The Ship Model Forum

Tom,

You pick some interesting ships to model! I am looking forward to seeing how much stuff you cram onto this one!

Howard Chapelle (naval historian) once wrote a paper about which ships should and should not be modeled. Basically he said we don't need yet another Victory or Bismark and there were a lot of other interesting ships to model (this raised a lot of hackles with some ship modelers). I'm sure he would approve of your choices!

Phil

PS: This has me thinking - I have always wanted to make a model of my first ship, the inshore minesweeper USS Cape MSI-2, the smallest "ship" in the Navy. It would be 25.5 inches long at 1:48 scale, or just 12.75" at 1:96. I have the full blueprint set so maybe I'll 3D print it! It was one of the most insignificant ships ever launched so I'm sure Chapelle would approve!

_________________
A collision at sea will ruin your entire day. Aristotle

Phil:

As you know the mine sweepers had a lot of interesting gear. If one looks at any of the excellent shipyard photos of WWII Destroyers every square meter has something plastered to it. The old Four Pipers were pretty small ships and really got loaded up with their conversions, especially to the DMS. I'm not seeing a lot of standardization in these. Friedman chats a little about this in his book "Destroyers". Boggs, for which I have drawings has the duck tail stern for which these have in common, both with platforms for small sponsons were added for the paravane cranes giving ears to the stern. Pending individual research will decide how I add these.

Perhaps you can answer this question about the tow gear, were the paravanes attached to a single cable and with port and starboard versions made a "V"? Forward of the aft deck house is a very large cable reel which feeds through fairleads along the side of the deck house (somee stbd, some portside). How does the large winch connect to all this?

I believe that your "ship" was built in Bellingham in one of the boat works down in Fairhaven, now a tony district, but quite the opposite when I went to Grad School in that town. The model RR types seem to think that 1:45 (O Scale) is the smallest scale at which you can duplicate reality. In HO, still large for a ship model scale, some compromise becomes necessary. But of course smaller scales perhaps let the imagination and poor eyesight roam more.

I let the epoxy cure overnight and may get around (tuit) to some filling and sanding.

Cheers: Tom

Hull joined and beginning a fairing process. The 3D program is good for boxes, cones, cylinders etc, with which you can make many useful items. However it is NOT designed for making hulls so some post production adjustment is necessary. This is the first rounded bottom hull I am doing and won't stay put by itself. As a result will need to make a building cradle when we get to the fun part.

Cheers: Tom

For those wondering about nearly anything, it's not done yet.

Nice first Hull

_________________
Pascal

•Battleship Bretagne 3D: https://vu.fr/FvCY
•SS Delphine 3D: https://vu.fr/NeuO
•SS Nomadic 3D: https://vu.fr/tAyL
•USS Nokomis 3D: https://vu.fr/kntC
•USS Pamanset 3D: https://vu.fr/jXGQ

Tom,

The Cape was built in Bellingham in about 1960. I went aboard in April 1969 and the Navy decided to get rid of it in mid 1969 (it was practically useless as a minesweeper). It was decommissioned in about October 69 and sold to Johns Hopkins University for oceanographic research. So I was aboard for about six months.

The CO was a brand new Lieutenant, the XO was a JG surfer bum from SoCal and I was Ensign Fuzz straight out of Officer Candidate School (Engineering Officer, Supply Officer and 25 other official duties). We had a crew of 19 enlisted and 3 officers. We spent most of our time bolted to the pier in Long Beach, occasionally going out for "training cruises" (fishing expeditions) around Catalina Island. It was McHale's Navy!

For mine sweeping we could stream separate wires either port, starboard or both. There were two winch drums for the two cables. The lead ship towed a "V" and the following vessels followed behind the lead ships sweep to port or starboard (not both). This produced a wider sweep path, with the following ships "protected" by the lead ship's sweeps. The formation would sweep back and forth over an area until it was cleared. You can see some of this in "The Caine Mutiny" movie - always worth watching again!

Each sweep line consisted of a float ("pig") at the end of the line, with an "otter" some distance in front of the pig on the cable. The otter pulled the cable down from the float, and the distance between the otter and pig determined the sweep depth. Just behind the ship a "kite" or "depressor" attached to the cable pulled that end down to the same depth as the otter. So the cable pulled through the water more or less horizontal. At intervals between the kite and otter were placed cable cutters. These were loaded with a blank 30-06 cartridge that was triggered when the cutter encountered a mine cable, causing it to cut the cable.

I say the following ships were "protected" because if the lead ship did cut a mine loose it might pop up right in front of the next ship!

Our "main battery" was a 50 caliber machine gun mounted on the forward bulwarks. Lookouts on the top of the pilot house watched for loose mines and told the machine gunners where to shoot. Our "secondary battery" was me - with a BAR (Browning Automatic Rifle). I was on top of the pilot house and would be the first to start firing at the mine. The splashes would help the 50 cal crew spot the mine. We used to target practice with 50 gallon drums, firing the 50 cal in single shot mode to find the range and then opening up full automatic. This was a high pucker factor situation! Mines were designed to sink battleships with a very large explosive charge. If a tiny minesweeper struck one it would be more or less vaporized and blown into a cloud of splinters.

We also carried a "magtail" cable in the very large winch drum near the stern. This was a dual 1" diameter copper cable that was powered by the generators in the mine sweep generator room - I don't remember the voltage and amperage, but it was a LOT of Amps! The cables were streamed behind the ship. They had a thick buoyant insulating jacket around them. The longest cable had a bare "electrode" at the end. The other cable was several yards shorter, with another electrode at its end. The electric current flower through the water between the electrodes, creating a strong magnetic field that mimicked the field of a large ship. It would detonate magnetic mines that triggered from the changes in the Earth's magnetic field when a large metal ship passed overhead.

Our ship was made almost entirely of wood, and all metal parts were non-magnetic. This included the GMC diesels that were specially made of non-magnetic alloys - very expensive engines! We had four 6-71s ganged to drive the propeller, two pairs of 6-71s for the two minesweep generators, and one 4-71 for the ships service (120 VAC) generator.

A third type of mine sweeping apparatus was a large "thumper" acoustic device. It had two rubber diaphragms with a mechanical driver that caused the diaphragms to pulse to generate a pressure wave like a ship's hull and propellers passing overhead. This would detonate pressure sensitive mines. That thing had a massive construction designed to survive a mine explosion (hopefully). It was towed behind the ship at quite a distance, suspended below a pig.

Phil

_________________
A collision at sea will ruin your entire day. Aristotle

Phil:

That was good information. The large cable reel forward of the deckhouse was apparently for magnetic sweeping and the large winch (covered in photos) would then be a double reel type. One can build a better model and it's more interesting if one understands how it operates. The ship was festooned with davits stem to stern, no hawse pipes for anchor handling, the old fashioned stock anchors were hoisted over the side from their resting slot in the deck by a crane. Midships there are several small davits for hoisting spare paravanes and aft a paravane crane spotted on a small sponson on each side of the fantail.

I'll have to watch Caine Mutiny again to see if I can glean any details of the type of equipment, though it's a modern Destroyer, the equipment was of the same vintage. Watching and pulling stills form Away All Boats was useful in detailing Randall.

Cheers: Tom

Random musings: Why did the four stackers have four stacks instead of trunking uptakes together as in later ships? I think the answer lies in the way the boilers were fed a forced draft. I believe this harkens back to coal fired boilers where the boiler rooms were pressurized, with air locks for exit/entry. Trunking could cause a back flow from a boiler with no draft (ie. not operating). The four pipers were oil fired but retained the pressurized boiler rooms so a stack for each boiler. Marblehead and her ilk were also four stacker's as were some Japanese Light Cruisers so I am guessing a similar setup.

A disadvantage from the viewpoint of the black gang was any damage from a hit in the compartment could cause a back flash from the boilers.

Cheers: Tom

Been putzing away on the hull, added the zig zag waterways, bitts and chocks, props and shafts can be fitted but not installed, added sea chests and bilge keels. Some items produced and set aside for installation when the time arrives. Anchors, Radar, 26' MWB, 3" ready boxes and whatnot. Some a rescale to 144 form previous items and others pieces that Hank and I jointly developed or items he created for his 1:144 projects such as the bitts, chocks and the radar. These ships had very prominent prop guards and still head scratching as to the best way to achieve these.

The 4 pipers from which the DMS were derived were small ships, perhaps 1/2 the displacement of a Fletcher. Typical destroyer, somewhat cramped as most of the hull volume is taken up by machinery and fuel. Little wedges fore and aft for crew! As these were modified for escort and auxiliary duty one of the boiler rooms was removed, still allowing for 28-30 knots speed and more volume to increase the range and crew space. For escort duties 25 knots was considered sufficient. Even the DMS retained anti sub capability, sonar, depth charge racks and K guns. Being quite weight critical ships the armament varied depending on weapon availability. For the most part the 3" 50 was chosen to replace the 4" weapons as they allowed some dual purpose capability. The 40 mm Bofors was too heavy to add for medium AA so the 3" DP's and some 20 mm was considered the best compromise. Friedman (not Milton) has an interesting discussion as to how these compromises were arrived at. featuring at the last gasp pre war period, the 1.1" figured in the estimations, a weapon that proved a flop.

The first few conversions differed a little in detail and capability. The later conversions featured additional electrical generating capacity to allow for sweeping of magnetic mines and featured a large cable reel fwd of the aft deck house. The winch was a three holer and the stern had what appeared to be three rollers for the cables, sort of a big fishing trawler. I think I can glean enough detail from photos to construct a decent winch. I'll have to re screen Caine Mutiny to see if the later DMS's used the same winch and maybe I can pick up some additional detail of the sweep gear.

The adventure continues!

Tom

Just a question re. proper home movie etiquette -

Do you: 1) offer popcorn for anyone who might show up?
2) provide ample supplies of adult beverages for those who wish to share the experience?



Hank

ps - enjoyed the short historical narrative re. the DMS's & their service!!

_________________
HMS III
Mocksville, NC
BB62 vet 68-69

Builder's yard:
USS STODDARD (DD-566) 66-68 1:144, Various Lg Scale FC Directors
Finished:
USS NEW JERSEY (BB-62) 67-69 1:200
USN Sloop/Ship PEACOCK (1813) 1:48
ROYAL CAROLINE (1748) 1:47
AVS (1768) 1:48

Tom,

Search for minesweeper with Google. There are a lot of drawings and photos, including drawings showing the third drum on the winch for some type of cable guide or depressor to pull the cables down at the stern.

Phil

_________________
A collision at sea will ruin your entire day. Aristotle

Thanks Phil!

I saw some items in a drawing stowed on the top of the aft deck house right above the winch labeled depressors. The almost symbol like drawing didn't leave any ideas as to what these looked like.

I printed the clip shack (Which was Herman Wouk "cabin" when he first came aboard) with a 20 mm Orlikon tub above. Currently working on the aft deck house which has both a 3" 50 and two Orlikons on top. These are easier than the forward superstructure which is a bit complicated, complicated to the point that a lot of items will be needing of finish paint inside and out before assembly.

Currently I have assembled the armament, anchors and chain, chocks and bitts installed, paravanes (two pair which makes four) radar, clip shack, 26' MWB and have files to print from for many small items such as the pelorous, engine order telegraph, 20 mm ready boxes and whatnot. An advantage of printing is most of these items can be easily re scaled from 120 to 144.

I was hoping to not have to get to painting stuff this soon.

Tom

Tom,

I was wondering if the DMS had paravanes or had separate floats and kites?

Paravanes were use on many ships during WWII. They were streamed on cables that ran through a fixture at the bottom of the stem, and the paravanes pulled the cables outward in a "V" from the bow.

The minesweeper rig we had when I was in the Navy did not use paravanes, and was led out from roller chocks on the stern as I described earlier.

Paravanes were cylindrical torpedo shaped bodies with "wings" protruding from the sides. Our floats did not have the wings.

Phil

_________________
A collision at sea will ruin your entire day. Aristotle

Phil:

I was going to ask you about that, there is a good photo of "Perry" on page 53 of Friedman's Destroyer book ( I'll try to scan it) That could have "floats" on the fantail in the paravane racks. Just forward, stowed vertically is a box kite sort of device which I guess is to add downforce to the cable. Along the deckhouse are a line of small buoys, to mark a swept zone I'd guess.

Cheers: Tom

Stern view USS Perry, sweep gear.

The photo of the stern of the Perry and the other DNS show paravanes (according to the text) and kites. I don't see the "wings" on the paravanes that were on the paravanes carried on the Cleveland class ships.

I'm not sure when the paravanes became "pigs" like the floats we carried. But they were not called paravanes in the 1960s and 1970s.

It looks like the Perry had roller chocks on the centerline at the stern. The sweep cables were streamed through these.

Those sweeping davits came in handy for other things. We used them to troll for sharks, dumping a bit of fire fighting foam (made from beef blood) in the water to attract them. When we caught one we reeled it in with the winches. The sharks didn't care for this much and when we got them on deck they snapped at anything that came near. We finished them off with the spike on a fire ax to the head. We had a barbecue outfit on the fantail for cooking the shark steaks.

Phil

_________________
A collision at sea will ruin your entire day. Aristotle

Thanks Phil:

I agree that the items stowed in what the plans call Paravane racks are floats or "pigs". So I'll have to revise my delightful underwater flying paravanes. Dang they came out nicely! What do the depressors look like, are they kite like or some other shape. Plans show two stowed on top of the aft deckhouse.

At least the BAR is heavy enough that it "can be" shot full auto, at about 20 lbs. Full auto on the M14 turned out to not be a great idea. I have a friend who has both a BAR and a Nambu light MG. I asked if he had shot the Nambu and he said yes, but it tended to jam. Perhaps why it got captured? One not correct scene in Away All Boats was the mine episode where the ace shot has to hit the horn to set the mine off. The purpose of shooting was to puncture the case and have it sink.

Interesting sidelight on the foam!

Tom

Tom,

I don't remember anything we called a depressor. I found this definition for a modern depressor on line:

"Mine Sweeping Depressor NSN 1075-01-346-8103
Item Description

An item that is tear drop shaped, with a wing attached to the forward section and is used to depress the forward section of the sweep wire during mine sweeping operations."

So it is a pig with wings?

And then I found this description:

"MINE SWEEPIN AUXILIARY DEPRESSOR

1075-01-631-1486 A wedge shaped item, that is placed along the length of the sweep wire to keep it level during mine sweeping operations."

****

Actually, I think the kites were used for both the depressor just aft the stern and the otter that was below the float. The image below was from a web page about mine sweeping in WWII. Note that both the depressor and otter look the same, like a kite.

That makes sense because we had several kites. So I guess it was a depressor if it was close to the ship or an otter if it was below the float at the end of the cable. And I think one depressor was used when streaming port and starboard, so there would be no gaps between the two sweep wires astern of the ship. I think the center drum on the winch was used to raise and lower the depressor, while the outer drums spooled out the sweep cables.

But take that with a grain of salt. It has been 53 years since I observed a mine sweeping operation, and we did it only a few times while I was aboard. Our ship wasn't very good at it and sometimes got the sweep wire tangled with the mine cable. Fortunately we only saw inert training mines! Usually the mine squadron commander told us to just go away during sweeping training while the larger minesweepers did the work! As I said earlier, the MSIs were pretty useless. Only two were made for the Navy, but some were built for oceanographic research vessels.

Phil

_________________
A collision at sea will ruin your entire day. Aristotle

Thanks Phil:

In my net wanderings I saw that page. I had been wondering if two kites were used. Reference the Perry photo, On the aft of the deckhouse 01 level there are two smaller sort of scoop shaped items (like a snow shovel), are these too small to be depressors? A bit like fly fishing, some technique required!

Tom

Under the "Wah Hail" clause of model construction, I'm on my third aft deckhouse. Things would have been easier had I saved the design file in the right format. Somehow it escaped and got saved as an .STL, which did not allow me to make a few small necessary changes, so I had to go back to the beginning and re draw the whole thing. It's curing right now, but I think I like it so far. Working aft to forward as the bridge and galley superstructures are a bit complex and I haven't decided how to construct as yet. Weflack had an interesting way to do porthole glass. I may try (emphasis) turning down some plastic rod I have in the lathe and see if I can fit it in the open ports. The interior partitions were all re created as well as the interior doors, but I didn't leave any of the exterior WT doors open in the latest version. I am lucky to have already designed 3" 50 and 20 mm Orlikons in 1: 120 which only needed a small rescaling to 1:144. Same with the 20 mm ready boxes of which I had done a great deal for my earlier projects.

Tom

Tom,

I say those "scoop" things too. They looked something like venturis, but on the wrong end of the ship! Maybe they were kite/depressors. Don't know.

Phil

_________________
A collision at sea will ruin your entire day. Aristotle