Super modeling, Bravo !
Nice work!!
Very nice indeed, @mmarcovitch !
Work continues…
Rammer detailing is almost done. Got some great references for the cradle and spanning tray which will be up next
Got a good start on all the decking below the turret. Right now I’ve inadvertantly drawn down to the 2nd projectile flat. I may not go down that far. But here it is with the roller track in place. The turret and machinery spaces rotate with the turret and are supported by the rollers. The two projectile flats below them only have a rotating ring that moves with the turret so the projectile hoists would keep in line with their respective guns. The center column rotates which has the powder hoist chases. These go up the center column as clearly seen in this image from the Summerall Missouri Book.
The humans in the picture show the size of the ring gear. You can see the rollers under the tarpaulin. The powder hoist trunks are in the central column. The shell hoists are not installed in this picture. The heavy wedges lying against the walls are the clamps that go under the ring gear that prevents the turret from ever falling off the ship (as if that could happen).
Here’s what I’ve got so far. The shells are to scale. The gaps between the stationary and rotating parts is exaggerated in my version. I will adjust all this when actually building the model. The big parts will be made “old school” with styrene and acrylic sheet. I will print the tapered rollers though. The ring gear will go around the upper-inner perimeter. That will be printed in segments just like the real deal due to size limitations of my printer.
A lot of the round parts could be laser cut… either out of clear acrylic or MDF. I have access to U 0f L’s Maker’s space and they have terrific laser cutters for public use. It’s been closed due to the latest COVID surge, but that will end and I’ll be taking advantage of it for this and other projects in the works.
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I need some more help. I’m trying to use Flowify. I used it a couple of years ago, reviewed the video just a few moments ago, but I’m getting an error and, frankly, not even sure what it’s talking about.
It’s the projectile cradle that catches the 16" projectile as it comes up the elevator, then rotates it so it can be rammed into the gun. It has a waffle pattern on the bottom which I’m trying to re-create. I’m also attaching the file.
Cradle-Spanning Tray.skp.skp (700.7 KB)
Have you tried the sketchUcation forums? Flowify questions seem to get decent help over there.
https://sketchucation.com/forums/viewtopic.php?f=323&t=61363
Also, if that’s just a cylinder shape, maybe you could do it with True Bend?
Thanks guys! Truebend did the trick. Took me a half hour to finally figure out that it was only responding to the red axis and that I had to change axis orientation on the group to get it to bend in the direction I needed. I watched three videos. It was the last one where my lights finally turned on. I still did the job with too many faces, but it’s going to print at such a small scale none of that will matter.
I’ll figure out Flowify too, but I don’t need it now. Achim’s Razor!!!
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Drawing continues feverishly. I finished detailing the major components of the gun loading system in the gun house itself. This includes the rammer machinery which exists in the officers’ compartment at the rear and the cradle and spaning tray. The latter captures the 16" projectile coming up from the projectile hoist, rotates it to the loading angle of 5°, and with the cradle and spanning tray provides a smooth surface to slide the projectile and the 6 powder bags that follow into the gun’s receiver.
Drawing the cradle involved all of my SU skills and a new extension, “Truebend”. TrueBend enabled me to wrap the rib pattern around the barrels of the cradle and spanning tray. There were a lot of mechanical relationships that had to be figured so the cradle would fold in the proper way. At 1/72, I’ll be lucky if it prints at all let alone actually articulate, but I wanted it to be mechanically accurate.
This is the loading position. Remember: there will be bulkheads on all sides of the guns separating them from each other and the officers’ space. The rammer machinery is outside of the gun chamber with the rammer chain going through the wall.
Here’s the firing position.
The singluarly most difficult part of this whole part of the project was figuring out just what was happening with the spanning tray control link and how it attaches to the tray. I had one picture on which to rely and it was ambiguous. My first attempt was completely wrong. The arm had to be far enough away from the unit to clear the main pivot bearing, but I couldn’t quite understand just what was happening.
The part in question is the light color shape next to the gun captain’s elbow. It looks like it’s sticking straight out from the tray, but its actually first dropping down and then projecting outward. Because the tray is angled in the process of flattening out, you’re looking as much at its end as it’s top. The big hinge is at the bottom of the spanning tray. Because of all this angularity and perspective I wasn’t able to trace the shape as I do with other objects.
Here’s a view of what I drew. It’s still not perfect, but I’m not sure how to make it better with just his one image.
The real question I have is just what will print successfully at 1/72nd? A lot of the details I’ve drawn may not reproduce such as the hex-headed bolts.
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I’ve finished the detailing of the gun loading equipment and started working on the bulkheads and other machinery in the gun house itself. I was able to do a pretty close job on the powder doors after finding another good diagram. Here’s some status shots. Remember, the turret walls will be from the kit.
And a rendering of same…
(upload://olxX1SN9zEwUzvpNOXjWl3TCWDc.jpeg)
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More progress on Missouri Turret interior.
Working on the pan deck after detailing the ofc’s compartment bulkhead. I have to constantly remind myself that the ultimate model will be 1:72. That means the entire bulkhead is only a little over 5" wide. That’s small, but there’s a bright side; I can print the entire bulkhead in one piece. I’ve delineated the elevating gear and am thinking about how to make the guns movable, but that may not be necessary since the model is going to be under cover. I still have some geometry issues. For example: the port side guns shield is hitting the wall of the Pan Deck. I don’t want to move the guns so I may have to make the pan deck slightly larger in diameter. There are some errors that need correcting like the lack of thickness of the pan deck floor. It should be as thick as the lip rising up from the Breech Clearance Pan at the bottom.
The guns elevator by way of a large lead screw surrounded by a hydraulically driven rotating nut. The gun turret traverses by another hydraulically operated motor turning huge pinion gear engaged with a ring gear that surrounds the entire pan deck. I’ve yet to draw either gear and many need help drawing the ring gear. There are two pinions sets driving rotation. All of this hydraulic stuff is there so there’s no chance for an electrical spark anywhere near the gun floor. The pumps and electric motors providing the hydraulic impetus is one deck below on the electric deck. That’s the next drawing challenge.
There’s the giant optical rangefinder and the manual aiming stations that need creating in the gun house.
Still have a lot of drawing to do and still waiting for the kit and metal gun barrels to arrive at the hobby shop.
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Beautiful detail, I love it.
But you would KNOW that it is articulated! 
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I’m still waiting for the darn kit and guns to arrive at the hobby shop. It could be built without the kit at this point since I’m detailing so much of the stuff the kit has as well as all the stuff that isn’t. Earlier this week I got the lead screw elevating gear drawn. I found a good lead screw on the SketchUp 3D Warehouse and elarged it to be battleship-sized.
Today I finished up the traversing gear. This includes the B-end motor and gear boxes on the pan deck and the action ring and pinion gears protruding from the electric deck. My pinion and gear set has bigger teeth since it has to be able print in 1:72. And just for fun I figured out how to make rifling in the big guns.
Next up is a massive amount of equipment on the electric deck and finishing up the detailing the main gun houses. Interestingly, there was a manned station on the electric deck with a hand wheel a la those found on 40mm quad emplacements. These were manual stations to elevate the guns. There were three stations, one for each barrel. In the recent video “Raising the Iowa’s Guns”, the mechanics were using pipe wrenches on the shaft that goes to a bevel gear in the coupling between the elevating nut housing and the hydraulic motor. It was very slow going, but one deck below is the station with hand wheels to crank the guns up and down when the hydraulics were unavailable. It had to be a rough job to hold, sitting in a compartment with a load of electro/hydraulic machinery running and basically doing nothing unless something is not working.
The vertical tubes coming up from the deck (one straight, two curved) are the projectile hoist chases coming up from the projectile flats. The hoists are arrayed around a circular moving deck, but the three projectile cradles are in a straight line in the gun house, which is why the outer two have the curve.
Here’s a view from below show the traverse pinions. As I said, mine are a bigger diameter and larger tooth design than the prototypes. The teeth at the scale the model will be are too small for successful printing and eventual use. It thought drawing the gears would be difficult, especially the ring gear. I have a SU externsion to draw volute gears. To draw the ring gear I drew and external gear of the same diameter as I wanted and used it to “cut” the ring teeth by using the INTERSECT FACES selection to embed the teeth shapes into the ring gear blank. I then pulled it to the thickness I needed. I used the same pitch size for the pinion gears. I had to experiment to get the right diameter to mesh correctly.
And using the same technique I was able to create the rifling. This time, I used the actual rifling count (96) to create a ring gear, pulled it to make it deeper and then added the twist. Was really easy.
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Twist by rotating one end? I would think that approach will yield a reduced diameter in the middle of the barrel. If so, perhaps that is inconsequential for the purpose at hand.
Probably did, doesn’t matter. Barrels are not going to have rifling at that scale AND I’m using commercially turned metal barrels sold by the same company who produces the exterior kit… Takom.
The rifling did reduce the diameter in the center slightly… Good pickup! Doesn’t matter since in the scale rifling wouldn’t work.
Thanks to all. I got some more images of the floor area in the officer’s compartment. It turns out that the reason it was ambiguous (to me) was the flooring plates are removable so they can get to the buried ramming machinery. It was the buried rammers that didn’t make any sense to me. The floor is supported on some legs and trusses. It’s pretty deep and it has four steps to get to the operating level. Here’s how I interpret it.
While there is more and more wiring and piping that can be added, I have to keep in mind that we’re printing in 1:72. If it was 1:48 or 1:35, it would be a whole different deal.
Onward and upward.
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I just spent two days building the support system for the massive range finder tube. My first attempts where what my mind’s eye “Thought” was the shape of the parts. I was completely off! I erased it all and went at it again. This time it’s pretty close. Having no real-world measurements or working drawings with dimension, the whole deal is a giant SWAG (simple wild ass guess). The support system is much more complex than I originally envisioned.
All the rolling surface are bronze or brass.
I’m getting pretty good at drawing sector and pinion gears. The gear teeth on the prototype are probably half the size and twice the tooth count, but I’m always thinking about what will reproduce in 1/72 on my 3D printer. I’m thinking of printing the enitre range finder in two parts mating in the center. All depends on how I can support the parts in the machine.
There’s still more to do on this part. I have to put in the three operating stations with their handwheels and optical sights. There needs to be a way to operate that pinion also. And then there’s the outer ends with the optics, weather seal and outer gates and their controls.
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What your accomplishing is simply mind boggling ! Bravo ! 
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Thanks! To boggle minds of people on the SU forum is a heck of a compliment. It’s like rigging a model sailing ship. You just do one thing at a time and not look at all the rest. When I’m done it boggles my mind too.
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Continued design and have the range finder complete except the weather seals at the wall openings. These weather seals are a soft barrier that’s going to be pleated. It transitions from the rectangular opening in the turret wall to a round shape around the RF tube. This is a very hard shape to model in SketchUp. I’m thinking to shape it out of Sculpey or Milliput and then model a flexible latex shape over it.
Here’s the complete rangefinder. The operators’ seats are going to be very small in 1:72, so we’ll see how they print. I may have to eliminate the spindles holding up the back. Again, not having a true perspective of all the details on the RF so the distance and spacing is all guess work.
I’m about ready to do the Electric Deck and the manual aiming stations on the turret level. That’s going to be fun since I have no actual pictures of this apparatus. I’m in the process of scheduling my more comprehensive visit to the USS New Jersey accompanied by the Curator in early May. I don’t want to start printing anything until I have final sizing complete. That said, I probably can start printing the guns themselves once I have the model in hand. I’m thinking about laser cutting some of the acrylic walls, and may be able to do this myself at the University of Louisville’s Makery. We’ll see.I thought about selling these parts. He thinks there’s a market for it. I said I see how the printing goes before deciding on commercializing anything.
As I’m writing this, I did pick up the model, but not the guns. I may use the kit’s 2-part plastic ones. My hobby shop owner didn’t know how to get the metal ones. Having the model in my hands enables me to get some actual measurements directly and modify the drawings as needed. My LHS owner asked if The model and guns arrived at Scale Reproductions and I’m picking it all up today.
I also thinking, based on another suggestion by Marty (the plastics manager at the LHS) to installed acrylic windows in the skin instead of making an entire face out of clear stuff. The model has the entire house exterior as a single part! That makes it a bit more difficult to make entire faces out of clear acrylic.
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