There was a post some time ago here on the HAMB that really perked my interest the post was about acid etching at home. http://www.jalopyjournal.com/forum/showthread.php?t=136610 In that post along with several examples of etched badges were links to an article that described the process in greater detail. http://www.gasenginemagazine.com/archive/0403/0403_feature1.html I recently completed a little project for Ryan and thought it would be nice to add a little something extra so I decided to make a custom brass tag for it using info from the above articles. Ryan thought it would make a nice tech piece so below are the details. First, come up with a design. In my case I had a specific area I wanted the badge to go that dictated the shape so I traced the area including mounting holes and scanned that tracing so I could do the design in illustrator. Designs should be done in black and white. Areas that are white will eventually be eaten away and filled with paint and areas that are black will be bare metal I did my design the way I wanted it to look in its finished state. When the design was completed I had to mirror the image and reverse the colors for the transfer process. Next is to transfer the design to the transfer paper. This process, which has its routs in custom circuit board design calls for the use of a special transfer paper called PNP blue. I ordered my paper from a company online. The paper is designed to be printed on a laser printer and comes in standard letter size 8/12 x 11. Its a good idea to fill your page with as many designs as you can get on the page because chances are it will take a few transfers to get a good usable one. Determine what side of the paper your printer prints on and load the paper with the chalky blue side as the side to print and let her rip. Once printed, carefully cut out the designs. Next step is to prepare the bras to be etched. Cut out a corresponding piece of brass slightly larger than the design you intend to etch. The surface to be etched should be thoroughly cleaned and free from grease or oil, which could hinder the etching process. The opposite side should be protected from the etchent solution. There are several options to protect the backside. The easiest is to cover the back with tape, I have used masking tape as well as clear packing tape, both work but etchant has a tendency to work its way in around the edges especially with the masking tape. If the design is smaller than the brass its usually ok if there is a small compromise around the edges. A better way would be to apply a thin coat of paint to the back. Once the brass has been prepared its time to actually transfer the design to the brass. Lay down a couple of paper towels and place the bras on top. Place the trimmed PNP on the brass and tape it down to keep it from shifting. Add another layer of paper towels on top. The transfer process is done using heat. Smaller designs are easily transferred using an iron set on high. I have found that holding the iron down under pressure for about 25 or seconds followed by gently sliding the iron back and forth with light pressure for an additional 30 or so seconds works. At this point carefully take the hot brass to the sink and run water over it to cool it down. When its cool peel the PNP back to expose the transfer. If there are small areas that didnt transfer you can fill them using a little spray paint on the tip of a fine brush. If the transfer failed miserably clean the part using solvent and start over. This step is one of the most challenging parts of the process. It takes a little practice to get a good transfer, once you get the transfer process down the rest is easy. Once you have a good transfer, mask off the remaining bare areas with tape and create a little handle with a loop of tape. The etching part of the process is done using a chemical called ferric chloride. Ferric chloride can be found at radio shack under the guise of PCB etchant or is widely available on line. I have found that the etching process is greatly enhanced by the use of heat and agitation. I bought a couple of small glass cooking pans with snap on lids, which are convenient to both etch in and store the etching solution. Place the brass in the glass container on the stove with the tape handle sticking up and fill it with enough etching solution to cover the brass by a ¼ inch. I jerry-rigged a set up to keep the temperature from getting too hot. It may take some experimenting and creativity to keep the solution from burning. Its probably obvious but care should be taken to prevent a fire and to regulate fumes. If youre stove is off limits this process can be done cold but will take longer. I have found that to get a good deep etch its best to leave the part in the solution for at least an hour. Agitating as often as possible will help aid etching. I usually agitate the solution over the brass by rocking the glass container or lifting and dropping the brass by the tape handle. To check progress lift the brass out of the solution. When it looks deep enough pull the part out and rinse it. Although ferric chloride wont burn your skin it will stain it and anything it comes in contact with it will also eat / stain metal so it may not be advisable to do this process or rinse it in an area you care about. Once the part has finished etching and has been rinsed you can remove the tape and trim the brass / drill any mounting holes. I usually design a border into the part that can be used as a cutting guide. When the badge has been trimmed coat the whole front side with paint. When the paint has dried use a sanding block with some fine wet dry paper and wet sand the raised surface leaving the paint in the recess. The resulting part is a nice shiny new custom badge. The applications for this are almost limitless. With a little practice, very nice and professional looking badges can be done at home with minimal investment.