1:72 Complete Iowa Battleship 16"-50 cal Turret with interior down to the magazine

Looks great so far!

Your wait is over. Here's the next posting. I too am very anxious to see it come together. I'm still waiting to start doing the detail painting.

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.

My goodness me, that sure looks solid. Nicely done.

Wonderful work!

Good work so far!

Not as solid as it looks, but it will work.

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.

Lovely work so far!

Wonderful work!

Thanks for the encouragement, guys!

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.



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.

Where there's a will there's a way and I applaud you for the way you approach all these little (referring to the scale) problems.

Necessity is a mother… or so they say. You have to trust the force.

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.

Great work so far!

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.

Good thinking outside the box and what delicate little ladders they are.

I just agree with you 'bout the printer......most of the time magical, sometimes really a Hell

Oh yeah! It can be frustrating, but like childbirth, good stuff sometimes hurts. Without 3D printing this massive project would not have even been contemplated. I know there are scratch-builders out there who could have fabricated some of this old school, but I can't (or won't). Gibbs and Cox made fabulous 1/4" scale models of US Navy ships and they didn't have CNC, laster cutters or 3D printing.

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.