Turret Revised

I revised the turret based on the most recent information I had. Relying on Alvah Hunter's description, combined with studying the three engineering drawings, plus two artist sketches of the turret interior of Passaic and Montauk, plus some educated guess I arrived at the following turret roof configuration. All the parts were laser cut. None of the references were entirely consistent, so I had to make some decisions. The turret frames are 1/8th inch plywood. The simulated iron rails and the wood grating are laser cut 1/32nd inch plywood. The perforated iron plate is laser cut resin impregnated backer board.

512 Rivets, each made from a sewing pin, individually trimmed to size and inserted in a drilled hole. Whew! And there are more to go!

The turret on its base with the pilot house added. Still lots of detail work to go. The circular hole is for the smoke box vent.

The photo below demonstrates how the turret will be removable to allow one to view the guns and other to be added details. I haven't decided if I want to make the pilot house removable, as it is needed to support the to be built awning. The two holes are for the bottom axles of the armored port hole stoppers. One will be inside the smoke box and not very visible.

The turret will be removable to allow viewing of the guns and interior.

I have consolidated several drawings of the turret interior that I found on the web below for  ease of comparison. I annotated some to note discrepancies or other items of interest.

This drawing shows the best view of the smoke box. Note the quilting on the walls and the perforated iron on the roof. There is no visible ladder to the pilot house in any of these drawings but text descriptions describe a hatch. The ladder was probably removable. Note how the XV inch gun is on different sides of the turret in the various drawings.

This view shows gratings leading to the turret chamber below the turret. Note the thin ladder in the background, compared to the stairs in the Montauk drawing. Hunter describes a removable iron ladder. There is no smoke box on this drawing.  Both drawings show a bolted ring under  the pilot house.

A good engineering drawing showing the port hole stoppers (that are different sizes) and the smoke box.

No smoke box in this drawing. Did the Passaic have one or was that a latter addition? Hunter describes how the smoke box was not particularly effective and was damaged by the blast from firing the gun.

Here are some questions people have asked about the turret and my answers based on my research.

-The engineering drawings show the stack and the vent hole from the stack, but as the turret traverses, it would seem that the stack would be venting into the turret unless the alignment is perfect. How's that work?

The pilot house was fixed to the hull. The rest of the turret rotated as a single unit. It was actually hydraulically lifted a couple inches to rotate. The turret was supposed to be sealed at the turret-hull base, but the seal leaked, so they caulked the turret when they went to sea. The rails and perforated plate were held in place only by gravity. Hunter describes an accident where the plates were knocked loose by an explosion. The iron ladder that was stored on the turret top was blown over board and not recovered in the incident.


The turret had wrought iron plates covering the rivets, an early form of spall liner that is currently used on armored vehicles. These prevented incoming shot from sending  sheared-off rivets flying around the interior of the turret. However, a pilot was killed in the battle for Charleston when a shell sent a rivet flying in the pilot house, which apparently was not so equipped.

-How'd they ventilate the turret when firing the guns? [And can you imagine the noise in that small, all-metal space? --WOW!]

There were two blowers in the hull under the turret, in a space they called the turret chamber. These blowers drew air through the ship and out the turret. The hull was water tight during sea movement. They actually sealed the hatches and caulked them as the installed rubber gaskets were ineffective. Later they added hatch and ventilator combings that allowed better air flow through the ship.  


The XV inch gun actually fired with the muzzle in the turret. It had to be LOUD!

-How'd they get into the turret from the deck?  And for that matter, how'd they load food, powder, shot and so on?

There were removable ladders from the turret chamber into the turret and from the turret to the turret roof. There was a ladder on the external side the turret. When underway or in battle to exit the ship you had to go from the hull to the turret chamber, up a ladder into the turret, up another ladder to the roof and then down the external ladder. They used the turret roof as a quarter deck when underway, as the deck was awash.


There were other hatches on the hull deck for loading supplies and ammunition. The ship had a steam condenser to make fresh water.

Learning to count

Something didn't look right with the turret armor. Sure enough, I had miscounted the number of armor panels. I had 14 but there were supposed to be 16.  So I ripped off the armor wrapper and made a new one.

I also decided to redo the turret roof using the same basic design as used on the USS Monitor. The Monitor had railroad rails under perforated plate. This photo shows the Monitor turret under conservation at the Mariner's Museum in Newport News, VA.

So while I was at it,  I ripped off the roof and made a new one. Since I didn't have any the images of the Passaic turret roof, I am going with this. I think it looks more interesting too. The Passaic was essentially an improved Monitor, so this may even be right.

Alvah Hunter describes the railroad rails and perforated iron plate construction in his book, "A Year on a Monitor and the Destruction of Fort Sumter." He also describes wooden gratings over the perforated plate on top of the turret. He mentions removable ladders used to get to the top of the turret, but did not describe how to get into the pilot house. He mentions only one hatch, so I may need to revise my turret roof again.

The revised floor has a perforated deck. I may leave the hatches open so that the guns and interior would be
partially visible through them.

With the correct number of armor panels all the rivet and panels line up correctly.

Upside down view showing the simulated rails and beams.

The photo aboves shows the  gun port inserts that fit in overly large gun port holes in the turret walls. These inserts are laser cut to the same shape as the gunport in the armor. The inserts made lining up the gun port armor and walls much easier as now I do not have to drill the gunport holes through the walls. A little bit of sanding and they where done. Once I add a turret liner, it will hide the wood layers and the gun port inserts.

The US Monitors had wrought iron plates covering the rivets in the turret. This design prevented rivet heads from becoming flying missiles if struck and broken off in battle. It was essentially an early form of spall liner a design used on modern armored vehicles. These ironclads were amazing advanced designs.

If anyone knows how the crew accessed the pilot house, please let me know. I can see no ladder or access door in any of the photos or drawings.

Armor on the Turret

I started adding the armor to the turret. I did not have detail plans for the top deck, but I did find a drawing on the web that showed an assumed arrangement. Using that plus some period drawings of the interior of the ship, I added hatches and gratings to the turret roof. This is mostly an educated guess. If anyone has a better reference, now is the time to make corrections, so please let me know.

Anyone know how the pilot and crew got into the pilot house? There doesn't appear to be a ladder inside.





The armor plating is a layer of 0.015 inch resin impregnated backer board with laser cut holes for the rivets. The rivets are fine dress maker pins that have heads that scale to 2.5 inches, the scale size. Once the armor plating was glued to the turret, I drilled out each hole with a 0.030 inch drill. Then I have to trim a pin and insert in every hole. That should take another fun few hours.




I decided to cover the gun ports opening I made in the wood turret wall with the armor plating as they did not line up with the gun ports that I cut in the armor. I'll drill out and file the wood for the gun ports once all the rivets are installed. The pilot house is a cap from a can of Testors Dullcote. It is almost the right size. I'll make the final one using the same technique I used for the main turret.

The awning supports for the top of the turret are davits from Bluejacket. They are almost a perfect match. The turret walls lift off the base, so if I decide to detail the interior it is possible, but without better information, it would be difficult.

A Turret and Some Scenery

The portholes are glazed,
 but still need detailing.

Work continues on the USS Passaic.  The task board surface on the hull texture was not as good as I hoped after I painted it, so I laser cut a fresh layer of hull plating using resin impregnated paper. It has a smoother texture that is closer to scale.

I started building the turret using a series of laser cut rings and discs. Next I will add the armor plating and rivets. The turret armor plating will be also made with resin impregnated paper. I will use sewing pins for the rivets as I found some that were the correct size and shape. I do not plan to add extensive detailing on the turret interior as I don't have great references. So the interior will be pretty basic.

While the laser was cutting turret parts I added a base coat of scenery to the Stoneman's Station area all the way to Potomac Creek. I now have at least base scenery from Potomac Creek all the way to the end of the line at Falmouth.

It is curious but with just the base scenery, the layout looks smaller. I need to add some view blocking features to break up the line of sight and add some visual complexity.

Base scenery at Stoneman's Station. The tents are just placed for planning purposes.
They are not in their final position. There will be an extensive supply depot here.

Looking from Potomac Creek to Stoneman's Station. 

It's not an Ironclad Guarantee

What is that object hiding under the Model Railroader back issues? Why it is the beginning of the hull form for the USN Passaic. I had mentioned that this ironclad was in the upper Potomac in the winter 1862. It was towed to Washington, DC Navy Yard for repairs. Presumably it sailed back south under its own power. Did it stop at Aquia for a brief visit? Unlikely, but possible.

After much prodding from Gerry and Rob, I decided to at least try the USN Passiac at the wharf scene.  I mocked it up with a piece of cardboard painted dark brown. It looked tight, but it could work. Brian K. suggested making it sub-scale, but with it being in the foreground, I decided against that.

This first attempt got
thrown away.

I started building the model using a standard ship modeling technique of plank on bulkhead following plans I found on line.  I used a straight pine 1x2 as the center keel for stiffness. I was laser cutting the bulkhead parts. Thus I had to make the longitudinal bulkheads in three lengths as my laser bed is 18 inches long, but the ship is 50 inches long. As I built the frame I realized that it was riding too high. I was building the armored hull to scale height (see plans). But when I re-examined the plans I noticed that the freeboard (the part sticking out of the water) was only about 12 inches, or a quarter inch in scale.  There wasn't any practical way to cut down the bulkhead frame. A much simpler approach for the hull would suffice.

Note how little of the hull is exposed above the waterline

So I trashed the bulkhead frame and used the laser cut a layer cake style model using 4 layers of 1/16th inch thick task board. The top layer was engraved with the armor plate and rivet detail and had the appropriate holes cut for portholes, turret, stacks, etc. I glued the layers together and by the next morning, I had the makings of an iron clad. I attempted to depict the hull camber using spacers under the top layer of task board. I probably should have put the spacers under the bottom layer to get the profile more accurate. There is also some sheer to the hull. Most photos show the ship riding lower at the stern than at the bow. I am thinking about how to show this, even though the effect is subtle.

I had earlier done a test of the task board to see how it would appear when painted to resemble iron armor. I was very pleased with the texture. As an alternate, I may try cutting some sheets of resin impregnated back board as the armor surface.

I may do a new version using a single piece of 1/4 inch plywood as the base and then add small pieces of laser cut profile boards to simulate the camber. It depends on how the task board hull holds up to detailing and painting. I am a little concerned that it might warp. One solution would be to secure it to the table surface with screws to hold it steady and prevent warping. I prefer not to glue it in place in case I need to move it if I change my mind.
The photo below shows a mock up of a possible configuration of the scene with the USN Passaic. By angling the wharf  on the peninsula and moving the paddlewheel steamer into the resulting wider section of  water closer to shore, I have ample room for both big ships. Smaller ships can fill in the other odd water areas. I want to leave space at the end of the wharf for the car floats.  I think the scene looks better on an angle too. This is looking good, but is not a sure thing.

It is amazing how close the roll of duct tape is to the size of the 1/48th scale Passaic turret.