Wonderful progress 
Thanks Tuna! That’s progress if you call “one step forward and two steps backwards”… progress.
Yesterday (Friday) was somewhat frustrating! The weather was good for painting and I really wanted to get everthing I could primed. I had to do some mods first. The projectile hoists didn’t match the wall height of the projectile flat core. I had originally drawn these to match the shorter height, but I changed that last week when I found that the two decks were different heights. So I reprinted both of them to the higher wall height making the projectile hoists now too short.
So I used the surface gauge and laid out a cutting line to make the walls the same as the hoists. All good? Well… maybe not as good as it should be. Here’s the new wall height.
And here’s the stack showing the nice tight fit.
Then I found out why the two walls were different heights in the first place. Due to the large boss hanging down from the electric deck, the upper projectile flat wall height was shorter than the lower projectile’s deck. In other words, I had forgotten that I had alredy accounted for this difference when printing them originally. The two walls were intentionally different. So now the lower deck’s hoists fit perfectly as shown above, but the upper hoists are anout 1/8" too short. I really don’t want to print another deck, nor do I want to mess with the drawing and print another set of three hoists. They were tough enough to get right the first time. I think I’m just going to scratch build some spacers to close the gap.
The next frustration kept occurring as I was adding pieces to the painting board. Some of the components, which I thought were fully done, were “almost fully done” and required some additional cleanup. One of the rear compartment prints had the spanning tray break off…AGAIN! This piece had a very thin weak spot as the tray joins into the cradle at the faux hinge. I’ve had to reinforce them with Bondic. It’s that point that broke. I had to sand off the old Bondic and re-attach the piece. So this all took longer than I wanted. I was short on time. I had a physically therapy appointment at 4:00 to work on my sciatica.
I did finally get all the masking done of the projectile decks including the three spots on each where the hoists will be glued.
With that, all the big parts (except the rear bulkhead and the gun girder) are ready for primer. Masking the electric deck took a bit of time also.
Here are all the rest of the parts ready for paint. I masked the gun recoil slide area which remains as natural metal. I’m using the gun barrels as a convenient handle to paint the slide/yoke assm.
And the rest,
Besides the aforementioned gun slide, rear bulkhead, there are still a ton of even smaller parts that I’m not going to prime. Many will be painted when they’re glued into their final locations.
The last frustration that kept me from painting was finding out that one of my LEDs illuminating the powder flat was sitting where the double powder trunk was going.
This is why!
And here’s the fix. Re-rounting the copper foil tape to the rear. And as I’m looking at this image, I see that the other LED is also where the single trunk’s going, so I have to move that too. Ugh! I don’t know why soldering the LEDs over the styrene patch didn’t clue me into the fact that the powder trunks went there. It just seemed like a good place to put the lights. Ran out of time before installing the LED. When I repair the tape, I no longer rely just on the tape’s adhesive. I add solder to ensure a good electrical connection.
I have to keep reminding myself, “Scratchbuilding is fun! Scratch-building is fun!” Whenever I complain to my wife, she reminds me, “It’s your hobby, no one is telling you to do it!” She is very unsympathetic.
Weather permitting, on Monday I’ll have the LEDs re-routed, the spacers fitted on Projectile Flat #1 and get some primer put on. I’ll also have the gun girder and back bulkhead ready for paint also.
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Happy Monday. The weather was PERFECT for outdoor painting. I took all the major and medium parts outside and used what was left of a can of Tamiya gray primer for the gun barrels, a full can of Tamiya white primer and then some Rust-oleum flat white for what was left after I ran out of the Tamiya white. I just plop all the parts on the boards to which they were stuck using rolled blue masking tape onto another big piece of cardboard and that onto the top of our two trash totes. There was just a slight breeze and I wore my full 3M chemical vapor mask since there was lots of spray around. I even took off my Apple Watch and put it in my pocket so it didn’t get hit.
The big parts had their bottoms painted too. When the upper paint was dry enough to turn over, I sprayed all their bottoms. The LEDs were masked with the Molotow Liquid Mask.
The Rust-oleum needed 20 minutes to dry to the touch. I used the time to do the lighting scheme for the turret gun house. This time, instead of soldering over styrene, I made a laminate using some 1/64 aircraft ply. The wood will withstand the soldering temp much better than the styrene will. I use Eutectic Solder which has the lowest melting point of tin/lead solders. It has the same freezing and melting point with no transition zone. It is 63% tin and 37% lead and melts at 183°C (361°F). Having instant-solid transition eliminates the opportunity for a “cold” solder joint. Cold joints occur with other solder blends when the joint is moved during the time when it is slushy (neither liquid or solid). The crystaline structure that forms is non-conductive and ruins electrical conductivity. It’s slightly more expensive, but it’s worth it.
Again, I used Bondic to make instant wire clamps. I again used the 3M transfer tape to hold the front and back light assemblies into the plastic shell. This will all be painted white like the other walls.
I’m thinking about scratch-building the last bit of wall detail that goes on the back wall of the gun house. These are basically a bunch of wiring and junction boxes.
So here are all the pieces back in the drying solid before the detail painting begins.
As an aside, the exercise program I’m working on along with the TENS 7000 that I bought from Amazon appears to be working. It’s making the sciatica much better. The TENS unit stands for Trans Epidermal Neural Stimulation and uses high frequency electrical waves to quiet the nerves down that are generating most of the pain signals.
Tomorrow, I will begin some detail painting. I also have to bite the bullet and start working on the final pieces of the puzzle: the outer barbette and outer shells of the lower decks.
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Very short session today, and I woke up thinking about how to make the outer cylinders and the barbette. I decided to hold off in detail painting until I get further along with these outer barrels. Reason? There are some critical fits to the inner structures and the round outer decking that must bridge the gaps between the inner and our barrels. I don’t want fancy paint and detail parts in the way as I massage all this stuff to fit. And massage i definitely will have to do if past experience is a prolog to future experience.
I already printed out the patterns for these cylindrical shapes. This one is the biggest. It is the outer shell for both the powder flat and the lowest projectile flat. It is also cut on a bias at the bottom where the entire stucture is welded into the ship’s framing. Only on turret #1 is this angle cut made as the ship is already narrowing at this point. There are no powder magazines flanking #1 turret because of this narrowness. The other two turrets have some room between the turret cylinders and the ship’s armor belts.
Here’s Jim Slade’s rendition of this barrel (straight and tapered portions) that he created from the actual ship’s drawings. The fingered extensions at the cut off portion are the weld points to tie the turret into the ship’s structure. Notice that this is where the roller bearing and gear rack gets mounted. I hope to be able to do mine this way also. Ttuhat hatchway is the only opening into the turret other than the entrance under the rear of the gun house.
As before, I stick the pattern onto the 0.040" styrene with the MicroMark Pressure Sensitive Adhesive, just lightly applied to the edges. I then scribe with a #11 blade and then snap it aprart.
Here’s all the parts for this barrel. The circle will serve two functions. It will be the former to mold the sheet into a drum, and it will provide the stock for the annular decking that is around all three lower decks: powder flat and the two projectile flats.
The odd shaped pieces will be the angled flats that get glued in after the cylinder is formed.
My challenge is three fold. I have to get that stiff 0.040" styrene into a cylinder with the ends matched and glued so it won’t pull apart. I aslo have to glue in the annular decks which will reinforce the cylinders, and lastly, I have cut the entire cylinder assemblies in half since I’m planning on doing it as a clamshell.
That splitting into clamshells is a huge question mark for me. It has some unique value in showing what’s going on in that annular ring, e.g., the air bottles and the powder scuttles. But it will be very challenging to get the cuts done AND STILL have the halves maintain their cylindrical profile. I’m rethinking this idea and will maybe revert to cutting away some of the cylinders in strategic locations while still preserving their structural integrity.
First things first. I’ve got to form the cylinders and glue them in such a way to keep them together before any cutting.
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Got some suggestions for making that flat styrene round; using a rolling pin or heating in the oven. I was not going to attempt the oven. I’ve had bad experiences with heating styrene to bend it. It quickly goes from soft to a mess. I did try using a rolling pin over a soft substrate. Did not create any curvature at all. Ended up doing it the hard way.
First I needed to stabilize the various rings so I could get a test fit on the wrapper. I have a pile of 3/8" threaded rod left over from the Sikorsky S-38 restoration. I cut another annular ring and put them together on the threaded rod with some big fender washers. I immediately ran into dificulty with the 0.040" disc thickness. It was flexing all over the place and made wrapping thes sheet very difficult.
Regardless, I was able to test the wrapper fit and it was the right length. I actually figured out the disc diameter by dividing the wrapper length by Pi. That number still works! Using tape and rubber bands I got it to stabilize long enough to take a picture.
I added a splice plate on the squared ends of the wrap and glued it old school… I mean really old school using Testor’s tube cement. I find this standby adhesive works well when you’re gluing large surface areas. Liquid cements seem to evaporate too fast to get a good adhesion. Clamps insured that the joint stayed together during curing.
Because of the thinner sections where the cutouts are, the cylinder wants to turn into an oblate spheroid (football) shape, but the rings will force it to round out eventually.
While this was curing I got to work on the annual discs opening up the inside to create the actual ring shape. To establish the i.d., I first tried to trace the o.d. of the powder flat’s lower edge, but the accuracy of this method was dubious. The ring needs to fit quite tightly.
Next attempt, I used the caliper to measure the diamter, split it in half and used a dividers to scribe an accurate circle. This worked well and after a tiny bit of shaving with a #11 blade, got an almost perfect fit. It was originally too tight and caused the thing ring to fold over.
After taking off the clamps and trying on the drum, I found that the 0.040" styrene ring didn’t have the structural integrity to withstand the drum’s springiness and it was distorting all over the place. Ergo, I can’t use this thin stock for the annular rings. I’m transitioning to 1/8" Masonite which is much, much stiffer. The extra thickness shouldn’t detract from the model. It will also provide enough lateral strength to retain the drum’s shape when (or if) I decide to split the hemispheres for the clamshells.
I was originally going to use this piece of Masonite scrap, but I found some better pieces floating around the shop. The lowest ring has the cutouts and this piece will work for that one. Waste not want not… The only trouble with Masonite is the porosity of the cut edges. I have acrylic sanding sealer that, when applied in several coats, gives the edges a finished look.
Tomorrow’s a physical therapy day again which will cut into work time.
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Naturally, don’t we all? 
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Of course! Everyone should have a stash of 3//8" threaded rod. Here’s where that stuff was used. This was a solid bronze large model that was on display at Bowman air field in Louisville since 1939. It got completely wrecked over the years and I was commissioned to bring it back to life. It took months and a lot of significant fussing, but it was restored. The rods were used to support this very heavy model in correct positions and aligned so I could solder it back together.
Onto today’s progress.
PLAN A: 0.040" thick annular ring. Failed due to too much flexibility
PLAN B: Cut annular rings out of 1/8" Masonite… nice and stiff, but a pain to cut and finish
PLAN C: Idea given by Dioramartin on Kit Forums to make the thin rings strong by using Evergreen structural shapes. Three times a charm. I have made many scratch-built items using Evergreen structural shapes and I should have thought of it. But… who cares. You take good ideas from where they come.
Using 1/4" Evergreen I-beam stock I cut a series of peices to stiffen the annular ring and then glued another ring on top of this making a completely stiff assembly.
I used a piece I was going to scrap for the bottom web leaving the perfectly fitting one as the top visible ring.
This was pretty cool since the 1/4" thickness put the ring’s top level almost in perfect line with the floor level of the powder flat interior. Happy coincidence.
But there’s a wrinkle! Two parts of the this ring have to be chopped off due to the truncated aspect of the #1 turret’s lower end. This cut removes a significant part of the ring’s inner structure and destroys some of its structural integrity.
To resolve this dilemma I added some more interal structure. This helped a bit.
After making the cut, you can see there’s not much left of the old lateral I-beam.
An added web of 0.040" styrene restored some of the strength. I still had shape the web a bit to get it conform to the rings circumference.
The true test of all this work was putting the skin on it and seeing if it held shape. It did what it’s supposed to do. When the other rings are in place the oblate shape will round out nicely.
Here’s a side view of this assembly.
And here was a test with the truncated wall. Clearly, it will take a bit of finessing these flat walls to get them tight, but I have no doubt that it will look okay.
Getting this drum formed and solving the annular ring problem was huge for me. I really was concerned about this aspect of the build. I have to make two more ring sets for each projectile flat, but having a viable method takes all the angst away. I’ve left the settings on my two Starrett machinists dividers from the final ring i.d and o.d sizing so I’m certain that the additional rings will be exactly the same size, therefore guaranteeing that the drum will be perfectly cylindrical from top to bottom.
I also realized today that I did NOT make templates for the barbette portion of the outer drums. That and the extra material being consumed in making the additional annular rings created a stock shortage. I put an order for two more 12" X 24" sheets of 0.040" Evergreen Styrene. I ordered it from my wonderful local hobby shop, Scale Reproductions, Inc., even though he doesn’t stock these larger sheets. I have a goal in flife to keep them in business. The model building community in Louisville, KY is alive and well.
Due to the strength and stability of the constructed rings, I feel more confident that I could go with the clamshell scheme.
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Worked on the second set of annular rings today, with a break to go to the hobby shop to pick up more 0.040" large sheet styrene. When he special ordered the large sheets for me months ago, he ordered more than I needed. He still had it and I bought more.
I measured the rings for the projectile flat, cut it all out and found that my i.d. was about 1/32" too big and wouldn’t work. That’s part of the reason why I was running out of my original stock. I remeasured and re-scribed. For the first of the two rings, I scribed the circumferences and then made radial scribes to faciliate snapping off the scrap.
While this works okay, it’s a bit tedious and also leaves some inconsistencies that need to be sanded out. On the second ring, I realized that if I scribed the circles just a bit deeper, I coud snap the scrap out directly, leaving a much smoother and rounder edge. It also took 1/3 the time.
I also was being really ■■■■ and actually laid out the 1/6 spacing for the internal bracing. An absolutely meaningless exercise that will never, ever be seen by anyone. But it was fun.
To glue on the top piece I used some angle blocks to hold the edge in line. Liquid cement all the way.
I test fit the stack to see how it all aligned.
And then I fit the upper and lower annular rings into the drum and was rewarded with a nice rounded drum. I was almost tempted to glue it at this point, but it was very near quitting time and I didn’t want to do anything rash. I’ve said it before, “I am not patient! I am persistent!” It’s that persistence that has me doing stuff two or three times until I perfect the method, but I will screw up when I don’t allow time for glue or paint to dry.
I’ve created the development drawings of the barbette pieces. I don’t have a working CorelDraw any longer, and am not in a position at the moment to buy a piece of $400 software. I have Inkscape and MyDraw. Both are decent, but neither works for me to make full size templates on US Standard Letter Pages.
Coreldraw is simply the best vector drawing program I’ve tried. It does several things that really help. First, it enables you to move the ruler origin anywhere on the drawing page. It makes it so much easier to establish accurate guidelines when you can set zero at the edge of the object. It also enables you to tile prints that exceed the size of your printer’s page. I can’t figure how to do this in MyDraw at all, and in Inkscape you have to export pieces of the drawing as separate PDF files, which is a total pain in the butt!
I ended up printing a page scale image of the three templates with their 1:1 dimensions. Two of them are fully rectangular and will be easy to layout on the styrene. The other has a simple curve on top and bottom edges and I will work that out somehow. Corel also enables scaling very easily. I also have skill with Adobe Illustrator and found it too to be clunky and difficult to use.
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Perhaps a silly question, but have you considered using SketchUp to make these 2D drawings? I think it is possible to print to a user-defined scale (such as 1:1), though it has been years since I’ve tried it and I recall it was a bit finicky.
I have SU pro 2022 and have attempted to use Layout for this purpose, but can’t seem to get it scale properly or figure out how to do the multi-page print challenge. In other words, I’m in the same place as I am with the other vector programs. I have CorelDraw 2017 installed on a Windows partition on my MacBook Pro using VM Fusion as the Windows emulator. It worked great for four years. All of a sudden somebody did something and CD no longer boots up. It starts to boot and then abbends. I’ve contacted them and VM and neither can find out what’s going on. The new CD 2022 finally has a Mac version so I can scrap that partition nonesense. I will do some more experimentation with SU and see if I figure something out.
I bet that @DaveR (and other forum members) can help to explain and demonstrate Layout features.
I will pose that question. I really need to solve the CorelDraw problem.
In order to ensure that I can butt glue the tapered portion of the lower shell to the previously-built straight portion. I needed to have an adapter that combined the straight and angled portion which could provide more gluing surface. Enter the 3D printer. I drew a curved adapter on SketchUp matching the included angle. It printed in 1 hour and 15 minutes and was just what was needed.
I cut out the tapered portion from the newly acquired styrene sheet using the glued-on-pattern method I used before. I glued the joint plate on one side, but did not glue the cone together. I waited to do this until the cone was almost entirely attached to the straight section, thereby taking up the slack as I went along and adjusting as I went.
I used Gel CA to hold the adapters around the perimeter. The annular rings ARE NOT glued in, but later some thin CA did get down then causing a minor panic, since there’s a lot of stuff to do before I permanently glue them in. I got it loose quickly.
I could really use some longer clamps to get down the wall’s height a little better, but I made due.
Gluing started out at the back center and worked around both ways towards the joint section. I glued the piece to the adapters using thin and med CA while trying to keep the long junction as close in contact as possible. I glued that line with solvent cement. There will be filling and filing to do, but that’s to be expected with pieces of this size and nature.
As with the other pattern-taken-from-SU-Unwrp and Flatten parts that I cut, there was a length discrepency here as well. In this case the flat part was short. To close this gap I’m filling it with some thing strips to better conform to a curve that would be difficult with such a narrow single piece. I can do wonders with filler and it will be fine. Besides, this is at the back of the model and will be covered by the upper barbette shell so it will be out of sight.
Just for fun, I decided to see how the roller track fit. This was a critical test and it passed with flying colors. The 3D printed part just dropped right where it was supposed to go. Amazing! The one dimension that I haven’t tested yet will be the pan deck sitting on the roller track and how much room will be below it. In other words, will the interior stack line up as it’s supposed to. I have absolutely no idea. It fit in the drawing… Hopefully it will fit or the shell would be too tall. I can fix too tall with some surgery. Too short would be a pain the butt…
Next session I’ll do the exterior filling and sanding.
I also cut both layers of the top barbette. Again, I’m not so sure about their lengths either, but I’ll figure it out. This thick barbette armored piece with be fabricated with an outer layer, 1/8" styrene spacers and then an inner sheet which, when all glued together and finished, will look like solid 14.75" inches of solid armor in 1:1 scale.
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Only had a bit more than one hour in the shop, but made it productive. I got the upper armored barbette shell glued up. All that’s left is the slightly tapered (bottom o.d. slightly larger than top o.d.) shell and all the sheet stock parts will be constructed.
I used 1/8" square Evergreen bar stock to provide the spacers that will give the armored barbette its scale thickness. I spaced them every two inches and doubled up where the inner shell’s joint was going to fall.
I glued this to the round shape like the others with a splice plate and lots of strategic clamping. I never get it to adhere evenly across the entire face, and after some drying time, I went back and shot some thin CA into the gaps and changed the clamping scheme.
There was still some residual misalignment and gapping so I filled this with Bondic, power and hand sanded it all flush.
I then prepared the inner shell with it’s splice plate and got ready to join it to the outer shell. I was suspicious that the inner shell looked a little short so I made the splice plate a little oversized so there would be more room for the additional stock needed. It wasn’t much, less than a 1/4" Again, I started gluing the inner shell to the spacers at the point opposite to the final joint so the slack would build towards the joint.
Here is the final joint over the double spacer.
And here’s how the pan deck fits within the barbette upper drum. It fits closely like the prototype.
Tomorrow I will continue building the lower barbette skirt. The lower shell that I built yesterday joins the barbette structure at the lower edge of the lower barbette shell tieing it all together. It’s still chanllenging getting this big sheet stock stuff together, but I’m encouraged that it’s going better than expected.
Believe it or not, there was still one more part to print. This is the stationary hydraulic bumper that’s affixed to the upper tapered shell on the lower assembly and provides a positive stock so the turret could not rotate in a position to either a) run afoul of the other turret and b) aim the guns at the ship itself.
I originally was ignoring these two parts (R and L), since that part of the shell was not going to be visible to the viewer. But I awoke thinking about this this morning and decided to open the shell clamshells in two directions with only a small part permanently fixed to the back of the turret.
I will use the larger swing-away segment opening to the left that will expose the major cutaway sections, and then a smaller segment opening to expose the pinion gears and their relationship to the ring gear and roller track. I did 3D print a second hinge component and will put it to use. With that part of the shell being open, these two buffers would now be visible. Therefore, I had to print them. Took 20 minutes to draw it and 50 minutes to print them. There’s a right and left, but I only drew one hand and then mirrored the other one in the slicer itself which has this feature. As usual I print more than I need.
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Work continued today on the barbette shells. I didn’t have a full-size pattern to trace cut the lower barbette skirt, so I did by taking the measurements from the non-scale drawing I printed. As with the other flat developed surfaces, I susepected this would need some tweaking and it did. To draw the long developed curves all I had was the mid-point height. I bent a steel ruler to form the curve and traced with a pencil. I only did one quarter of the curves (top and bottom) and then used the scrap piece to trace the same curve on the top. I cut the top and then used the same piece to trace the last curve on the bottom.
The piece was almost the correct length needing a little over 1/8" trimmed off the end to fit the upper barbette’s circumference.
In order to provide some substance I inserted 1/8" square stock into the upper barbette gaps and cemented them.
Glue up of the lower skirt went off without a hitch.
I glued the lower skirt to the upper armored section. There are some gaps, but I will take care of them probably with some slivers of styrene and then filler.
As you can see here in the best cross-section drawing I’ve found, the barbette joins the lower cylindrical bulkheads just at the crease at the junction of the tapered and straight sections. I needed to make a ring to fit this space. The shells are very flexible and not absoulutely round so capturing a perfect diameter was difficult. Notice that there’s some thick stuff on the other side of the taper/straight joint very similar to pieces that I 3D printed. Seems like life imitating art here.
The o.d. of the ring is somewhat undersized and the i.d. was somewhat too narrow. I was able to remove the excess stock from the inside diameter and get it to fit. I’m going to remake this ring with the new measurements. I’m out of big stock, so I’m going to make the ring out of multiple layers in segments with the joints staggered. I have lots of smaller pieces to do this. Having this ring correctly fitted is critcal to a good job.
I tried dropping the barbette over the lower assembly and it sort of worked.
But… there’s a wrinkle. There’s always a wrinkle. The ring gear assembly has to fit within this space. It was another challenge to locate that critical part within the stack. And guess what? Those supports that I added earlier in the day were in the exact spot the ring gear is supposed to lie. I suspected adding something that thick would come back to bite me. It did.
In this picture, the ring is sitting too high.
That leaves me two choices. i can attempt to remove the supports wihout distroyings the structural integrity of the lower skirt’s joint, or I can notch the ring gear at each support and thereby get it to sit a the right height. Or maybe there’s a 3rd choice…perhaps I can split the difference. Remove some of the support and cut some shallower notches. That may work. More crafting. I will repeat myself. I suspected making these large tapered/cylindrical aspect of the build would be most ambiguous and I was correct. It will work out in the end.
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Truer words have never been spoken.
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Yup!
I started a short session by filling and sanding yesterday’s joinery. I am using some styrene strips to fill the big gaps and then use filler. Filler doesn’t like filling empty air. This will have all night to dry and I’ll trim and finish the filling tomorrow.
I also needed to get accurately cut truncate pieces. My first attempt at tracing the opening was way off becuase I was tracing the opening WITHOUT the bottom ring to stabilize the cylinder. As I pressed the cylinder down on the sheet stock to trace the opening it distorted and the cut piece didn’t fit. It re-did it, but this time with the ring installed and taped in place. I got two good tracings. I then did some final fitting and taped it in the opening to see how it worked.
I then had to figure a way to structural support this to glue it and came up with this. I was tempted to glue it, but held off because I have to be sure that I can get the annual rings into position, and these flat pieces close down the bottom opening. I’m at a point where the sequence of assembly is going to get real serious really fast. Some things better go in before some other things or it will not go togther.
I needed to adjust the size of the upper projectile flat ring since the i.d. of the space where it’s going is slightly narrower than the lower projective flats ring and it was also impacted by the those junction pieces holding on the tapered section. I needed to get an i.d. measurement of this space. I even resorted to making a measuring device that I could transfer those inner diameters to set the calipers for circle cutting. My dividers didn’t open wide enough (just a skosh over 6") necessitating the creation of a makeshift measurement transfer device… two pieces of Plastruct I-beam and an aluminum clamp. This worked, but the measurement I kept getting was the same as the ring I already had. I ended up marking the ring where the junction peices were. I notched the ring leaving the lands to actually contact the cylinders walls.
Then I tried like crazy to redo that spacing ring and still couldn’t get it the right size. Yesterday’s ring was a good 1/16" undersized. I cut a new ring, to laminate it to the existing one to give additional stiffness AND enable me to make it out of two pieces of styrene since I had no more pieces of sufficient size to cut a 6.25" circle. The pieces I cut ended up being undersized also… not as bad as the original ring, but still not right.
Then I had a flash of brilliance. The real ship uses structural steel to space and connect the barbette lower skit to the tapered inner shell. I wondered if some Evergreen I-beam would be the right size to fill this gap. I cut four pieces of the 1/4" I-beam and temporarily glued them to the perimeter at four points. And IT FIT!
At first, the fit was a little tight and distorting the inner cylinder, but then I realized that I was inserting the inner sleeve too far and getting to far into the tapered section. After carefully marking the actually overlap distance, the I-beams spacing was pretty darn good. I only need the I-beam pieces to be as long as the overlap. I went back and trimmed the ones I cut to this depth and then cut a bunch more using the Chopper with my depth stop mod. I then reglued 8 equidistant around the perimeter and tried the fit again. Here’s a vertical view of the intersection. Having the exact same sized spacers around the perimeter ensured that they are sitting in perfect concentricity.
In this view you can see which is the foreward direction. The truncated cuts aren’t symmetrical…. they taper towards the bow since the ship at #1 turret is already starting to get pointy. It’s helpful to me as well since I can easily keep track of the orientation.
In this view you can see which is the foreward direction. The truncated cuts aren’t symmetrical…. they taper towards the bow since the ship at #1 turret is already starting to get pointy. It’s helpful to me as well since I can easily keep track of the orientation.
Again, I held off gluing all this together. I need to access the lower cyliinder a lot and will install the upper barbette later on. I also happily found out that the connection pieces I added yesterday DO NOT run afoul of the ring gear. They sit well above where the ring gear goes. It sits right on top of the lower tapered bulkhead’s top edge. And that’s a happy thing.
I also will set this up with a surface gauge to ensure that the top mounting surface is parallel wit the base before I glue it for good.
When all this is glued up as a solid I have to cut it apart for the clamshells. I also decided I’m just going to make a small cutaway to display the pinion gear area and leave the other clamshell as I originally was going to do it. I have to keep in mind where the 1/8" spaces and the I-beams are since I don’t want to have to slice through any of them. That would be bad.
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I’m just about ready to prime all the outer bulkheads. After noodling it around a bit, I realized that I had to glue in the truncated faces now. There was too much fussing with it to have all the other ring decks in place. My styrene “fingers” worked pretty well, but I had to take care with the clamping. Thin styrene under action of solvent cement can decompose a bit and break rather than bend. I did break off a couple before I backed off on the clamping force.
On the front side of the joint I went around a filled it with Med. CA after pre-spraying with accelerator. My Med CA is aging a bit and needs a lot of help to get it to kick. I used my MicroMark power micro sander to knock off the high spots. I did mitigate the lumps by squeegeeing the CA with a straight razor blade before it set up.
After more sanding with various sanding sticks (wet with water), I filled it with Tamiya Filler and then sanded that when it set up
Meanwhile I was waiting for the massive filling job on the upper barbette cylinders to dry so I could get that contoured properly. Before the end of the day, all of that filler was sanded, refilled and sanded again.
All the filling is now done. I test fit the rings to make sure I could assemble them with the truncated parts now glued in. I was able to put the lower ring in by angling it, and getting in the upper two circular annular decks from the top. They all fit nicely.
This view clearly shows how I notched that upper ring. I described this in words last post, but the picture is much more descriptive.
I also used a surface gauge to trace the top edge of the lower bulkhead assembly to ensure that it was parallel to the base. It wasn’t! I set the surface gauge scribe to the lowest point, and scribed a line revealing all the high stops. I cut off the excess plastic with a diamond-coated abrasive cutoff wheel and then a sanding drum on the Dremel Flexi-Shaft. I then sanded it flat on a piece of wet-or-dry emery paper glued to my granite surface plate. It reduced the overall height by about a 1/16" but that won’t matter in the scheme of things. I re-scribed the witness line for the barbette’s lower edge since the earlier line was based on the old top edge out-of-parallel line.
Here’s the entire bulkhead stack ready for glue up.
I was going to prime everything before gluing. I’m changing that. I’m going to glue the stack, then split it. Splitting it could make a mess so I’m not worry about paint. I will prime everything then… inside and out. Furthermore; it will be easier to paint and detail the annular decks. I’m depending on all those annular rings and the doubling of the upper barbette shell to keep the cylinders from opening up. It should be okay [:S]
Here’s the stack from the outside showing all the filler necessary to make it look nice. This is the seam side and it will be facing rearward, so any imperfections (albeit minor) will not be viewable.
This is the viewing side.
As I said before, this was the most challenging and ambiguous aspect of the build for me. With it now complete and ready for final assembly, the rest of the construction should move along nicely. The change from this raw material to finish painted parts will be dramatic and I am looking forward to it.
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Rare Sunday night report…
First of all, even though we live in Louisville, KY, we spent the first 64 years of our lives living in and around Philadelphia and the Phillies are now going to the World Series.
I’ve been troubled trying to figure out the best way to add a small detail on the model—the ladder rungs attached to the central column. I was going to use wire to make these, but the question was how to install them off the model and then get the column through the holes in each deck. I could install them off the model and cut relief notches in the decks so the rungs could pass through. While this could work, it seemed a bit dubious.
This morning the thought came to me to 3D print the rungs—correctly shaped I might add—with just a small substrate underneath to a) space them properly and b) facilitate their installation.
This is what I drew:
By building in the correct curvature for the 5/8" column, and keeping reasonably thin, the substrate would practicaly be invisible. I need three sets: Powder flat to Proj. Flat 2, Proj. Flat 2 to Proj. Flat 1 and Proj Flat 1 to the Electric Deck. I made five. The rungs are very fine and will surely break some.
The print took less than hour and here’s the results.
I trimmed this one just a bit and then post-cured it to see how tough it is, and it will do just fine. I can now install the ladder rungs along with installing all the other apparatus on each deck before placing the next one of top. You can just see the slight curvature of the substrate so it will nestle into the column’s curvature.
Boy! Having that 3D printer does magical things!
Tomorrow will be a full work session. Hopefully I’ll do some more outdoors painting since the weather will be perfect.
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The ladder rung sets are cleaned up. I used a different end nipper with very sharp edges to carefully remove the supports attached to the rungs themselves and was rewarded with very little breakage. I got three perfect pieces out of the five. I used the Dremel with Flexi-shaft with a spherical diamond burr to clean off the majority of the support nubs on the back. I then attached a piece of self-adhesive fine grit sandpaper to the same piece of tubing that’s going to be the central column and finished sanded the back.
With the back contoured correctly, the fit is really good. I won’t be installing these until the decks are in place. I will install them before the deck above gets put in place giving me good accees to the column. The Xacto knife gives a good indication of scale.
I put these away in a plastic cup with a lid so nothing will happen to them until I’m ready.
I had sort of a milestone day. The three ring decks are now glued in place. I also used epoxy putty to fill any remaining gaps to the shell walls and waiting for that to cure.
Before installing the number 2 ring, I needed to do a slight modification to the ring. The powder flat walls, being 3D printed, were not perfectly circular and the projectile flat didn’t sit nicely on it. It would rest on one side, but fall in on the other. I made a single-layer, slightly smalled i.d. ring, and glued this to the projectile flat one’s ring bottom, thereby making a nice seat for the proj flat to rest on.
There were some gaps in the ring’s fit due to some slight out-of-roundness of the shell. I made some 0.040" shims that I glued to the ring before installing. I tapered the ends of the shim so it would transition smoothly to the areas that fit tightly.
With that change, I was able to assemble, not glue, the #1 projectile flat ring which now rested squarey on the powder flat, and tested this by dropping the projectile flat onto this. When it was aligned nicely, I first used solvent cement, and then filled bigger gaps using Testor’s tube cement. I let this cure a bit and then got ready to do proj. flat’s #2 ring.
My concept of notching the ring to fit into the spaces between the 3D printed transition pieces didn’t work. Reason? When the lower ring was actually glued in and tight, the cylinder no longer flexed enough to get this ring in with those nubs sticking out. They had to go. No loss… I also shaved some stock off the lower ring in the assembly so it would slip over that sharp edge of the 3D printed transition pieces. With that change the ring got into position. I double checked by height marks on the cylinder’s i.d. since the stack was now 0.040" higher due to that extra spacer ring I added to proj ring #1. I then set a small combination square to that depth. I started gluing at one quadrant with the ring pressed up against the square, then went across the diameter, and again pressed it against the square and glued it. I finished up with the other two quadrants using the square.
This ring needed to be glued in with CA since the UV resin is unaffected by solvent cement. I used only med. CA. I went around once, added more accelerator, and then filled more gaps. There were still more gaps. In this case I used Milliput epoxy putty. The material was still not fully cured at the end of the session. I will do some final finishing on this tomorrow.
I could now go back and remove the powder flat and finally glue the bottom ring into place. Again, I used a combination of solvent cement, tube cement and med CA. With the lower edges of the truncated flat finally glued to the bottom. I went around and did final sanding and filling of the lower cylindrical structure.
I measured the spacing for parallelism between proj deck 1 and 2 and was rewarded by the tolerance of a max of .004" around the circumference. This accuacy will be appreciated when installing the deckf supports.
Everthing will be cured tomorrow and I will do any final finishing. I will then glue the barbette portion in place. When that’s dry, the GREAT SPLITTING will take place and we’ll see how it all hangs togther. After splitting I’ll install any angle supports and deck girders (already printed) and then do the priming and painting of this major structure.
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Short workday… PT, but did some good stuff. I added some more spacers around the perimeter of the Barbette/Lower Bulkhead junction. The interface between the two is just a bit over a 1/4" long and it’s critical. I didn’t have any more of the 1/4" I-beam so I substituted some 1/4" square stock. It’s not visible, so it doesn’t matter. It’s not very secure. The only place I didn’t insert it was at the splice plate where the gap was significantly narrower. The picture is looking bottom up which is why they’re out of sight.
While this was setting I actually started some finish painting, putting on a coat of Tamiya Flat White with the airbrush on everything that was going to be white. I did NOT do this on the insides of the rear gun compartments or the back bulkhead. The Tamiya Flat White Primer is pretty white and I wanted this coat to no be dissolvable by Tamiya alcohol based paints. If I overpainted them with the flat white, I would need to seal the surface with Dullcoat so the colors wouldn’t bleed.
I didn’t take any pictures of this painting since you can’t really see any difference with the primer coat.
I needed to have a secure way to tie all this flimsy styrene sheet stock to the wooden display base so I drew something that would do the trick. Two of these brackets will tie the shells to the base. They’ll be in back and not easily seen. The center pieces will be held by the center column. I have a nice supply of M4 button head screws that will be held with nuts on the inside (or outside… whichever works best).
They just finished printing. I will be splitting the shells tomorrow and will be adding these brackets before painting.
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