Simulating plating in 1/700 scale

are you able to see weld lines at a 1/700 scale? a half inch wide weld at 1/700 is .0007 of an inch.

I'm not sure exactly how the plating of Liberty ships worked, but in many welded-hull (and, for that matter, rivetted-hull) ships the plates are laid in strakes that overlap each other at the edges.  The strakes are commonly called "inners" and "outers," and the edges can be pretty prominent in photos - depending on the angle of the light.  Few small-scale modelers try to reproduce the butt joints between individual plates in a strake, but the edges of the strakes are worth thinking about.  The strakes generally are pretty wide.  On a waterline model of a typical WWII destroyer, for example, three strakes (two "outers" and one "inner") are likely to be visible at the bow.  The line between the "inner" and the lower "outer" sweeps gently downward and disappears under the water somewhat forward of amidships.

Here's a trick you might want to try.  Paint the hull the base color and let it dry thoroughly.  Determine where the horizontal line between an "inner" and "outer" strake is.  Lay down a strip of masking tape with its lower edge on that line.  Mix up some paint in a shade very slightly lighter than the base coat.  Using a flat, somewhat stiff brush, dry-brush it in vertical strokes, starting on the masking tape and feathering out to nothing below it.  Peel off the masking tape.  You now have a weathered hull, with a barely perceptible line indicating the edge of the plating strake.  An occasional rust stain applied the same way will make the illusion more convincing.

Another approach is to cut and fit a piece of masking tape carefully so it covers up the "inner" strake, and spray several thick coats of paint on the rest of the hull.  If you're careful (and lucky), when the tape is peeled off, the thickness of the paint will do a good job of representing the "outers."  I haven't tried that one; I guess I have a knee-jerk reaction against deliberately applying paint in thick coats.  But I've seen that technique used pretty effectively.

In any case, the key is to keep it subtle.  If the observer has to look really carefully at the model, from a distance of a few inches, in order to see the "plating," you've got it about right.

Hope that helps a little. 

I wouldn't bother on a 1/700 Liberty since it's just weld beads and they don't show that much in photos. If you really must do it I'd use stretched sprue and get it as fine as you can.

Were you doing a ship lapped plates there are several methods ranging from masking plates and applying several layers of heavy primer to masking plates and feathering in Evercoat two part putty.