The Ship Model Forum

That's really coming together for you! Well done!

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ICBM Address: 44:78N 063:63W

Ex RCN, HMC Ships Gatineau, Athabaskan, Charlottetown, St. John's, Montreal, Charlottetown, Summerside, Montreal.

Thanks! It is great to see it look more and more like the actual ship as the different stages of construction are completed.

I have very little information on detailed ramp structure from the prints that I have, so am using a combination of the GA plans, photos of the AMBASSADOR and its sister available online, and my memories from walking back and forth on the 1:1 ramp thousands of times during cargo operations over the years.

The GA plans provide a good profile and overall size of the ramp, as well as placement of the hinge axle.

One of the photos provides a good enough look at the bottom of the ramp to get the basic structure (six main support beams and various cross beams) and should allow me to create a pretty reasonable model of the ramp.

Another photo provides a partial glimpse of the transom area with the ramp open.

And my memories provide details that are not clear on any of the prints or photos, such as the fact that the ramp deck was textured, and also that there was a steel curb on either side of the ramp which prevented cargo from hitting the hydraulic rams that lifted the ramp, kept poorly-driven cargo from going over the side (at least until after they left the ramp) and (usually, but not always) prevented cargo from damaging the handrails.

The stern ramp will be built using various styrene shapes. The first step was to use the stern ramp portion of the GA plan to get a basic support beam shape. The ramp is built on shaped beams, and 5/16” styrene I-beam pieces were just the right size.

I first cut a paper template from a copy of the GA print to fit within the web of the 5/16 I-beam, and then used this paper template to scribe the shape on a thin brass sheet/ribbon. I rough-cut the shape and then filed the brass to a final shape, and drilled a hole in the proper place.

I cut the I-beam to length and clamped the brass template in place. I then used a very sharp x-acto blade to cut away appropriate parts of the I-beam web, and drilled the hinge hole in the proper place.

I then sanded and filed as necessary, and finally glued the flange down to the shaped web on either end.


I was pleasantly surprised at the results and made six stern ramp beams total-although I’m sure that the 3-D printer guys could turn out more accurate versions pretty quickly (without any sliced fingertips).

That is a nice way to get the flange on your custom shaped I beams!

It might take more time to do the CAD drawing, convert to STL files, set up a 3D printer and print than it took you to do it your way. And I doubt the results would have been any better.

Phil

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A collision at sea will ruin your entire day. Aristotle

Thanks, Phil.
I was very fortunate that a standard size and readily available styrene shape was just the right size for the support beams. Originally, I thought that I would have to build-up the beams from scratch and was not looking forward to it.

The deck of the ramp is made from thin (0.5mm) styrene sheet with diamond-plate texture. The actual texture was a herringbone pattern, but I could not find anything like that so went with the diamond plate pattern of roughly the same size visually-really just to show some sort of texture.

I cut a piece of the texture sheet to the right length and width, and had to be very careful doing so (it took me two tries) as the edges of the styrene sheeting were not necessarily straight or square. I then glued the two outboard support beams to the decking, using a steel rod/axle to line up the hinge ends.

I cut spacers from scrap plywood to provide even spacing between the beams and used these, along with the rod/axle to align the remaining beams for gluing.
After all six support beams were glued to the decking I temporarily taped the ramp in place and—Wow! That really captures the look, even without any cross beams yet, or the “flaps” at the extreme end where the ramp meets the dock.

I next wanted to glue in the crossbeams. Styrene 5/32 inch I-beams look like the right size, so I started by cutting a number of pieces to length to fit web-to-web and under the flange of the main support beams. Note that I test fit and filed each individual piece to get a good, snug fit to make sure that I had maximum glued area for each.

I made a jig to help keep these pieces in a straight line when gluing, once again using a bit of scrap plywood (I held on to lots of pieces after making the keel and frames). I also marked the appropriate spacing on sheets of paper and taped them down to a cutting board so that I could lay the ramp down and keep everything lined up.

I glued the cross beams at the appropriate places and was happy with the results. The cross beams at the extreme ends will be slightly different as the support beam shape is shallower (flap end) and I need to be careful of the hinge clearance (hinge end).



One thing I would do differently would be to use a heavier piece of styrene sheet for the ramp deck and glue the texture piece to that. I think that the 0.5mm sheet was too thin, and had problems with the deck curving/cupping after being glued to the support beams. You can see that many of the photos show weights in place to try to flatten it. I did not want to start all over and also hoped that the crossbeams would help to keep the ramp flat once glued in place. This seems to have worked (so far!) but I will keep an eye on it over time.

beautiful and crisp job on that stern ramp!

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The merchant shipyard

Thanks, Neptune.

It has been a fun sub-project and so far has turned out as well as I could have hoped.

I placed the remaining sets of cross beams at either end of the ramp.

From the under-ramp photo it appears that there is a piece that runs across the ramp near the hinge that is flush with or running across the web of the main support beams. This should not be too difficult to do, but I am going to wait until I have figured out exactly how I will fit the ramp to the hull. I plan to make it so that the ramp can open (manually) and need to be sure that the hinges on the hull are clear of any ramp structure and the ramp can open as needed.

I am still debating whether to complete the upper side of the ramp now (curbs, lifting pads and railings) as well as the "flippers" at the extreme outboard end or wait closer to when it will be installed. I may leave it for now so that I have a fairly simple change-of-pace project to turn to as I get the hull ready for the fibreglass coat, and the steps that follow.

I'm sanding the hull to prepare it for fiberglassing. I'm slowly making progress, but really nothing to take a picture of. Meanwhile, here is a picture of the AMBASSADOR and another of its sister the DIPLOMAT (later changed to SENATOR) that I recently found online.

These look like they were taken on delivery or shortly afterwards. The AMBASSADOR looked pretty much like this when I joined. Shortly after I joined the "CCT" logo was painted over on the side and the stack, and then the stack painted red.

What is interesting to me as a modeler is how these two sister ships, built at roughly the same time, had different paint schemes for underwater hull, deck machinery (and later) decks.

What is also interesting is that the AMBASSADOR (as built) differs from the Painting Plan blue print (which I have) in what will be very obvious, especially in a model: the Plan calls for red hull paint under the waterline, and the actual ship (even as early as this photo) had grey hull paint below the waterline.





There's another, quite striking difference between the General Arrangement prints and the actual ships (that I believe is just a mistake on the GA print) but I'll wait until I am building the superstructure to show the difference.

Why wait? Since I'm talking about the differences between plans and as-built, may as well show the most glaring example--something that goes far beyond deviations from the Painting Plan.

Here's a photo of the superstructure from the GA plan that I had copied from one we carried on the ship decades ago. Compare the port side of the superstructure under the bridge wing to the photos of the ships as actually built. As you can see, the GA plans show the body of the superstructure extended outboard on the port side from the No 1 superstructure deck level all the way up to the bridge wing. The actual ships had a single level space at the No 1. Sup. level that covered the ladderwell (stairs) coming up from the A deck and also covered the port side access to the interior of the superstructure. The bridge wings and superstructure look much more symmetrical as built. (I marked my copy of the GA plan with pencil X's.)

I have no idea why there is such an obvious difference between the GA plans and as-built, but the digital copy of the GA plans provided by the builder (which is slightly different from the GA plans that I copied) show the same un-balanced super structure.

The deck plan views of the superstructure decks on the GA plans show this as a void space.

Not sure if it was a drafting error, but I imagine that the as-built structure used slightly less steel. Just a bit of a curiosity, and goes to show that there can be a significant difference between ship plans and how the ship was actually built.

I have seen a lot of differences between the General Arrangement plans (Booklet of General Plans) for US Navy ships and the as-built final products.

The GA plans usually were created from the initial blueprints before construction started. As such they were more of a wish list for planning and selling the vessels than a real plan. The actual plans were often changed in the shipyards where they had to figure out how to build the ships. The final blueprints usually list a series of design changes that were made during construction, and these don't appear in the Booklet of General Plans.

Changes were inevitable, especially before Computer Aided Drafting (CAD). I recall a story from a CWO bosun who served on the commissioning crew for the USS George Washington, the US Navy's first ballistic missile submarine. He told how a draftsman had accidentally drawn a line for a bulkhead across a pipe. The shipyard welded pipes to both sides of the bulkhead - as if they were hand rails. But the pipe was supposed to carry something (air, water, etc.) and there was no hole in the bulkhead. In another case one blueprint showed a pipe running along the overhead, and another drawing showed the installation of a valve on a different pipe on the overhead. The shipyard built the ship as the drawings showed, but the pipe passed through a hand wheel for the valve, between the spokes of the wheel, so the valve could not be operated! Changes were made before the ship put to sea.

Phil

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A collision at sea will ruin your entire day. Aristotle

I am sanding the hull in preparation for fiberglassing to ultimately make it waterproof and stronger. No real pictures to show progress, but it is satisfying to smooth out the slight bumps and ridges in the planks and see how the final, fair hull shape will be. Definitely have a few spots that will take some filler, also.

I noticed that I was having difficulty smoothing a few of the ridged (“proud”) planks, as when I checked after sanding there was still a noticeable height difference between the plank and its neighbors. I figured out that this was happening between frames with some especially flexible planks, and that the plank was flexing inward when the sanding block passed over so that the sandpaper could not truly do its job. I brushed a little bit of wood glue in the inside of the hull around the planks in question and sanded again after the glue dried. This did the trick as the glue held the planks rigidly to the adjacent planks and the sandpaper could get full purchase.

Probably nothing new for the old hands at this sort of hull building but thought that I would pass it on.

Many years a go I discovered that painting the interior of a planked hull with epoxy paint (the kind aircraft modelers use to seal engine mounts so they won't soak up fuel) bonded everything together very tightly. Planks were bonded to each other and to the frames.

This prevents eventual cracking and separation of planks over time.

Phil

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A collision at sea will ruin your entire day. Aristotle

Thanks, Phil. I can see how this would be helpful even in display models.

A modeler that I know who has built many beautiful scale R/C warships coats the interior of his hulls also, to keep any spills or other water that might get in from soaking into the hull structure and causing swelling or other problems. I plan to do the same but intend to epoxy/glass the exterior first.