On The Slipway

Category: General (page 4 of 4)

Sounding Machine

A sounding machine is a device for (as far as I know) measuring the water depth. I wouldn’t have noticed it if it weren’t for these two photographs (from the HMS Hood site). . The “Anatomy of the ship: the flower-class corvette Agassiz” has an excellent drawing of the Kelvin Sounding Device Mk Iv on page 16, but it’s a different type. Good enough for basic dimensions and for some detail.

Fortunately, around the time Hood was built, several of the Imperial Japanese Navy ships were built in Britain and carried the same equipment. The photograph at left was found on the net, taken in a Japanese museum. The picture at right is from the book “Grand Prix Shuppan: Anatomy of Japanese Battleships 2”. From these two images I made a small photo etch design in Autocad.

At left, the photoetch parts are shown. I added some disks to simulate the detail prior to cutting the parts loose, making it easier to handle them. The lower picture shows the finished parts. Cute! The picture at right indicates where the sounding devices where fitted to HMS Hood’s bridge structure. That is, if they were still fitted in 1941?

Degaussing Cable

The degaussing cable proved to be a rather labour-intensive piece of detail. As you need over 2 meters for such a large model, you need a quick way to produce a lot of it fast. The cable was added to the etch set, but I wasn’t happy about the result at all. Also, from photographs of the ship, it is apparent that the cable was added sloppily, not at all as a straight and neat cable. So, scratchbuilding then!

I needed strip, a lot of strip, and with a consistent thickness. So, a short exercise in cutting lots of strip.

I start with some Evergreen strips with a smaller strip glued on to it (left). This smaller strip has the correct thickness for the to-be-cut strips. I put it to the plastic sheet (center) and then align the ruler (right). This gives you a pretty consistent strip thickness. I could have bought readily-available pre-cut strip, that is, if it were readily available and it isn’t.

This is the gluing jig. Lots of plastic strip to help me with aligning all the parts for the cable.

Here ten new strips of degaussing cable are taped to the jig.

And here are, err, lots of smaller strips taped to the mould as well. They have already been glued. I tried a few types of glue, some gave a very brittle bond.

The smaller strips were made from 0.13mm Evergreen sheet, that is, very very thin. I marked the sheet with a red marker before cutting, so I knew which side should have been up. I also added the line to the other side, so that you can avoid glueing the strip without it being rotated along its longitudinal axis. Pretty difficult to see if lt goes well with all these strips so a bit of color helps.

Once all the strips are glued in place, I cut the main parts loose.

I used two tweezers to fold all the small strips: one for holding it at the junction, the other for folding. At this point, I started to loose a lot of strips (breaking or coming loose). Next, the excess strip was trimmed by pressing it down with a ruler just at the junction and then giving it a quick cut with a new and sharp blade.

Then it was sanded down and repaired when necessary. If the reparation was too much work, I just cut out a section.

Before adding the degaussing cable to the model, I first had to add a small ridge on the exact side of the deck. These parts were very helpful in clamping a strip at that exact edge before fixing it with glue.

Hmm, that looks like the real thing, much better than etched cable to my surprise. Note how sloppy the real cable is and that the upper cable is slightly thinner than the other. And please don’t note that the portholes aren’t really where they should be. I’m not going to fix that…

I only had 7 sets to build, so doing it while being drunk alleviates the effort. I had all the cable I needed, but left one set on the table and I have cats. Guess what happened? I’d never thought they would do that…

Capstans

The capstans are based on the drawings in Ross Watton’s “Anatomy of the Ship: the battleship Warspite”. I used to think this volume didn’t really contain a lot of useful drawings, but that is clearly wrong.

Being rather circular, I relied on my circle cutter by Olfa. That tool is hardly worth throwing away, but can be used with a few modifications. As you can see, I cut away some meat from the black plastic and glued the knife to the bolt that is supposed to keep the knife down. This way you make make smaller circles. The base of the part is the etched top. Spokes were added using the drawing at bottom left, eventually filled out with 15 strips. 

 All the ingredients for the forward capstan. I forgot to etch out the center for the bottom part, using the punch and die set to rectify the situation.

Forward and aft capstan, finished. Perhaps I”ll post better pics later…

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