5" 38 Mark 28 Twin Gun Secondary Battery from Iowa Class Battleships

[Builder 2010]

Thanks!

Work continues on designing the very complex (for me) Elevation Station. This assembly includes all the input controls, the output shafts, the optical telescope and its linkage, the elevation gear housing and the connecting shafts to the other gun and Sight Setters station. There are no right angles! Making it more complex is the coupling casting that ties the elevating regulator column to the gear housing. This thing. This, BTW, was not correct as drawn here.

The reason for all this confusion for me was none of my referece drawings showed the entire part, nor were there any that gave me a true understanding of its geometry. It took well over an hour to get this far. I even sent out the word for help from some other SketchUp, but didn't get a response. Here's what I had to go on.

I persisted and eventually landed on a shape that works and looks credible. Whether it's actually correct is a totally different question.

I then took this assembly with the beginnings of the gear housing and put it into position in the gun house on the master drawing. This is what I found.

The gear house (and associated shafting) was too low. I also found from a verticle perspective drawing of the turret interior, that the shafting an its associated apparatus were to far left. This is all the result of not having a single orthographic diagram of the equipment design or location. Some are perspective and others are isometric, but locating accuracy was very difficult to achieve. It just a series of aproximations.

I'm satisfied that I've got it right... enough... for now.

The Trainer's station is similar in design to this one and I'm going to use the same "casting" to join it to the other gun's elevating housing. There is another ambiguous part that I need to design. It sits on the gun side of the housing near the bottom and contains a ton of complexity of which I can make no sense. Problem is when I enlarge the drawings to bring out of the detials they disappear since the images were screen prints of scans of a manual and have no resolution when magnified. Again, it will be mostly quess work. I do have a picture of the Trainer's station with this component that shows more detail. I can cannabalize off that one.

 

[Wurger]

 

[N4521U]

Oooo yes, it Is a problem.......
Been my experience two solid objects cannot occupy the same space!
Doin a bitchin job tho!!!!!!

 

[Gnomey]

Great work so far!

 

[Builder 2010]

It was 11 days ago when I put this complex sighting system on the printer. Since then I did five different runs. Each had it share of problems from total failures when my build plate has lost its holding power, to failures due to mistakes in my design or drawing execution. Today I was able to get a fully usable part. I had to make some minor fixes using Bondic, but all in all it will do well. Meanwhile, I had designed and drew the Sight Setter's Regulator and incorporated it into the part's design and printed it as an integral unit. The Sight Setter's Regulator adjusts the two telescope prisms so they match the aiming data sent down by the gun directors. In normal operations all of these settings would directly operate the guns, but everything has a manual backup.

This is viewing from the turret front. The front armor shield normally hides all this, but I will cut it away so some of it will be visible. It's pretty cool in its complexity.

And the rear view that will be seen from the turret's interior.

After doing a trial fit I was rewarded with a pretty good result.

And the interior view.

While this was printing I designed the Fuze Setter's Regulator. This assembly is also connected to the front complexity, but is very close to the starboard side gun mount. I decided to print it as a separate part and will install it after installing the guns so I can get the trunnion cap in place. This device is used to translate the firing timing from the gun directors into the fuze setting system in the projectile hoist. It was mostly obsoleted when the proximity fuze was introduced later in WW2.

I've created masters for decals for all of these systems to simualate their dials.

I redesigned the acess doors with the hinges in the open position to show the insides and how the system were maintained. I also redesigned the optics hood with the open shutter so the shutter had more beef in the hinge so this fragile part had a good survival chance.

I'm now working on another complex unit, the projectile hoist. There are two of them, but they are not mirrored. They extend over two decks since they start in the Ready Service Room (RSR) before the gun house, pass through the center and end up in the gun house. I'm creating them this way. There are some structural steel cross-braces that support them. They do not go to the RSR's floor. They hang above it and the whole deal rotates with the turret. Unlike the big guns where the entire deck rotates to keep the hoist aligned with their respective guns, in the smaller 5" application, the hoist rotates, but the RSR is stationary.

It's very complicated to created curves on already curved surfaces in SU. You can't do the simple push-pull extrude operation because that only works when the two sides are parallel. To cut a curve into another curve, you have to created a negatively-shaped "cutter" and use it with an extension called BoolTools2, to remove the interferece area and create the shaped surface. You can also do this directly in SU with "Intersect Faces", but you have a lot of clean up work since it gives you the cutting line, but leaves an open space that you must hand draw all the interconnecting lines to create a closed solid.

While doing all this I finally finished that cute little n-gauge display layout that's going into the Newtown Hardware House in Newtown, PA. I was able to accurately model four Newtown buildings. These were drawn in SU using actual and Google Earth images.

I have the Trumpeter 1:32 F35b on layaway at Scale Reproductions, Inc. I was waiting for the most complex F35 to finally come out in 1:32. While I'm not a big Trumpeter fan, they're the only one making this model now, so I'm going to get it. It will be 2024 when I start it so stay tuned.

 

[Vic Balshaw]

 

[Wurger]

 

[PlasticHero]

Modelling by pushing electrons or scratchbuilding with a keyboard. When 3D printing was first gaining recognition in modeling, I had a somewhat negative view of it because it seemed "easy" and I knew nothing about it. This has as much depth of knowledge and skill as glueing plastic shapes together and sculpting with clay. I am truly and greatly impressed with what you are able to do.

 

[Gnomey]

Lovely work so far!

 

[N4521U]

Is there a good cheap Basic 3D program around?

 

[herman1rg]

Is there a good cheap Basic 3D program around?

For drawing or preparing for 3D printing?

 

[N4521U]

For drawing or preparing for 3D printing?

solids, for printing.
It's turning slowly into the norm.
I am in need of 3-4 1/72 British truck wheels for my trailer. Scales to 15-16mm in outside tyre diameter

 

[herman1rg]

solids, for printing.
It's turning slowly into the norm.
I am in need of 3-4 1/72 British truck wheels for my trailer. Scales to 15-16mm in outside tyre diameter

Fusion 360 is good

 

[herman1rg]

solids, for printing.
It's turning slowly into the norm.
I am in need of 3-4 1/72 British truck wheels for my trailer. Scales to 15-16mm in outside tyre diameter

Something like this can easily be resized in your slicing program FV 620 Alvis Stalwart Variants 2 by stephen67

or here Search Thingiverse - Thingiverse

 

[BertUS]

PlasticHero Please, keep in your mind that are a lot of moments will be there of absoluty madness when you waiting for 4 hours of printing and in the last 15 minutes you noticed a print-error like Builder describes. That moments I had never in the old days

Builder
really lovely work after a ton of patience.

 

[N4521U]

Fusion 360 is good

Well i did download it but now its telling me i need to upgrade my graphics card. Eh!
It's been about...... 10byears since I used Inventor so there's going to be a learning curve.... arrrgh

 

[Builder 2010]

You're never too old to learn new stuff. And, research seems to support that learning when old prevents some forms of dementia. I was 74 when I got into 3D printing and am now 78 and doing more complex things than I've ever attempted. The fact is when creating sratch-buit models that never existed before, being able to master the graphics and the printing is modeling making in the 21st century, Even after printing, you still have to get it all together and you have to paint and weather it all. Frankly, it's more model creation than opening a box of plastic sprues that someone else drew, engineered and molded so you can assemble it. I'm not being elitist. I love building plastic kits. I always alternate between scratch-build and kit build. It keeps me interested and not hung up. But I can be pretty sure that nobody in this world of over 7 billion people ever built an Iowa turret like I was able to do with this technology, and I'm just as sure that no one has ever built a 5" twin mount at this resolution either.

I found out that the fuze setter regulator that I modeled last week was an older version that was NOT on the Iowas. At first I thought, "Who's going to notice", but then my AMS took over and I had to draw and print a correct one. Ryan appreciates this. That's another benefit of this tech. If you don't like something, redraw and print it again.

It printed nicely. I also printed the opposite hand versions of the optics shields so I can pick either open or closed on both sides of the gun shield. And I printed some scale 5" projectiles. I'm going to need a bunch of these since they'll appear in the gun, the hoist the ready service room and the magazine.

Then it was full-steam ahead on the projectile and powder hoists. As complicated and confusing the sighting mechanisms were, this one is more so. Not only are they complicated beasts, but every illustration I have shows me something different. I sometime don't know if I'm looking at the same mod number. I know there are slight differences between the mount versions in lots of ways and these could differ as well. It's even confusing determining where the central tubular column sits. Is it in between the two projectile hoists, slightly behind them or equally located in the center between the projectile and powder hoists? I've asked Ryan to cast the deciding vote.

Even so, I'm a couple of days away from finalizing the projectile hoist part and will move on to the powder hoists. Regardless how the center column is situated, it appears that it provides support to all four hoists. In additon to getting the details and relationships nailed down, I constantly have to keep in mind how it's going to print and finally how am I going to get it all together. I found some actual diamond plate in the SketchUp 3D Warehouse that the artist has actually drawn the pattern in 3D so it can be printed. I'm going to attempt to print the hoists with the flooring in place in a single piece. I want to do it this way to ensure that it is all perfectly aligned. I test the part periodically in the slicer to make sure that it's all solid and will fit the printer as it gets bigger. I pay special attention to all those rods and connectors to make sure they're supported in various places (even if it dosen't conform perfectly to the prototype) and they're all perfectly contected to all the points and surfaces they're supposed to be.

Here's what it looks like now.
First, a screen print off of SketchUp: The tiny thing you see in the red square is the exact same object 10 smaller. That's actually real-world size. I'm drawing the object 10 enlarged to prevent any "small curve segments" that SU runs into. The entire drawing is saved as a component. Anything I add or modify on the big version duplicates instantly on the 1:1 version. I use the 1:1 version in the master drawing of the entire model, and it's the one that's exported to the scaled drawing where I reduce it again, by .021 to make it 1:48 scale for the printing and the actual model. By using it as a component I don't have to copy and scale it every time I want to use the 1:1 drawing. it's always there and up-to-date. It's so tiny that it's easy to lose it, so I put it on that big red square so I can easily find it.

And the same drawing rendered in V-Ray:

Still to do: The lower doors, and the power and hand-operation linkages. Part of the power system is drawn, but there's still more to do. I've made the center column hollow and will use it as a wire chase duplicating its real world purpose.

 

[Vic Balshaw]

 

[Wurger]

 

[N4521U]

It might be a while before I can draft a truck tyre with 360!!!!!!