Page 15 - updated 12 January 2008
Construction begins
September 2005
Propellers
Bronze, Steel, Plastic, or Brass? Pointed or Snub Hub?
The pre-1942-ish propellers were bronze (later steel due to material shortage). U 557 was laid down in 1940, so most likely had bronze props. The kit plastic would not do, so I bought Raboesch brass props: 20mm (3/4" or .79") A-type, Left and Right. Excellent quality, highly recommend for any naval project). 22mm seems more exact scale, but unavailable.
The appropriate Raboesch props are “snub hub”, but research photos (and the model) show the hubs as pointed. I used my benchtop drillpress as a vertical lathe (Dremel or hand drill in a vise would also do) and turned the snub-hubs to points. It’s not a perfect point, not as delicate as the actual boats, but I think better than plastic, especially when weathered. Thanks to Diane Paterson of SubCommittee for recommending I thin the blades for a scale look. It was a pain, but worth the effort. Thanks Diane! I weathered the props for months in saltwater, vinegar, and finally fresh water (the local high-chlorine content fresh water worked best), and have boosted the process with a little hydrochloric acid.
Pointy Hub
Wafer thin blades
Untarnished raw
Vents
The pre /41 hulls were approx 18mm thick*, or a scale size of .25mm. A bit thin and scary, so I angled the hole edges to get the illusion of uniform thinness.
Illusion of thin hull (scale)
*from Development of the U-boat in the Light of War Operations at Uboatwar.net
“Oil Canning” or Hull Buckle/Ripple
USN Gato class with oil canning
Boat hulls appear smooth from a distance, but up close, it’s obvious that ribs or “frames” support the sheet metal skin. It’s obvious because the metal is slightly indented between ribs, called “oil canning” (presumably because thin oil cans indent and deform when squeezed). This indentation happens naturally because there is much more support at the frames. Other factors turn up the intensity: slight ripples to metal, unevenness, differing expansion and contraction between the free metal and the fixed metal, etc.
Submarines add pressure from dives, and depth charging. Though the free-flood hull casing would not be affected by pressure (equal on both sides), all the other factors combine to make the ribs stand out even there. I added an oil can effect to U 557 to make the finished model seem more like a real boat. I cut masking tape into thin strips and laid out panels, then scraped each panel into a slight bowl shape using a very sharp #10 curved X-acto blade. I went through about five blades per side, and finished with a light sand using flexible nail files. I also added buckles and dents from minor collisions by scraping small but deeper lines and over-sanding them.
early hull plate work
Welds
The huge, uniform and square beads representing welds didn’t cut it for me, so I turned them into flatter, bumpy welds.
changing welds
Adding extra welds to my new “ribs”. Am masking with tape, then adding putty, roughing with a knife, removing tape, and sanding down a bit. The end effect should be subtle.
added welds - hint of buckled hull plates just visible
Emblems/Insignia
UPDATED 16 APRIL 06: Custom decals from ELS Trains (see Resources) look great. Tests indicate that the decals cannot handle overpainting with any sealers, acrylic or enamel! The decals dissolve! A coat of Future floor polish SHOULD fix this, and ELS recommends Microscale Flat or Gloss sealer.
Uflottille 1, U 557 emblem
Fun Stuff
Buy my submarine t-shirts and mugs at CafePress!
Just a small selection now, more to come (and open to suggestions).
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