A journal following the history, design, construction and operation of Bernard Kempinski's O Scale model railroad depicting the U. S. Military Railroad (USMRR) Aquia-Falmouth line in 1863, and other model railroad projects.
©Bernard Kempinski All text and images, except as noted, on this blog are copyrighted by the author and may not be used without permission.

December 30, 2012

B&O Ironclad Car Finished

I finished the B&O ironclad car except for the gun port, some minor clean-up and touch up. I had trouble finding a good way to simulate the iron rail armor. It sounds simple, but getting the code 55 iron rail to create a realistic appearing armor in 1/48 scale was not easy. I tried four different techniques but ended up using a laser cut taskboard layer for the armor with separately applied bolts and washers that I laser cut. I did not use the first model I made shown in the previous post.

I added some barrels and boxes inside the car. There is also a field gun inside.
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Next is the B&O box car with the infantry firing ports.

December 25, 2012

B&O Ironclad Cars

I started building 1/48th scale models of the B&O Ironclad and Rifle cars.  These models are destined for the B&O Museum collection.  I am working with Dan Toomey of the B&O Museum to try to make these models as accurate as possible, but given the limited and conflicting information we have about the cars, much is educated guess work.  For example, there are several descriptions of an engagement where one of these cars was destroyed. Each account has different descriptions of the car and its construction. Most of them are summarized at this web site . It's is hard to know which one is right.

The cars are described in Alan Koenig's dissertation, "Ironclads on Rails: Armor Returns to the Battlefield, 1861-65. This was our main source as it cites several statements from the builders, as well as  observers that saw the car in service or after it was destroyed.

The ironclads are also mentioned in Robert Hodges, Jr.'s book, "American Civil War Railroad Tactics." The latter includes an artist's concept painting of what the cars may have looked like as no known images of the cars have survived.  While we agree with the overall look of the cars in the painting, there are certain details we will change.

The drawing shows our interpretation of the cars. The approach we used is to assume they started with standard boxcars and added the armor as an applique. These cars were built quickly, so it seems likely they started with existing parts if not whole cars.

According to Koenig, one source says the armor was mounted on a 45 degree angle. That is possible on the front of the car, but not possible on the sides as it would make the car too wide. So we made the side taper more vertical.

Koenig lists one source that states the rail was "T" iron, while another just says "railroad iron." We elected to go with "T" iron, in the form of code 55 rail, which works out to 2.6 inches in full scale. At this point most major railroads were installing 60 to 70 pound per yard rail on their mainlines, which scales down to about code 90 (0.093 inches inches tall). So the rail on this car represents lighter rail that was either destined for yard use or was retired. I had a bunch of code 55 on hand, so I used it.

Is code 55 reasonable? Yes, because heavier weight rail would have overloaded the 10 ton capacity of the car,  which was typical of a box car of the civil war era on two trucks.  The table illustrates that at 30 pounds per yard of rail the car would weigh about 10.2 tons loaded with crew, gun and ammunition. Even rail at 40 pounds per yard would have overloaded the car by 30 percent.
Heavier 60 or 70 code rail would have seriously overloaded the car. (Note that the number of rails per side for larger weight rail would be less than shown here as the the heavier rail is also wider. But the weight increases with the cube of the size, so the weight gain will out-pace the width related savings.)
"T" Rail added by the crew to protect the casement corner on USS Cairo

Some sources say the rail was spiked on, but Dan believes that it was bolted. I used the railroad T armor on the restored USS Cairo as a guide for how such rail would have been bolted on. In the case of the USS Cairo, the rail was bolted with the flat side facing out. I reversed it on the car as it was too hard for me to get the code 55 rail to look correct in that configuration. It would not lie flat as I assembled it.

Most sources state that the cars were equipped with one gun each, mostly small mountain howitzers, but one had a 6 pound brass smoothbore.  The first versions of these cars had cannon mounted in the vehicle suspended from the roof with a series of ropes. But later versions used standard field carriages as we show here.

There is a gun port on the front of the car. The artist concept in Hodge's book shows gun ports and cannon pointing out the side, but the car is too narrow for the standard field cannon to fire to the side. So there is no point to have gun ports on the sides, though there may have been observation ports. We elected to include 3 loop holes on each side instead of additional gun ports.

These cars were operated in sets. An armored train would have ironclads on front and back, with rifle cars between the ironclad and the locomotive. So a gun pointing out from each end of the train might be effective in covering the area around the train, especially if the gun could cover a 60 degree arc from its embrasure.

The gun port was reported to be 6 inches square, but again that is unlikely as such a small size would not allow the gun to defect or elevate very much. The gun port must be a bit bigger. One source, Deffinbaugh, claims he found the gunport of the destroyed car and that it was a solid piece of iron.

The last puzzle was the rear of the car. Again according to Koenig, one source says the rear was also sloped with an embrasure for a gun. But most other sources say that only one gun was mounted in each car. If you put a 6 pounder smooth bore on a standard field carriage on a rail car that can travel along standard gauge tracks, there is no way the car can be wide enough to turn the gun around inside the car.  So one gun cannot serve both gun ports.  It seemed impractical to me for the car not to have a decent size access door, so I added one to the rear.

One of the problems I have noted with some artists' concepts and drawings of artillery mounted on flat cars is that they make the gun carriage too small in relation to the car. The drawing above shows both the gun and car in the same scale.  As you can see, a 6 pounder on a standard field carriage just barely fits in the car. There is some room to deflect the cannon right or left to aim, but firing off the side is not possible.

We welcome your comments or ideas. The famous ship historian and modeler Howard Chapelle once said words to the effect that you should never build a model until you have all the information you need, as others that view the model will not know where you guessed. (for more of Howard's argument see this link.)In this case, we recognize that the information is sketchy about these cars and do not claim that this is a 100 percent accurate representation of the car, but the best we can make.  We hope you enjoy it.

December 20, 2012

Rail Gun Encased

The Land Merrimack posed on my O Scale layout.
I added a diorama pedestal base and acrylic dust cover to the rail gun model. The base is a solid plank of cherry that I cut and routed into a base. It matches the base for the Dictator diorama. I still haven't perfected the acrylic case technique yet, as I got a glue stain on the top surface. But it will serve the purpose of protecting the model from dust and fingers.

The section of track is code 100 rail on hand carved poplar and basswood ties. I added some grass tufts and various leaf and pebble texture to the soil. All it needs is a laser cut name plate and it is ready to display. I haven't decided if I should add a figure to the diorama. It might help provide a sense of size and scale. The model is built to 1:32nd scale.

December 13, 2012

Rail Gun - Finished

I finished up the remaining details on the rail gun. I replaced the coupler on the rear. The first one was too big.  Since I laser cut the parts from 1/16th inch acrylic, it was a simple matter to reduce the height of the center part and and reinstall it. The nut detail is actually engraved. The coupler simply is glued to the wood frame.

The brake wheel hangers were the next challenge. I made the parts from 0.020 inch strip brass, a .042 inch brass rod and an etched brass wheel from my spares box. To fashion the parts I used my drill press with an x-y table to drill holes in a straight line. Then I used a new sharp  file to shape the parts. I secured the parts to the model and then added NBW details with CAA. I added a cast white metal gear to the shaft to represent the locking pinion.  To simulate the pawl, I added a small silver of wood.

I had to use brass for the parts  because the next step involved soldering the brake chain to the wheel shaft and the brake linkage on the truck. With everything soldered up, I tested the brake mechanism. It does work, though it would need some adjustments if this were to be an operating model.

Next I added an elevation wheel to the gun (not visible in these photos). I also mounted a small rod on the bottom   front of the gun carriage and added a wood strip with an iron strap on the rear. This allows the gun to deflect a limited amount in the casement while also tilting the gun forward. The tilt allows the gunners to run the gun out for firing, while the up slope helps absorb some of the recoil.

Next I must build the base to display the gun, and an acrylic case to protect it.

Having studied this gun, I am convinced that it was built solely as a weapon to counter other rail mounted iron clad guns. The heavy 32 pound cannon is impractical as a field weapon against mobile infantry and artillery targets. The limited traverse also hinders its use as a general field piece. The heavy armor only on the front meant that they did not expect it to be engaged from the sides.

To my mind the design of this gun supports Dr. Schneider's thesis that this was the "Dry Land Merrimack" that Lee had Brooke build for the Peninsula Campaign in 1862. They built the gun as a response to reports that the Union were also developing an ironclad  railroad gun. The Lee-Brooke gun was used once, probably found impractical as the Union did not have a matching railroad ironclad, and then retired to a siding, where it was discovered a few years later by Union soldiers.

December 12, 2012

Rail Gun Update

I am almost finished with the Lee-Brooke Rail Gun. Here are some shots showing the model. I attempted to add any detail visible in the two existing photos. Everything on the model except the wheels has been built from scratch.

The iron armor is laser cut and engraved acrylic.
I still need to add the brake wheel and the cannon elevation wheel.  With the brake wheel installed, the brakes will work.

I plan to make a solid cherry pedestal and acrylic case for it to match the existing Dictator mortar model. These will be on display at the B&O Museum next year starting in January.

December 10, 2012

Baltimore Harbor layout

Holiday parties create a nice break from layout work. Making strawberry Santas and cupcakes is
much like making scenery, just more tasty.
On Saturday I assisted Paul Dolkos in hosting an open house for the NMRA. Paul is building a new layout with a Baltimore industrial harbor theme. The layout is about 40 percent complete, though most of the track is installed and operational. My job, along with Bob Warren, was to keep trains running while Paul entertained guests.

Here is a shot showing me switching the Western Maryland car float at Wagner's Point on Paul's layout.  (Photo by Gerry Fitzgerald).

After Paul's open house, Gerry Fitzgerald and Gabriella Petrick visited the Aquia Line. It had been about three years since Gabriella had last visited so there was lots of new stuff to see. It was a fun visit, enhanced with some homemade raspberry vodka provided by a colleague from work.

December 9, 2012

Civil War Ships Models at the Navy Yard Museum

 The US Navy Museum at the Navy Yard in Washington, DC is one of the least known, but best museums in the area. Here are photos of some of the ACW era ship models there.
CSS Virginia in drydock

USS Miami, a double ended gunboat

Mighty Mo!
Probably the most impressive models in the museum are the 1/48th scale aircraft carriers and battleships built by the ship contractors. These are huge and highly detailed.

December 1, 2012

A cupcake too far

Gerry Fitzgerald and Joel Salmons stopped by for today's cupcake, I mean work,  session. Brian and Michele also stopped by after the Scottish Christmas Walk to have a cupcake and check the  progress. Last, but not least,  Doug Gurin, the now famous Model Railway Show podcast personality, stopped by for a status check, plus a cupcake and slice of Gerry's infamous chocolate cake from Charlottesville (too bad most of us are on diets).

Gerry and Joel score and snap the pink foam
Everyone was satisfied with the LED lighting, drapes and bunting. So we moved on to installing the pink foam layer. But first we had to make a trip to Home Depot to get supplies to finish the walls for the staging yard. Little did we know that we also needed fresh tubes of adhesive for the foam. Because when we got back, we discovered that the tubes of adhesive I had on hand were old and seemingly partially set. But, we were able to get enough adhesive to stick the pink foam panels to the benchwork.

With the panels glue setting, we did some mockups with laser cut track templates and a bridge mock-up.

Pink foam installed on the first two sections

Mocking up turnout locations using the mini-mock up as a guide

Weighing down the foam while the glue sets

A laser cut cardboard mock-up of the bridge.