If you decide on 400-size motors, the lil tiny cast 1-into-2 gearbox that Greg designed would save a bunch of weight in the drive section. They're not terribly spendy, either, once I get around to pricing them
Hey Tugboat, has anyone tested Greg's 1-into-2 gearbox with a 400-size motor? I'm curious 1) can it get a destroyer up to fast-gun speeds, and 2) what kind of voltage and amps does it need? Only on the American and British ships. On the others, we'll be counting every gram
I sent you a PM this afternoon; let me know if you received it. If not, my e-mail is simply my forum name here at gmail.com
myforumnamehere@gmail.com? rediculous! Carl, are you planning on building one of the "proof of concept" boats?
Yes, Tugboat, I am planning on building one of these "proof of concept" boats. At least, I plan on assembling the hull. We'll see how much more I can do with this year's naval budget. Emile Bertin isn't the only ship scheduled for construction this year, and with the Maker Faire and the probability for new recruits, I might just move from "beta testing" to "initial release" after the hull is put together. After all, what better way to find out if our idea here works than to mentor a rookie and help him/her put it together? No guarantees that it'll have the originally planned armament, though...
If you want to do the testing (to see if one 400 can get a DD to speed), I have several of the gearboxes; I can send one for testing with the box'o'turrets. You might have to try different pinion sizes, but it's a start.
Going back to the Torps. I don't know about the rules that you are playing with, but in Big guns the tubes need to be 1/2 inch apart, just like the cannon barrels in the main turrets.
Hey JRodgers: I have noticed that there are a number of MOGs and a Volta or two floating around. I am one of the folks with a MOG. I have had a lot of fun in my efforts to arm the MOG. So far I have been un-successful! Of course, I am working on arming the turrets as well as the forward torp turrets. There is just not enough room to arm the stern torps. I have found that I am always looking for smaller batteries to save on weight. I am now getting concerned as to how much sailing time I will have before I drain the power.
I finally had a chance to take a good look over the Gearing drawings last night/this morning and thus far, only two thoughts main thoughts have come to mind: "I forgot how tiny the little tin can really is" "What have I gotten myself into" Anyhow, since the Gearing class is the smallest of what we've been discussing here as far as I can tell, I'm going to go ahead and start chipping away at building an initial 3D hull model in CAD as soon as I get the opportunity (I may mix it up between the Emilé Bertin superstructure and the Gearing hull for a while). In the meantime, brainstorming our options for weight reduction/control for the design of the Gearing hull and superstructure would certainly be worthwhile.
Esaiest method for a lightweight superstructure would probably be vacuum formed ABS plastic. We do not need a superscale superstructure on a rookie ship. Even better, vacuum forming is very easy, fast, and reproducable again and again. Can someone get me a some sort of superstructure drawing for the Emile and gearing? I'm still tossing around ideas for a lightweight composite cannon. I have a couple design ideas on paper, but not really happy with how much space they will take up. Sooo ... trying to think outside today's accepted cannon pratices for something light, strong, and reliable.
Webwookie, when I looked at the Lindberg Fletcher, I saw that each cross-section consisted of three lines, with a fillet in the corners. See diagram "A". The designers adjusted the shape of the hull by changing the width of the bottom line, the diameter of the fillets, and the height and angle of the sides. See diagram "C". The hull itself consisted of three distinct sections. In the amidships section, each rib had the same fillet diameter, and all they changed was the height of the sides and the width of the bottom. In the bow section, the bottom line was reduced to length zero, so that the entire bottom was round, and then the fillet diameters were reduced until they turned into a sharp edge at the very bow. See diagram "B". The aft section began where the keel starts to poke out and the hull starts to lift up. In the aft section, they adjusted the height and angle of the sides, the diameter of the fillets, and the width of the bottom to meet the shape they needed. See diagram "C". The end result was a simple, flat-bottomed boat that still looked "right". You can easily build almost the entire bottom of the boat with two pieces of 1/8" ply. Pretty good, huh? If a flat-bottomed boat is not entirely what you had in mind, you can actually split the bottom line of each rib into two pieces, and angle them like a really fat V, so that you get better water channeling as well as a closer match to the rounded bottom of the historical boat. See diagram "D". Does that give you an idea what to do?
For batteries, how many AH are you looking at? Reasonably priced AA NiMH's with tabs are 1.2V, 2.1AH. One could make a 6V 4.2AH pack of them for less than $20. Under $10 if you only need 2.1AH.
That definitely looks and sounds a lot like how I might go about doing it. I'm definitely not going to be making a dead-nuts pursuit of a +/-3mm or so accuracy model as what turned out with the Emilé Bertin. I'm thinking of going with a sort of modified baseboard construction (instead of the inverted followed by right-side up pseudo-keel construction of the Emilé Bertin) where the baseboard is flanked by very lightly angled, flat "slabs" leading up toward the point at which the hull becomes visible from the surface and the scale hull form takes over (with an extra hair of depth as permitted by the rules). Also, this is a hull that is definitely receiving bilge keels; without them, she could be more dangerous to herself than enemy merchant ships.
Good find on the batteries. I was looking at using a 5 cell, 6 volt, 3.2 Ah sub-c pack in my Mogador (pack weight of 11 ozs). But the Gearing is a lot smaller and only has around 3 lbs weight to play with, so Tug's pack would be the better choice. I know we are trying to keep the cost low, but a 2 cell, 7.4 volt, 2.1 Ah Lipoly pack is only around $30 and weighs about 4 ozs. Good for weight strapped tiny ships.
I was thinking of a heat-shrink-wrapped pack of 5 NiMH AAs in series with a Powerpole connector at one end. It'll weigh around 5.5 ounces including connector.
I like 7.2v. It's a pretty even number, and the battery packs come out looking nice. Remember, there is a possibility that 6v might not be enough. I think we should plan to save enough space and weight for a 9.6v AA pack, and if we find out that's not necessary then we can drop the number of cells and put the extra weight into ballast. I personally like the open-cell packs, using battery holders like you can find at radio shack. That way you can buy the batteries in bulk and save money, and you don't have heat-shrink tube or cardboard to trap water inside the pack. What do you think?
