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Answer to Pop Quiz: What is the element involved in the manufacturing of some modern kit resins that won't allow it to cure more than 87-91%? Formaldehyde. It also tends to eat and rust piano wire or white metal.
Since this is a 'How To class' lets keep it basic. First sets of WWI aircraft PE (photo etch) was Harry Woodman's sets that are still available under the Fotocut label at Rosemont Hobbies I believe. Essentially there are two types, bare metal brass or bright nickel coated metal. The reason for the nickel coating is that while it does provide strength it also tends to interfere with any bending or forming process. Now to start;
Most photo etch comes in a small clear poly bag and card backing. This is not just for looks. Keep them for later.
1. Bare metal photo etch frets , usually come in brass as its softer than most metals, uniform in color (from a marketing point of view) and easy to purchase. The thinner the fret or its pieces the easier to bend and form. To soften it further 'pass' it through a candle flame until dicoloured. Photo etch is a by-product of model rail road hobbyists. To get a good surface to paint on they gave us 'Hobby Black' or 'Blackinit' a mild acid that etches the surface of the pieces to allow good primer or paint adherance to the surfaces. After immersion in the blacken solution then wait about 15-30 seconds or until the fret turns a dark carmel brown. Wash or submerge the fret in clean water. Place on a paper towel and pat dry. Then to add depth or texture to a piece you can used primer, hobby putty, gel super glue, scrap plastic or paint pigment (that thick stuff at the bottom of your paint tin/jar.)
The nickel coated metal frets need to have the nickel coating roughed up for paint adherance in most cases. Again 'pass' it through an open flame until discoloured. Most nickel coated etch metal is brass, copper or pot metal. No need to blacken the fret as the burned nickel acts as a primer and gives the your applied coating a good surface to bite into.
Generally speaking after blackening and drying the intact fret paint the individual pieces as needed. The when dry, slip the intact fret back in the bag. With a flat section of quarter inch plywood use your Xacto/ rador knife with a new blade to cut through the clear bag to the individual pieces and their attachment point to the fret framework. I use inexpensive locking medical clamps to hold an individual piece when working with it. Scrap of any unwanted paint so the piece will adhere well when glued inplace.
Bending or folding a piece is best done after removal from the fret of course. Some pieces you'll want to bend and shape then paint. Usually this means the pilot's seat and backing or lap and shoulder harness' as an example.
Control horns are very easy, but if you rely on unaided eyesight your in for trouble. Always use an optivisor. Drill your anchor holes and glue in place with thin superglue then when dry add a bead of gel type superglue to the base of the horn on either side. Then let that dry. (You can be moving on to other control horns while that one is drying. When set completely, add your rigging material. If the rigging needs anchor holes predrill them while the piece is on the fret.
Some of you have expressed some mild trepidation as to inserting a drill bit into the surface of you model. To get over this take and old wreck or kit that you can stand to experiment with like a paint hulk or even just flat stock and experiment with the technique. Nothing ventured nothing gained.
Questions?
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