The simplest answer is to the make them like the ones you see on real cars. However, that is way easier said than done. I have and have used many different photoetch wiper sets, including the ones you picture above, because I think that the single least realistic part of almost every plastic car kit is the wipers. With very few exceptions, kit wipers look out of scale and utterly unconvincing without major modifications. That said, I'll try to add some helpful suggestions and illustrations. (I don't know how many pictures the forum will allow per response so I'll probably have to add several entries.)
First off, not to badmouth Detail Master, but I'd get rid of their wiper sets. The second ones simply don't look realistic and the first are so hard to bend you'll end up in a mental hospital trying to get them to work (that goes both for the arms, which are absolutely impossible to bend partly due to the thickness of the metal and partly because of the very slim sides to be bent, and the blades, which are impossible to get to line up correctly after folding). The MCG set is pretty great but suitable only for a select period of motor vehicle; if you only build cars of a certain vintage then you are ready to go.
I have sets from Hobby Design, Crazy Modeler, Good Smile Racing, KA Models, some generic no-name sets, and more. Some are better than others, but all of these actually work reasonably well, that is, they bend easily and you can glue the things together without tearing out all your hair in the process. I highly recommend the Good Smile Racing set A for vintage 1950s and 1960s cars. A couple from Crazy Modeler:
In addition to the above there are lots of pe detail sets for specific cars that include wipers. These are usually pretty easy to work with because they are designed for a particular kit (duh!) and so don't require a lot of manipulation to get them to look right on the model.
So, what's my procedure? I select the wipers I want to use, or that come with a detail set, and then use this tool to cut them from the fret frame:
You'll need some kind of bending tool, also, to get the things in the right shape. I use Tamiya's short bending pliers, a generic pair of flat bladed pliers, and various kinds of tweezers (for the blades). Bend them till they look right. The fold lines VERY RARELY GO ON THE INSIDE. Most wipers are etched with detail that appears on the same side as the fold lines so that tells you which side is UP. When you like the shape your wipers are in, then it is time to glue the arm to the blade. This will take you approximately 42,650 attempts before you are comfortable with it. A huge pain, it is. I usually use reverse tweezers to hold the arm is such a way that you can set the whole thing down on your workbench while the glue dries. I also frequently use reversed miniature clothespins to hold them (Do you know what these are? I'm not sure I have a picture to illustrate.) You should align the arm and blade so you know exactly how they will go together before you try it with any glue. A tiny bit of CA is the best choice for this; other adhesives are not strong enough or are too visible. So, use whatever method you find best to finish the job. I usually apply a tiny bit of the CA to either the arm or the blade, whichever seems the better choice, and then hold them together briefly before setting them down to completely dry. Tedious and nerve-racking, but necessary for decent looking realistic wipers.
Afterward, you can prime and paint them with your favorite primer and paint. Always with an airbrush if you want them to look in scale and not all goopy with paint.
Another possibly super-helpful tip: It is possible to use the base of the kit wipers in conjunction with photoetch arms. Take the kit wipers and use a sharp cutting tool to lop off everything above the base that attaches to the body. After you've bent your wiper arms, modify the base as needed to fit inside the folded parts and glue with whatever adhesive you prefer. Once this is dry you can test fit it to the model and adjust the bend of the wiper arm to fit snugly against the windshield.
I think that is all I have to add. Feel free to ask questions and whatnot. I'm adding a gallery of photos that illustrate the beauty of photoetch wipers and I hope the images are reasonably clear. i may add some annotation to the pictures because some of the wipers look better than others and I'd like to point out what I find to be particularly successful uses of pe wipers.
Edited by Chillyb1, 14 February 2013 - 11:31 AM.