The Ship Model Forum

The next project will be the last APA and AKA in this "campaign". They were in my opinion the worst auxiliary ship designs made by the USN in WWII, therefore I have to build them.
Anyone interested in puzzles is free to guess their identity, the clue is that initial work will be done on both hulls at the same time.

The only candidates that occur to me are Artemis AKA-21 and Gilliam APA-57 classes. I always thought these rather good looking though. Oh well...

Looking forward to seeing any new build(s).

Mac

Fantastic work on AP-130 man! I love their design and a build is on my list. At least now I can reference yours

Bob, Cliffy thanks.

Mac, you are correct. I also agree that they were attractive ships. Their design constraints of small size, shallow draft and split propulsion plant meant they could not carry much in the way of cargo, troops or boats. The USN kept NONE in service as AKAs or APAs post war. Most of the APAs (new ships !!!) were used as targets at Bikini (commercial shippers did not want them either).

I too was struck by their small size, particularly after building the Loose Cannon 1/700 model and comparing it to my other builds. They have the look of a much larger ship. Some further research at http://www.shipscribe.com/usnaux/frameset.html confirmed they really were small and some of the reasoning for their design.

The use of so many of the APAs, most only about a year old, in the nuclear bomb tests was also striking. Your conclusions appear correct. The similar looking, but much larger, General John Pope (AP-110) and Admiral W. S. Benson (AP-120) classes seem to have been far more popular with both the Services and commercial owners.

Anyway, gives the rest of us more opportunities to admire your exceptional work.

Best regards,

Mac

The next builds will be a Gilliam class APA and an Artemis class AKA. Thirty two of each were built and they can be considered close cousins in that they shared the same hull, machinery and midship superstructure. They were attractive ships, liner like in general appearance, especially the APA (pic-6).

I have come to the conclusion that these were the "worst" Auxiliaries designed by the USN in WWII simply because they were too small to bring a useful load of troops, cargo and boats to the beach. This conclusion is supported by the fact that none of the 64 ships were retained by the USN as APAs or AKAs after WWII. Most of the APAs were used as targets during the Bikini Atom bomb tests. Most large organizations have a tendency to bury their mistakes, in this case the USN atomized theirs.

What is interesting is that my perceived primary flaw was also their primary design consideration. Per Friedman, Admiral King was upset about transport losses incurred during the Guadalcanal and North Africa invasions. These losses were primarily the large WWI era cargo/transport conversions. King concluded that these and future losses should be made up with very small ships on a 2 for 1 basis, the loss of an individual small ship would not be as consequential. The design criteria then became small size, shallow draft, and a split propulsion plant. The USN got what it asked for. Meanwhile the scope of transport needs rose well above what was envisioned at the end of 1942 and by necessity the USN added APAs and AKAs in large numbers based primarily on Maritime Commission C-2 hulls. These proved much more successful, see table below (data from Friedman).

....................Hull Type.....LOA...LWL...Bm...Dft......Light.....Full......Crew..........Troops

Gilliam Class...S4-SE2-BD1....426'...400'....58'..15'6"...4247 T...7081 T...21/19/316.....29/975

Haskell Class...VC2-S-AP5.....455'...436'....62'..22'9"...6873 T..10680 T...28/23/451....86/1510

........................LCVP...LCM.......5"....40mm...20mm...Fuel-Gal....Radius@15kt....Gal/kt *

Gilliam Class..........12.......0.........1......4 x II.......10......406000..........5256.............77

Haskell Class..........19.......2.........1.....4 x II........10......328000.........7200..............46
....................................................1 x IV

* this calculation is a stretch (fuel capacity/range) but I think illustrative.

It is my post above as "guest", login timed out.

On to the model

Pic 1 hull blanks

Pic 2 APA foreground (extra deck level aft), AKA in background

Pic 3 & 4 more hull

Pic 5 APA, major parts roughed out

Pic 6 a Gilliam class APA

Cross-link compliments

A post on davits, the first on parts, the second on assembly.

Pic 1 Before parts are made, dimensions need to be known. The width of the boat deck is major, usually it is 12' (.40"), while the LCVP was 10'10" (.37") wide, not a lot of wiggle room. Both the angle davit arm support and the upper boat support are located by holes drilled just outboard of the deck-house bulkhead. I trace the outline of the pinned deck-house on the boat deck, this becomes my "do not cross" line. Add longitudinal locators, punch the hole location and go to the drill press.

Pic 2 Angled davit arm support, the "trickiest" part. The graph paper is decimal inch if you want dimensions. Cut 2" blanks from .032"brass, bend around a 1/4" drill to get the curve to the 30 degree angle. Mark the second bend point (green mark), you will notice that it is "short" - that is because the bend takes length, which has to be "fudged". Straighten the part so the angles are correct and it is on one plane (two bends normally yield a part that is not flat). Cut off excess (red mark) and grind the short end until red disappears (this establishes the height of the part, the long end is inserted in a hole where it will not touch bottom).

Pic 3 Upper boat support, .028" florist wire (get at any craft shop), two bends around a pliers that is .033" wide. This part is the most sensitive for width, it has to fit in a .040" space yet go around a .37" boat.

Pic 4 Davit arm support sides. Made from a primed .004" thick clear plastic page protector. The tracing pattern is 30 degrees down on both sides of center, crowned with the same 1/4" dia curve that the post was bent around. Length of the part is not an issue, just make it oversize (it will be trimmed to length after it is glued to the wire support). Vertical spacing part to part is 2 mm (.080"). this gives an actual width of 0.067" (the angle causes the difference). You can spit out parts as fast as you can cut one inch with scissors and the set up easy.

Pic 5 davit arm, .020"styrene. The trick is to draw a set of box grids .30" wide and .47" high. The angle of the base line is 30 degrees going to the right. Where that line ends go 30 degrees up to the left side of the box. The upper portion of the arm is .060"wide at the top and .180"wide at the bottom (measured from left side of box). Four chop cuts with the wide blade, circular recess at the bottom with a .200" dia paper punch. Cut a little "V" notch at the top of the arm. The nice thing about using a grid box is that you only have to measure and mark at the beginning and end of both rows and columns, the marks in between can be made off a straight edge. Even though it looks complicated at first view, after making hundreds, the arm is much easier than the wire support.

Pic 6 Horizontal beam, .005" brass 1.38" x .20". The centerline distance between arm supports is 1.40", 1.38" allows for the wire thickness. I make a 90 degree bend with the paperclip and then pliers. The part is then folded over a .018" thick ruler. "Ironing" with smooth pliers while still on the ruler gives a nice finish. The lift blocks are scrap PE trimmings.

J'adore ...

Davits - assembly - SORTING, Placed 8 angle supports on one side of the ship just to compare and the results were rather ugly. Proceeded to switch and match until both ships had 4 supports per side that looked "good" in relation to one another - see pic 1. Pic 2 has a more critical view of both the angle supports and the upper boat supports, the easier to make green upper boat supports show a better match.

Pic 3 Gluing the sides to the angled davit arm support. Again SORT the sides until there are 8 pieces for both port and starboard that match well. Glue ONE SIDE AT A TIME to allow easy trimming to length. To properly locate the side, trace the ID of the support with a probe to push the side up and out to form a channel for the davit arm. Locators for trimming are the ground end of the short leg and the curve at top of the long leg. Glue and trim the second side.

Pic 4 Sub-assemblies ready for painting.

Sir,

Thank you for an excellent two part tutorial. Your illustrated lesson answered my questions most thoroughly. I, and I'm certain others, appreciate your showing so many "tricks of the trade". Your earlier explanation of creating the hull was very useful.

One thought did immediately occur; mark the angled davit arm support on a block of wood and construct a jig with two nails locating the bends for the brass wire. Having seen some of your methodology, I suspect you either considered or tried this and found it unsatisfactory. Your thoughts please? Also, did you complete any of the LSTs you did hulls for some time back? My father served aboard LST 586 and I would like to try and build a model of her. He, before his passing, and I worked on the old Lindberg kit but I think I can build something better (hence the hull and Welin davits interest).

Thanks again for all your help and I promise not to bother you (for some time anyway) more.

Best Regards,

Mac

Mac, thanks - no problem with "bother".

The problem with the jig is that the hard brass rod will always "spring back" an appreciable amount, you always have to over-bend to get what you want (there is a metallurgical explanation - you always return to "0" following the angle set by the modulus of elasticity on the stress/strain curve, even after plastic deformation).

Have not done anything with the LSTs, have to develop a "green" palette and have plenty of "blues" in the stash. HNSA has LST plans online, go for it. I would start with one hull which you set in your mind to be scrapped, just to develop techniques and confidence. This will guarantee a plastic kit will come out.

Hello Jim

beautiful demonstration of knowledge to make and a good grasp technical various
thank's for sharing
best
Nicolas

APA-58 USS Appling is finished. Pic 1 & 2 are the ship and the model. Pic 3 & 4 are comparison shots of the Appling with the Kenton, a Haskell class APA.

Hello Jim

how to tell you ...... I am in awe of your work !this is simply beautiful
I do everything to have a day in your level in the sctrach......but, the way is long
bravo again
regards
Nicolas

awesome work Jim.

Question, what is your preferred type of wood.
I have never used wood only styrene to produce my scratch builds but have always wanted to have a go.

Roy

Nicolas, thanks again.

Roy, I use milled poplar that I get from Lowe's ( a US home improvement chain). It comes 4" wide (enough for all USN WWII ships) and in an assortment of thicknesses.

For hulls I sandwich with carpenters glue (in the US a water based, yellow, thick glue for unpainted wood. VERY strong) 2 or 3 pieces of whatever thickness gives me the height I need.

For superstructures I layer .250" wood with .030" styrene sheet. This gives me a deck to deck spacing of .280" which converts to a prototype 8.17'.

Poplar advantages. Inexpensive, milled, clear, sands well.

Poplar disadvantages. A tendency to chip/splinter at exit of drilled holes and scroll saw cuts (but that is what Bondo is for).

I prefer poplar to basswood (widely used for modeling) because it is finer grained and harder. A finished hull made from basswood will dent if you look at it too hard.

Another pair of winners Jim! So what's next?

Hey Jim, have you thought of making the ship from the film Away All Boats?

That'd make a slick diorama...

Hey Jim, have you thought of making the ship from the film Away All Boats?

You might want to look at page 5 of this thread. Actually, if you're interested in the craftsmanship, the ships, or both, this is worth reading from the beginning.

Mac