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

[Builder2010]

I never saw that kit. Do you have any more information about it?

I printed the more robust ladder rungs and I’m pleased with the result.

This shot was taken during the removal process. I’ve found that using the flush cut tweezers thing that MicroMark sells seems to work pretty well in snipping tiny supports. I also used a very sharp #11 blade. The blade only works on parts that ARE NOT post-cured.

And here they all are ready to go under the UV lights for post-curing. In their native state, they were too flexible to be useful. That flexiblility is imparted by the Siraya Tenacious flexible resin in the mix. The extra girth really added survivability to these delicate parts.

I was at the local hobby shop and picked up the scale I-beams and some 5/32 angle stock to build the gun house.

I’m in a highly unusual situation. I am working five projects at the same time. I usually work one at a time, but not now. I have the turret project running concurrently with the Takom 1/35 AH-64D Apache. I thought I’d get the latter completed in time for my modeling club’s regional exibition, but probably won’t and will enter some of my previously built models instead.

Speaking of the show (in September), I slated to make two 45 minute presentations on the 16" turret project, the title of which is: “21st Century Modeling: Traditional Skills+3D CAD+3D Printing” That’s project #3.

Project #4 is creating a small n-gauge train layout for the window of the Newtown Hardware House in Newtown, PA. This commission job stems from my creation of an O’scale version of this iconic Newtown building that was a hardware store since its inception in 1869. The store’s owner was so impressed with the fidelity of the build that he asked if I could do the RR. I just happened to have built such a small layout with the grandsons 12 years ago and will modify this layout for the store. I’m making an n-gauge version of this model. At that size, I can 3D entire walls in one go, unlike this one where I had to have the walls laser cut.

Project #5 is helping a good friend and fabulous modeler, Chris Bowling, refurbish a 1:15 scale model of the NASA Space Shuttle. I’m tasked with creating the artwork for 1:15 scale vinyl wrap that will have the heat resistant tile design. I met Chris through our modeling club and his work is spectacular. We have sort of a mutual admiration society going. I’m not quite as festidious a modeler as Chris, but I experiment more and push the envelope. I’m sort of the R&D department. The model was originally built by North American Rockwell and will be on permanent display at a new air museum in Bowling Green, KY.

So if tend to drop out from one project or another, don’t worry, it’s just me doing what I do.

[Builder2010]

I got the gun drawing done so it’s about as good as I’m going to get it. I had Ryan take a look and he said it would work and was surprised to see it all naked.

With a decent drawing I was able to print it. The barrels are already printed. I had a choice to make of printing the entire gun assembly or print the shield separately. After attempting to install it in my mind, I didn’t like how it was going and printed it as a single piece. In actuallity, the shield assembly printed reasonably well. I chose to remove the trunnion pins and will machine them out of aluminum to the .147" diameter on my lathe. I drilled the holes a little deeper to accept them.

Notice the phos-bronze hydraulic lines to the rammer piston. My resin printed ones didn’t. It appeared that the pipes were not actually joined to their flanges in the drawing and they failed to form correctly. Better with metal anyway.

The trough that accepts the projectile and cartridge did not form. It was paved over with a resin sheet. Not sure where it was coming from. Drawing that trough was difficult for me, so instead of redrawing and reprinting, I used the Dremel with flexishaft and a spherical diamond-coated burr, and carved the channel back in. These will be partially obscured with a projectile and cartridge load. The back left edge of the curved shield was slightly missing, but was rebuit with Bondic.

Another view of the tail of the gun showing the trough. The trough and the sloped shelf next to it are brass on the rear gun to avoid any sparking.

The real test was how well the gun fit the slide and how well the slide fit the mounts. For the former, I had to open the gun opening much deeper. There was some errant resin growth inside. I tried using an appropriately-sized drill, but it wasn’t working well and I was afraid I would break something. I then turned to another diamond burr and ground it out. The diameter of the shield and front of the slide was perfect. The gun was a sliding fit.

As to the fit into the mount, it was perfect!

When painted these will look pretty good. I loved how the gear teeth formed on the elevation gear. Out of the four guns I printed (2 R and 2 L) one pair is good enough to use. I have some more metal works to add. A couple of the handles broke off on the side operating lever. I just thought of using some very thin shim brass to actually line the trough with real metal. I will experiment on one of the reject guns to see if that works.

So folks, WE HAVE GUNS!

I also finally decided to build the model exactly as it is in the ship. With the magazines correctly offset and in the correct deck, it will occupy a display space of about 1’ X 1’ X 1’ and that’s really not too big and much smaller than the 16" monster.

Next up will be to design and print the hydraulics and sighting gear that really complicates the turret. Then I’ll start working on the Ready Service Room and the projectile/cartridge hoists. I don’t have any good references on the structural steel that supports the hanging central column and the hoists attached to it. I did get a properly sized piece of brass tubing that will serve as the central column.

[surfsup]

Just Brilliant. What is next after this. Maybe the Bridge layout of a Capital Ship…??..Cheers Mark

[Builder2010]

Actually, I’ve been noodling the idea of making one of the four Iowa engine rooms. Could be impossible if techinical information is too hard to obtain. Would be intereseting as heck though. Model would probably come out to 20" square or so based on the fact that it extends across the entire internal beam. Much of the apraratus including turbines and reduction gearing would lend itself to 3D printing. The catwalks and stairs would benefit greatly from photo-etch, and I don’t have that capability (yet), and I also don’t have laser cutting (yet). Laser cutting is on my want list, with prices dropping and capability increasing with the solid state variety. One this at a time… let me get this one done first.

[Builder2010]

Hope everyone had a nice Labor Day weekend!

I machined the metal trunnions along with the seal for the trunnion bearings on the real thing. Simple turning operation. The pin size was .147" and I had to deepen the holes on the gun housings to give more meat in the junction. I made the pin’s depth is just about .200". I machined the first set using a collett for the 1/4" aluminum stock. The collett did not have a thru-hole, so I had to cut the stock fairly short so it wouldn’t extend too far out of the collett. I machined the trunnion pin diamter first and the inner surface of the seal. I then mounted the pin in a three-jaw chuck and finished the outside of the seal face. He I’m test fitting the gun frame onto the pin. My little Taig Lathe is in need of a new motor. The lathe is at least 30 years olds and the motor’s bearing are shot. There is about 1/4" end play and it’s vibrating like crazy. It’s amazing that it’s not destroying the cut quality, since the whole machine is vibrating together so the cutter and the stock are also vibrating together. It’s just very annoying. I can get a new motor from them for about $160.00.

I tried the finished part on the gun in the mount.

There are screws around the seals perimeter, but I’m not going that far.

Here are the four trunnion pins/seals. The two with the holes will accept the manual firing mechanism that feeds through the trunnion center so the gun can elevate without disturbing the mechanism. The manual firing mechanism is quite complex due to the interrupt system that prevents firing the gun when it’s pointing at any part of the ship. The gun is only firing mechanically when the entire firing system is out of commission. Normally the firing is electrical and remotely activated from the secondary plotting rooms.

I finished the metal hydraulic tubing on the guns. I removed the one I did last week. It was not the accurate and needed replacement. I also finished opening up the bore for insertion of the gun barrels and the cylindrical loading tray. The hand levers are breaking off due to all the pushing and shoving I’ve had to do to fit the guns. I will replace with metal.

I need to design more parts before I can go further.

[Builder2010]

Finished up with the guns for a while until painting and assembly. Added or fixed the broken levers and handles. I permanently glued the gun mounts to the frame. It’s okay to do that now since it makes a stable assembly for further work on all the ancillary equipment. I also got the rammer hydraulic lines in place and replaced the first long one with a more properly shaped one.

I cut out my gun house patterns, applied a light coat of MicroMark Pressure Sensitive Adhesive and stuck them onto a large piece of 0.040" styrene sheet. This represents about 2" in scale, close to the scale 2.5" armor on the gun house. Instead of using the right and left side gun house templates, I just cut one and used it to trace the other side. I then clamped them together and sanded their edges lightly so they identical. When possible, I used the corners and edges of the sheet for at least one of the sides.

Here’s a closer look at the gun house side…

All four of the top pieces had to be exactly the same width and the gun slots had to line up. So I used one of them to trace the other three, even though I had drawn them and they equal in the drawing. This eliminated the slight variations that would crop up depending on which side of the line I was cutting. I got most of them cut out today. I tried the sides onto the 3D printed curved back wall and was rewarded that the corner rabbett that I printed perfectly blended with the styrene sides. I don’t have any drawing stuck onto the side piece that I traced, but I will need the location of the side access hatch. For the actual hatch cuts I will trace the real one. I’m also going to located and drill all the holes for the foot rungs while it’s all in the flat. I have to do some finish sanding on the edges and the gun slots. I also have to sand bevels on the mating surfaces of the angle pieces so they mate properly. All joints will have 3/16" styrene angle as does the prototype.

Meanwhile, while printing parts for another project a calamity happened. After a major print failure… and I mean “major” in the sense that the only thing that printed on the build plate was the base raft. All the rest was a series of variously shaped blobs stuck to the FEP teflon film at the resin vat’s bottom.

I was able to remove the crap on the bottom without destroying the FEP (I hope), then I looked at the LCD protective plate and saw a series of bad cracks propagating across the LCD. I thought it was the tempered glass protective plate that I bought to protect the delicate LCD below. But when I removed the undamaged cover plate, I realized that the cracks were in the LCD itself. I did a light test and it failed miserably. Half the screen was disfunctional. The cracks are quite obvious in this image. I need to understand why the print failure happened in the first place. I’ve tried printing this part three times with not very good success before the complete mess that this attempt was.

I ordered a new screen from Amazon which will be delivered soon and I’ll install it on Monday and hopefully, all my projects will continue uninterrupted. Elegoo has a new machine out that uses a Texas Instruments DLP chip. This device has been around for a long time and since it projects its pixel image though lenses and mirrors to the resin vat and doesn’t get any physical pressure from the z-axis lead screw and stepper motor. It was the plate attempting to compress those hardening lumps on the vat’s bottom that caused the damage to the LCD screen. I think my next printer is going to that technology. So this summer I’ve added a new motherboard, new touch screen and now a new LCD screen. Wish me luck. I can continue to build the sheet work without the printer running, but I really need it.

I found out from Ryan today that the splinter deck is only 30" high, made up a massive series of square compartments with manholes separating each of them. I will only be showing a little bit of that detail. It’s only function is too isolate the magazines below from any shrapnal that may attempt to get there from action above. I don’t believe any of the Iowas saw any action that involved this structure.

[Builder2010]

I spent almost my whole day on the drawing board (well… virtual drawing board). I’m working on several fronts at the same time. Today’s work centered on figuring just what kind of cutaway will be needed to show the magazine buried three decks down, while showing some of the intervening spaces. It’s not easy and construction will also be a challenge. I also scoped out the wooden base and the plexiglass case. The base will require some lead time so I’ll have to get that constructed earlier than one might think. My last base was done by a dear old friend who lives in Albuquerque. He was the bass player in my band and an exceptional woodworker. I’m not sure I want to task him to build another. He’s in the process of scratch-building a stand up double bass. Just to clamp the skins requires 54 screw clamps which he just started constructing from scratch also. He’s just as passionate about what he does as I am. (or obsessed…depending who you ask.)

There will be lighting to illuminate the shadowed areas. There will aslo be compartments under gun ready service room. The main deck will be planked. There will be no furnishings on the intermediate decks. I think it’s pretty neat that V-Ray renders materials that are loaded from my older rendering engine, Podium. I renders much faster than Podium for these test runs.a

It’s one thing to cut openings in a SketchUp drawing. It’s quite another to cut them in styrene assemblies. In some cases the former is easier, but in others the latter is.

Before I could start gluing together the turret parts cut yesterday, I had to do a few more design steps. I wanted to cut the opennings for the side access hatches and telescopes while still in the flat. I also want to drill for the foot rungs. I also located the officer’s hatch on that small flat roof piece. I was able to cut one hatch opening and clean it up. The printed part fits nicely once I spent some time with needle files to finalize the shape. The hatch drops into the opening and the hinges sit on the surface. If I want to open one of these, I’ll have to reprint with a different hinge orientation.

BTW: In handling the hatch, the handhold broke off. I’m going to be replacing a lot of these with 0.020 wire.

Here’s a closer look at each.

The left side with the hatch out of the opening.

If I would have planned ahead a bit, I would have included these details in the patterns I used yesterday. 20/20 hindsight. “If my foresight was as good as my hindsight, I’d be better by a damn sight!”

Here’s the next pattern with the telescopes for the left side. The left side has two openings: the forward one is for the pointer’s position, and the rear for the sight checker. The sight checker uses that telescope mostly for training purposes to evaluate how well the pointer and trainer and managing their positions. I will be 3D printing the hoods for these telescopes. Their flanges go around the perimeter of these openings.

And here’s the officer’s hatch opening. I’m going to fabricate the counter-balance cylinder out of metal.

There’s one more series of parts that’s required in gun house construction; There are flat shield on each side of the curved gun shields that seal the curved surface from environmental incursions especially seawater. The curve of the shield covers the curved gun shield. There are two per gun side and then a bottom piece to tie it together. The upper edge is connected to the turret roof.

I used the gun shield in SketchUp in a sectioned drawing to capture both the curve size and position AND the interface with the roof. I can be pretty sure that this works since all the prints were produced from the same drawing. While there’s some minor size change in the printing process, it’s really insignificant.

Here’s an interesting shot of refitting the armor on a 5" turret when refitting the Iowa in the 1980s. Based on this picture, I need to slightly change the lower left corner of the telescope opening. It’s not a curve, it’s just an angular cut. In this image the guns (without barrels) are fully elevated. Really shows how the gun house fastenes to the main frame. Also good views of how the pointer’s machinery is fastened to the frame.

[Builder2010]

I’m giving Ryan a choice of how to display the innards of the gun house. My first approach would be a cutaway, but while not to difficult to execute, it doesn’t show all that much unless you turn it into Swiss Cheese. Ryan just texted me. It will be the cutaway version which follows the theme of the 16" project.

The second approach could mimic yesterday’s photo showing the entire armored casing in the air above the open gun house. This would show almost everything, but would have to be suspended above and it would raise the enclosure height. I could use acrylic rods to support. Lighting would require some visible cabling. In order to raise the casing, the guns need to be elevated, as they are in the photo.

The last is the most elegant and also the most challenging: making the forward parts of the gun house out of clear acrylic. I would leave the curved wall as it is. While I have clear resin, optically it wouldn’t be very good and not any value. Acrylic is very clear and shows no distortion. Gluing it together so it really clean is the first challenge. The second is cutting out the small parts with true and square edges.

So I’m also asking all of you. Which do you prefer?

I finished cutting out all the casing parts and trued up all the edges. I cut the telescope holes in the right and left sides, the ofc’s hatch opening, and the remaining access hatch opening. I clamped both angled face pieces together so I could finish shape the gun slots so they aligned perfectly.

To cut the telescope holes, I drilled a series of small holes through the drawing, and then used a larger drill to make nice rounded corners.

Here’s all the finished parts ready to be assembled.

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Since I don’t know which version Ryan will pick, I did some future planning… While all the casing parts were in the flat, and they’re all accurate, I clamped them to a nice piece of 0.080" acrylic that I had laying around and traced all these parts so I’m ready to cut them out if we go that way. If fact, regardless of Ryan’s choice I may cut out all those parts and see how well I can finish them. Having it clear would be pretty neat. You can barely see the scribed lines, but they’re there. Now that I know Ryan’s choice, I’m going to try and construct this version anyway since I’ve kind of wrecked that part of the acrylic with my scribed layout lines.

I also went at the back of the curved wall and removed that lump. I used a cutting disk to remove most of the stock and then my micro-power sander to finish. I may add some filler to hide all the tool marks.

With the acrylic in the wings, I can continue to construct the regular casing. I won’t do the cutaway until after it’s built if i go that route, so I won’t be getting too far out over my skis.

My new LCD panel arrives today and I’ve already stripped the old one out of the machine in anticipation. I hope it comes with a new under class plate since I cracked it a bit getting it out of it’s depression. It too is held with adhesive stirps. Should be running next week. It has to be running next week. It’s on the critical path of two major projects.

Y’all have a nice weekend!

[Russelle]

I think any of the options would look good, Myles

[Builder2010]

Just putting in a status report. I’m working on four other projects, one of which has a US Thanksgiving deadline so that’s getting all the attention. Meanwhile, I got more interesting images from Ryan that I need to keep designing. Still could use a few more, but this will suffice for the time being.

[Builder2010]

It’s been a while since I updated this post. I have been working on five projects at once; three of which are commission. This technically is one of the commission projects, although I’m not charging anything for it. When I last left you, I had to rebuild my 3D printer. I installed a new LCD panel which went well although more trouble than I thought. It’s printing well now. I also found out recently, when testing my exposure setting with a new test article (Starship from 3DRS) that I was under-exposing my resin by 20% since I got this machine more than a year and a half ago. When I initially calibrated it I used a simple flat calibration piece and derived 2.5s per layer. With this new part, 2.5s didn’t work. I printed a test from 2.1s to 3.1s by twos. 3.1 was it! It explained why I was getting such warpage and support breakage. When exposure is too short, the resin doesn’t have enough cure time to develop structural integrity. The warpage is due to the amount of hardening that still needed to take place in post-curing. And the support breakage (a resultant delamination) was due to the resin being too weak to perform.

During all this, I was designing the ventilation system that goes into the gun house. It’s a tricky design since the drawing is unscaled and undimensioned.

I had designed the overhead I-beams (wrong, I might add) and then Ryan came through with a passal of images showing the entire ceiling of the gun house (also good views of the ready service room and magazine). I have four beams. There are only two. I also had lateral beams. There are none. I also needed to know how the cross vent passed around the I-beams. They don’t pass, they go through. Makes sense since head room is so limited. I drew the assembly and decided to print it all in one go, I-beams included to ensure it all lines up. I did’t design the blower system yet as that will be a separate part to glue in.

This was the image that told me what’s what.

I placed my assembly into the gun house drawing and kept moving parts of it around until the ducting cleared the guns and nestled into the I-beam.

I scaled it .021, exported as an .STL file and loaded it into the slicer. My first setup used a 100% raft coverage area. The Tall aspect on that little raft started failing about 1/3 through the print. I could see it detaching from the build plate since the plate has risen enough to be clear of the resin level in the vat. I stopped the print knowing it would just be a waste of resin.

I redesigned the arrangement with a more substantial raft. I am having no problem with build plate adhesion and blamed the strange setup for the lost of attachment.

This will off the machine later tonight so I won’t know if it’s good until tomorrow. Once the ventilation is squared away, I’m going to dig into all the electro-hydraulics in the gun house, and then onto the ready reserve room below. With exposure change, I’m much more confident about fine details and small piping rendering nicely. I may reprint some of the more dubious parts I’ve produced so far. I haven’t glued or painted anything yet so it’s just time and some resin.

[Builder2010]

Just when I thought I had it nailed down last night, I tried the drawing again in the turret, and this time viewed it from a different angle and found this…

I had to re-configure the ducting that entered the handling space below. It had to clear the gun, all framing girders and enter the space through the center ring. What I came up with worked, but I have no idea how accurate it is. Ryan’s pics don’t show this particular duct. I also took the time to draw the blower system and set it up to print as a single assembly. The new printer settings are working perfectly and I had a lot of confidence that all of the parts would render.

The print is done and mostly cleaned up. I may still have some trouble with the upper outlet pipe. I may be interfering with the right gun’s curved shield space. Everything printed perfectly, nothing warped or broken and all the bolt heads showed up.

Now I just have to figure how to shoehorn this into the model during the build…

[Builder2010]

Work progresses…

I designed the Training Gear hydraulic plant. This sits down between the girders on the gun house’s right side behind the Trainer’s seat and regulator. Luckily this one is drawn in profile in one of the cross-section images I found so I could get the profiles down. I’ve scaled these drawings so they are representing correct lateral dimensions.

There are two output shafts that extend out of the end and I probably will make these out of correctly sized wire. It was gratified after finishing the drawing that it fit perfectly in the space it was supposed to. I have an add-on that facilitates making those neat curved edges. Also, SU is pretty easy to draw complicated pipe runs once you know what you’re doing with connecting lines and adding curves to them.

Here it is dropped into position.

Next up will be to design this units hydraulic counterpart, the Elevation Gear Hydraulic Plant.

As in the big gun’s turret, all the systems are driven by hydraulic motors with the pressure generated in a remote motor/pump setup. In the case of the big gun, the motor/pump (A-end) was physically remote from the hydraulic motor (B-end), but in the case of this smaller turret complex, the motor/pump was directly in line with it’s b-end hydraulic motor.

With my newly refined printer setup, I have no doubt that all that delicate piping will render. It should look pretty good.

[Builder2010]

The Elevation Pump/Motor Hydraulic System shares the same motor/gear box/reservoir with the Training System. The output end is completely different and the units are mirror-images of each other. But having successfully crafted the one, drawing the other went quickly. Both just came off the printer and, with the new exposure settings, the detail is exceptional and all the piping is intact and tough. I’m very happy with these results and it tells me that anything I can draw for this project with print as I want it.

I’m now wrestling with the human interface portion of these systems, the pointer’s and trainer’s regulators. These, like the rest of this job, are not easy to visualize or draw. All the pictures I have are persepective images and therefore, I can draw directly on them. There are very few surfaces that are parallel to the SketchUp axes, and many of the corners and junctions are rounded/curved. None of this makes it an easy SU drawing project, but I will persist. Ryan Syzmanski is enjoying seeing all these components separated from the complexity of the insides of the turret.

I’ll post the finished parts tomorrow.

[Builder2010]

Back to the ship.

My first prints of the elevation and training pump systems was okay, but a couple of details didn’t form and it bugged me. Here’s the first attempt.

You probably can’t find the errors, but I know they were there. I tried them on to see how they looked sitting in the framing. And they looked swell.

When I went back and evaluated the support scheme, I found that I misplaced the tiny support on the upper side of the detail, not the bottom-facing apex. This caused the detail to not form correctly until the build reached where the support was. This is support skills 101: the support goes at the bottom-most point what would start to form and create an island. There’s a moving line in the slicer that helps you identify this contact point. In this case, I missed it a bit.

When I repositioned the errant supports I got a really nice print. I also moved some supports or made them smaller where they were difficult to remove without damaging the model.

Those piping details are very, very fine. The phos-bronze wire is showing where the links are going to connect to the regulating pedestal. They will not be this long. I pre-“drilled” the holes in the drawing so I could easily open them up with a 0.032" drill.

The new setting is amazing. It’s like learning to 3D print all over again. I’m also reprinting the foot rungs since the new setting will make a truer and stronger part, plus a less warped base that I’m using as a drill jig.

[Builder2010]

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.

[Builder2010]

Just a quick progress report. I’ve spent over a week working on the elevating mechanism and still not done. Nothing about this one is easy to understand or easy to draw. What makes matters worse is the real ship, most of this stuff is buried in the front of the turret up against the lower portions of the armored front and you couldn’t get near it to make any real world measurements. I draw it in a separate file, at 100x full size. I then copy it, reduce it to 1:1 scale and export it to the master file. I then fit it to the gun stands and the shell sides. Nothing on the part is a right angles to the SU main axes. I have to figure where the parts need be separated for effective printing.

This is a view from the rear which is kind of what you’d see if you actually went into the turret.

All of this is created with images like this:

[Danie]

Can you imagine how hard it was to service those inaccessible bits?

[Builder2010]

Really inaccessible! Probably had to pull the shield off the whole mount to get to some of it.

This is what two weeks of drawing produces. This was probably the most complex SketchUp drawing task I’ve ever tackled. In addition to just the SU idiosyncracies, there was also the challenge of getting all the shafts and connectors to align in some reasonable fashion so they would resemble something that could actually exist in the real world. And then there was getting this stuff in such a way that it would successfully print. As a result, some of the operating pieces are touching other surfaces intentionally so as to add structural integrity to the printed object. I’m attempting to print as much of this mass in one piece as possible. Orginally I was going to use metal rods for the rods in the model, but with my printer improvements, I think the printer is up to job to print them all and make them relatively straight. We’ll see.

And the front view.

And how it’s going to go on the printer. Lots of corners and curves that needed specific supports. The flanks of some of the tiny bolt heads show up as needing supports, but I chose to not attempt it. The support removal would destroy the detail anyway so we’ll just see how it all turns out.

I’m going to put it on the printer tomorrow.

[Builder2010]

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.