5"38 Cutaway Turret Complex; CAD and 3D Printed

Impressive as ever …

Thans you!

While watching a very boring Superbowl game I worked out where the the cutaways would go. I also played around with using Vray rendering with the interior lighting, but I have a lot to learn about this product.

Look closely at this one and you can see the rifling in the gun barrels. The curved gun arc shiels are not in these drawings, but are on the actual model.

The lighting power I was using with Vray wasn’t enough. The LEDs I’m really using will be much brighter. I will be creating parterns from these drawings to accurately make the cutaways without damaging anything… or at least that’s the plan.

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After flattening the drawing of the cutaway areas in SketchUp, I moved screen prints of the individual cut faces and imported them into CorelDraw. I then combined them in the configuration resembling a box unfolded and printed it out.

I tack glued this page to heavier stock paper abd cut the opening so I could trace the pattern onto the model.

I added some pressure sensitive adhesive to the pattern to help hold it to the model for tracing, but it really didn’t do so well. I just held it in place during the trace. I had to pay attention to the lighting in the rear and be particularly careful around the ladder rungs runner up the side.

The above took place on Monday.

Today, I loaded a carbide router in the Dremel and went at the model. This was one of those scary kinds of modeling tasks where a false move could be a ton of rework. Since it’s a complete scratch build I do have the ability to re-create all the parts, but I don’t want to.

Before doing the cutting I mounted the rear lighting in place with the 3M Transfer Tape. Cutting went well. Actually, better than I expected.

The cuts, of course, were a bit ragged. I then used the Dremel with a diamond burr to refine the contours, and finally, files, sanding sticks, and my Micro-Mark power sander to clean them up further.

A lot of the roof is now Swiss Cheese and finding purchase for the front ceiling lights is now more of a challenge than I anticpated.

I needed to make some relief cuts on the roof beams where they cross over the rear lighting system. It’s a bit rough, but it’s the upper side and will not be visible.

I’m just about ready to prime this stuff. Today would have been a perfect day; 60 degrees, sunny and no wind, but alas, I’m not ready for that. The hobby shop has a spray booth in the back work room which I have access to. I may use that if the weather is not cooperating. Primer painting is on the critical path and I’m getting to the point where it will stop work if I don’t get it done.

You’ll notice that I whacked a couple more ladder rungs in all the rough handling during today’s session. Not to worry, I have another dozen or so printed and ready for installation. Drill out the old and install the new. Can’t do that with a kit. You break critical parts and you have to get customer service on the line to get a replacement.

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Jeez Myles, this has been breathtaking stuff throughout but now it’s positively buttock-clenching with all that ventilating. An exceptional project.

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If all else fails… You have nailed the battle damage on the turret :+1::grin:

Seriously, … Very nice work on the cutaways

Amazing! I can’t fathom how long it takes you to CAD those parts…
Speaking of CADing, do you have any place that you recommend to learn from? I’d like to get into it at some point, but don’t know where to start.

With SketchUp, there are a lot of free videos to get you started. I like SU since it doesn’t have a lot of parametric decisions you need to make before you make shapes. That said, you can still dial in specific measures, distances and angles at any time in the dialog box at the bottom right of the work surface. Out of the box SU is reasonably flexible. When you add the myriad of add-ons (most for free) it becomes a real power house. Like playing guitar, to get started is easy. To master it takes years. I have Meshmixer, Blender, and other packages loaded on my computer, but have used SU for so many years, changing is hard. SU is primarily architectural in nature. To do machine parts with lots of internal and external curves, Fusion 360 may be a better choice. If I was learning from scratch I might go that route. I hit shorcut keys so fast, it’s like touch typing. I don’t conciously think about it. It’s all auto-pilot. Like finding the brake pedal on the car when driving.

In a short session today I got the light installed in the front of the gun house roof. That gives three relatively bright LEDs in a small area, so I think I have enough light there.

Running out of time, I just put the GH together to see how it will fit together. I had to remove a bit of the roof girders at the rear where they impinged on the raised rib that supports the rear, semi-circular roof piece. This assembly is so critical I need to take my time. I’m going to use the Gorilla construction adhesive so I’ll have some working time to get everything in perfect alignment.

It fits together okay and will glue up as expected. I replaced the broken ladder rungs and broke two more 0.020" carbide drills in the process. These holes are getting expensive. I bought re-sharpened drills this time since they’re cheaper, but they seem to break more readily so the reduced price may not be meaningful in the long run.

And I finally decidehd how to get the gun house together. There were two problems. The sight telescopes stick out and prevent the walls from sliding down into position. And the guns! In the 1:1 world, they fully elevate the guns and drop the entire shield over top. I suspect that the telescopes aren’t even installed yet. In my case, the guns are going to be fixed at 0º elevation. Getting the gun house over the level guns would be difficult if not impossible.

Answer: Clip the telescopes at the position at the edge of the base, glue the outer portion into the blisters. You will have difficulty seeing the joint between the two parts. They’re a little long anyway and the cut can remove some of the excess length.

As for the guns, I’m going to insert them into the slides after assembly just like they do in the 1:1 world when they have to replace the barrels. Incidentally, the barrels are held with a step thread joint with a retaining bolt, so they can be removed at sea with just a half turn. I had to further reduce the slide end diameter so they will slide in easily and not cause any damage by using excessive pressure. They will be painted and may have bare metal foil on the slide area that adds some thickness.

I got a communication today from the USS New Jersey Museum that the ship will be moved to the Philadelphia Navy Yard dry dock on March 26. Bottom refurbishment will be complete some time in May. Visitors will not be allowed on board during repairs due to none of the safey systems being active. That means my deadline is now in May or later. That’s actually good. I’ve got a lot to do and rushing never works. I have other projects in the wings too, so I will be busy.

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Back to the manger she was born in …