forward, then one or two longitudinal chains to help support the hull's flexing over sandbars and such. I had no idea this would generate so much discussion, maybe I should have put this question in the general riverboat thread. Oh well.
  7. Carl, from my perspective (and I'd be interested in Kurt's and Roger's input), the internal bracing and the hog chains serve slightly different purposes. Internal bracing makes the hull more rigid, which is particularly useful in ocean-going vessels but potentially problematic in riverboats because too much rigidity means you can actually break the boat's back in shallow-water river conditions (this would be less of a concern for deepwater steamboats on the lower Mississippi like the big cotton packets). The chain system allowed for a certain amount of hull flexibility that was needed in these conditions while still providing support; it also meant you could readjust the tension needed as the boat worked and aged. So most boats, especially by the 1850s, used a combination of both as relying on one or the other exclusively would be problematic. Also, extensive wooden bracing gets heavy and expensive rather quickly, and upper-river boats needed to be light and cheap. A few iron iron rods were a lot more practical in this sense than lots of custom-cut oaken braces. Finally, upper-river boats tended to carry proportionally more cargo in their holds than the bigger lower-river boats with their huge stacks of cotton on deck. Among other things, this kept their center of gravity lower, an important consideration in the very windy conditions of the middle and upper Missouri River. Thus, transverse bracing especially quickly eats into both the available space and the navigability of the already shallow and narrow hold, whereas chains are smaller and easier to work around. So while there's no doubt something like Arabia had internal bracing in her hull, my instinct is that it wasn't sufficient or even desirable to have a full web of bracing down there, making chains a realistic alternative.
  8. Carl, all that sort of thing refers to interior framing within the hull, beneath the main deck. None of it would be visible on this model's closed hull.
  9. Roger, That's a great and rare early image. The resources I've read (like Bates and Kane) all note that early sidewheelers like this one had tall support posts as shown here, but that by Arabia's time these were mostly kept short (i.e., under the boiler deck) and so wouldn't have been visible in any exterior photo. Same goes for longitudinal chains, one of the reasons it's so hard to use later photographs as evidence for anything in this regard. I think that photo nicely documents the fact that not all boats inherently had a full set of transverse chains, as in an early craft like that they would be visible as higher posts. That vessel seems to have narrow wheels and guards, like Arabia, thus needing less lateral support. I'm a little surprised it doesn't show longitudinal chains given how long that hull is, but it's also early enough to predate the full adoption of hog chains and still falls in the highly experimental period of steamboat design. Right now my leaning is to put in two sets of transverse chains fore and aft of the wheels, maybe 10' apart. I still feel like some kind of transverse chains would be necessary to help strengthen the hull further forward for similar reasons as Carl's post, even if it's only one or two sets, so I'm playing with the idea of putting in a couple where they can been seen as visual interest. I'm going back and forth on the longitudinal chains; I like Kurt's suggestion of two (one on each side of the hull) despite Kane's claim that this was mostly done as one down the middle, because it actually makes more sense with the geometry of the hull and superstructure. Overall, as Arabia was built for the Ohio River but later transferred to the Missouri, it wouldn't surprise me if she was initially built with minimal hog chains but was retrofitted with more for the latter river. Navigating the upper Missouri required extensive encounters with sandbars and extremely shallow water, meaning that the hull of such vessels was subjected to extreme flexing as they literally slithered over the bottom. Thus I think it's reasonable to conclude that she may have had more chains than a lower-river boat to help hold the hull together under such conditions. Thanks to everyone for the input, it's been extremely helpful in thinking this through.
  10. So glad to see the two of you back to work together. Lovely job cleaning up the hull.
  11. Kurt, here's what Adam Kane (not Bates, faulty memory on my part) says on the subject: That's what I was basing my plan on; it puts the forward end of the chain right at the main stairwell. What do you think? This makes sense to me as it places the line of support directly along the keelson (though I'm sure it was done various ways as with most things on these vessels). Another thought on the transverse chains is that I'm building Arabia, like the Ben Campbell, to have a boiler deck that extends out to cover the main deck over most of the length (unlike the big cotton packets), which also provides more bracing and support overall for the guards even while it adds a bit more weight as well. Which again implies, as you say, that I just need a few chains around the wheels.
  12. Kurt, You're certainly right that Arabia wasn't a cotton boat but one built for the upper rivers; if nothing else this is shown by how narrow her wheels and guards are. So your thought is that I shouldn't bother with any transverse chains except maybe in front and back of the wheels? And those would be cross chains (going out to the guards) rather than knuckle chains, since the cylinder timbers block the latter? I'd looked at that Ben Campbell photo and those I have of the Mary McDonald because these (as you say) were pretty similar to Arabia, and hadn't seen anything, but thought that was just because of photo resolution/detail. It'll certainly make the build easier to not have to add these! What about longitudinal hog chains? Bates says sidewheelers usually had a singe one running down the centerline, just below the boiler deck, making it nearly invisible. Is it worth trying to add that detail? I assume it'd have to anchor just behind the main staircase, run up between the chimneys, then hang from the center ridgepole the rest of the way aft. It'd be really hard to see but if it was likely there, seems to me I should try to simulate it. What do you think? Also, am I missing any other main deck detail I should include before attaching the boiler deck and intervening superstructure? I'll add hatches and winches to the bow later, and that's open anyway.
  13. You people are evil, encouraging a second model. It ain't happening until this one is done at the very least. That's not quite right; all the machinery I've built so far can be seen on a fully finished model because the main deck was mostly open to the side. It'll be somewhat obscured, but if I left out any of the detail of what I've built it would look wrong when you gazed on the model from the front or side. Even in the shadows, you need to be able to see the engines, driving arms, etc. The only thing I could skip in a fully finished model is a full wheel, and I already did that on the port side. So the only difference in a "wreck" model would be that you'd see the machinery more clearly without a deck above it. I wish it were otherwise! Moving on, here's the design question I mentioned last time that I need some input on; it relates to the internal bracing. Riverboats used extensive networks of "chains" (actually iron rods with turnbuckles) to keep the hulls from warping. On sternwheelers, the main concern was "hogging", or longitudinal warping, in which the hull tended to flex down at the bow and stern and rise in the middle, especially due to the weight of the engines and wheels right at the stern. Thus the main set of bracing on sternwheelers were hog chains, running longitudinally along the hull and rising above the decks. However, on sidewheelers the biggest concern was sideways warping due to the weight of the wheels hanging off the sides and the wide decks, especially the guards (the deck extensions beyond the main hull). So sidewheelers had a lot of lateral bracing, depicted by Alan Bates like this (I hope it's ok to post this image, I don't know how to explain this without using a Bates drawing). So you see two kinds of visible bracing: the knuckle chains that support the edges of the hull, and the cross chains that support the guards. Pretty straightforward. My question is, how were these spaced along the length of the hull? Although I can find versions of this cross section in various sources, I can't find anyone explaining how many of these were used along the hull's length. Every 10'? Every 20'? How did they interact with major features like the boilers and engines that block their path as shown above? I can't find a diagram or text that deals with this question. Here are some mockups on the Arabia to show what I mean (the boiler deck is just set in place for reference, not attached). Here I've placed scrap wood at the approximate angle of both knuckle and cross chains, at an approximate 10' spacing along the forward hull. But I have no idea if this is right. Note how close the knuckle chains come to the boilers and how the engines essentially block their use. Kurt, Roger, anyone else knowledgeable, I'd love some perspective on the right way to arrange these.
  14. Very nice! I'm going to reference that pilot-house wheel when my time comes.
  15. Steve, you're closer than you know. When I was out on the porch yesterday taking photos for that update, I had my Kindle as well, loaded with the reference photos I was using to get those paired images from the same angle. I set it down on the railing above the model and almost lost my grip; it would have dropped a couple feet straight down onto the port wheel and machinery, bouncing into who knows what else. I really don't know what I would have done in that circumstance.

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