USS Cape (MSI-2) by Dr PR - 1:48 - Inshore Minesweeper

[Dr PR]

Eberhard,

 

Thanks! But with your watchmaker's tools I think you could have done a much neater job.

[wefalck]

Before I had a lathe, I turned parts exactly the same way …

[Canute]

I salute your machining and soldering skills. Well done.

[Dr PR]

Next up is vertical ladders. I need four for this model.

 

One of the assembled ladders is shown here. It will go on the aft end of the main deckhouse, on the starboard side, from the main deck to the O1 level. Below it are the pieces of a "kit" for a longer ladder that will go on the port side of the O1 level deckhouse from the O1 level to the O2 level on top of the pilot house.

 

The ladder parts were cut from some 0.030 x 0.015 inch (0.76 x 0.38 mm) brass strip made by Special Shapes Company. They made many different small brass shapes, including "U", "H", "L", solid rectangular and round rods. Unfortunately they are no longer in business and I know of no other company that makes these parts.

 

I bought out the stock years ago from a local hardware store that was run out of business by big box hardware stores. I guess there isn't enough profit for the big store paper shufflers to bother stocking these things.

 

The actual cross section dimensions of the side pieces and rungs of vertical ladders in the US Navy were 1 3/4 x 3/4 inch (44 x 19 mm). That would be 0.036 x 0.016 inches (0.9 x 0.4 mm) at 1:48 scale, so the brass strip is just slightly undersize. All of the ladders on the MSIs had rungs spaced 12 inches (305 mm) vertically.  This was pretty common in the Navy. However, not all vertical ladders (ladder rungs, steps, etc.) were the spaced the same. When I made the CAD model of CLG-5 the blueprints often showed the spacing of the top rung below the upper deck, and the bottom rung above the lower deck. Then the blueprints said to space N number of rungs equally between the top and bottom rungs. This produced spacings from 11 to 15 inches (279 to 381 mm), although about 13 inches (330 mm) was the most common. The rungs were all 12 inches long (305 mm), although the blueprints show ladders were also built with 18 and 24 inch (457 and 610 mm) widths.

 

I made this jig from scrap wood for assembling the vertical ladders. The 0.094 x 0.030 inch (2.4 x 0.76 mm) side basswood strips are spaced precisely at the outer dimension of the ladder sides 0.28 inches (0.25 + 0.015 + 0.015) or 7.1 mm. At the center are two wooden pieces spaced just over 0.015 inch apart, the narrow width of the ladder rungs. As you can see, the ladder rung is placed in this slot. Holes were cut through the base and wooden side strips to allow a soldering iron tip to contact the brass parts.

 

More basswood pieces were glued to the base spaced exactly 0.25 inch (6.35 mm) from the right hand center piece. Really only three of these spacer pieces are needed to assemble a ladder - the center one and one to either side. But the additional pieces serve to hold the assembly in place and show any spacing errors that might creep in. The gap between these spacer pieces and the outer side pieces is the narrow dimension thickness of the brass strips, 0.015 inch. The brass parts fit tightly between the wooden jig parts.

 

Each ladder rung was soldered on both ends to the side pieces. I placed a small drop of liquid flux in each joint and then touched the tinned tip to the joints briefly. I used a metal tool to hold the rung down until the solder hardened - otherwise it would try to lift out as the soldering iron tip was raised.

 

 

The photo on the left above shows the correct way to assemble the ladders. First an end rung was soldered between the sides at the proper end position (this varies with each ladder). Then the assembly was lifted and moved so the rung was positioned one step to the right, tightly against the spacer strip. Then the second rung was soldered in place. The assembly was lifted again and moved one place to the right. Another rung was added and so on.

 

It is very important that this sequence is followed to ensure that the spacing of all rungs is equal. Starting at the middle (as shown in the right photo above) or trying to install the end rungs first and fill in the rest later will likely result in uneven spacing.

 

After the ladders were assembled they were cleaned up with files, brushes and sandpaper to remove excess  solder. Then the ladder supports were soldered on. These were made from 0.005 inch (0.13 mm) brass strips cut from a large sheet to a scale 3 inch (0.0625 inch or 1.59 mm) width. The faces of the ladders were spaced 6 inches (152 mm) from the bulkhead surfaces. That is 0.125 inch (3.175 mm) at 1:48 scale. The long legs of the supports are 0.125 inch, and the mounting "feet" were 0.0625 inch.

 

Soldering the tiny pieces in place was a test of my patience. A drop of solder was placed on the mounting surface of the supports. I used a resistance soldering "tweezer" tool to pinch the support to the ladder side and then applied a brief current to melt the solder. This worked most of the time but a few of the pieces moved before the solder hardened and I had to remove them and start over.  But I finally got them all done.

 

 

The parts were washed with acetone to remove the solder flux and then painted with acrylic paint. After they are mounted to the deckhouses they will be painted again to touch up thin spots.

 

Before making the two ladders for the ship's mast I will need to replace the two wooden pieces at the center of the jig where the soldering is done. They became charred after repeated soldering. However, most of the black stuff you see in this area is solder flux residue. I had to clean the residue out a few times to be sure the new rung piece fit properly.

Edited Tuesday at 03:25 PM by Dr PR

[Jim Lad]

Very nice looking ladders, phil.

 

John

[Dr PR]

John,

 

Thanks.

 

Here are a few more details.

 

This is my "jig" for making fire hoses, made from a piece of scrap wood.

 

The brass tube is the same diameter as the hose support in the hose racks.

 

The hoses are strips of cardboard about 0.065 inches  (1.7 mm) wide. The strips were mostly about 7 inches (178 mm) long, although there were a couple of 11 inch (279 mm) pieces. These represented 25 foot (7.6 m) and 50 foot (15.2 m) hoses.

 

The strips were wound back and forth around the tube. Then they were soaked in white school glue on the top part, leaving the lower "coils" free to hang loose. The glue eventually dried colorless.

 

 

 

 

I experimented with several types and thicknesses of cardboard.  The larger hoses here are made of 0.024 inch (0.6 mm) thick card. The others were 0.012 inch ((0.3 mm) card.

 

The thicker material is actually closer to the color of the fire hose (as I recall), but it is a bit too thick. The hoses are too large for the hose racks. The more reddish brown 0.012 inch thick card made better size hoses.

 

The white card made nice assemblies, but even new hoses aren't quite that bright!

 

 

 

 

 

Here are two hose racks on the aft end of the main deckhouse.  Two hoses were stacked on each hose rack. The hoses on the left are 50 foot 1 1/2 inch (38 mm) hoses, and the larger bundles on the right are 25 foot 2 1/2 inch (64 mm) hoses.

 

The hoses should have brass fittings on the ends but I don't know how I would open up the flattened paper strip to represent the round hose at the fitting. For now I am not going to worry about it.

 

The black dot at upper right is where the fire main comes through the bulkhead for one of the hydrant/strainer assemblies. I had to get the hoses installed before I could add other details to the aft end of the deckhouse.

 

 

This is another detail for the aft end of the main deckhouse. It is the brow (gangway), and it was attached vertically to the bulkhead on the starboard side, inboard of the vertical ladder shown in an earlier post.

 

The brow was 6 feet (1.8 m) long and 2 feet (0.6 m) wide. When used for access to the ship it had four 3 foot (0.9 m) long stanchions with chains stretched between them on the sides of the brow.

 

The thing below the ruler is a holder for the stanchions. It will mount on the bulkhead beside the brow.

Edited yesterday at 04:29 AM by Dr PR

[Jim Lad]

How did those hoses handle in practice, Phil. Ours were always on reels contained in a box - one hose per box - and were very fast and easy to deploy.

 

John

[Dr PR]

John,

 

It was easy to get the hoses off and on the racks. Because the hose isn't looped around the rack, but is just draped over it, all you needed to do was pull on the hose and it slipped right off the rack without getting tangled. Putting it back on the rack took a bit longer.

 

The "U" shaped bracket that holds the hose below the rack was actually a three piece thing with a hinged bar over the hose and a locking pin on one end. Just pull the pin, swing the bar back out of the way and pull on the hose. The 1:48 scale model bar is 0.030 inch (0/8 mm), but the blueprints call for 0.021 inch (0.05 mm or 1" at 1:1 scale). I wasn't about to try making the hinges and locking pin at that scale.

 

I should say it was usually easy to get the hoses ready for action. But in one firefighting school I had the folks running the class had prepared a damage control locker with a collection of parts where no two pieces would fit together! We had all had other fire fighting schools so on our first drill we went at it with confidence until we couldn't get anything to work. Then frustration turned to laughter when we realized this was a lesson telling us that we needed to be sure all our gear was ready to be used before we really needed it!