I made a custom machine badge for a bandsaw that I restored. The badge was made from a section of old discarded license plate. The same process could be used on brass, copper, stainless steel, etc.
- metal plate (I used a license plate)
- ferric chloride https://amzn.to/2H61nHJ
- plastic/glass bowl
- vinyl decal (see other methods below**)
- transfer tape (I used Glad Press-n-seal and Packing tape) https://amzn.to/2HaBquH
- paint / brush
- sandpaper (fine - 800 grit or higher)
- nitrile gloves https://amzn.to/2JQTVCl
- stiff bristled brush
- drill / bits
- tin snips https://amzn.to/2HctipK
- file (nail file or sandpaper would work too) https://amzn.to/2EUuMD4
**The vinyl decal is used as an etch resist. Basically, anywhere the vinyl is covering will not be affected by the chemical. There are a couple other methods of etch resist. A simple quick and dirty method is to use a Sharpie marker and draw your own design by hand. Another is called the toner transfer method which involves using a laser printer to print the mirrored design onto glossy photo paper. The toner from the printer is then ironed (like ironing clothing) onto your metal plate. The photo paper can be soaked in water to soften/remove it leaving the toner image adhered to the plate. This toner transfer method is what I used for my LED Mini-spotlights instructable.
I made a video of the process. If you'd rather watch that, click here.https://www.youtube.com/watch?v=SDNhsr58Jss
Step 1: Prepare for Etching
Cut a flat section out of a license plate so that it is larger than your decal.
Use some fine grit sandpaper to smooth the surface so the vinyl decal will adhere properly.
If you have transfer tape for your vinyl decal, use it. I did not have any transfer tape and did not want to purchase a whole roll of it for this small decal. So, using what I had on hand, I came up with a solution that was a bit tedious, but worked just fine. I used some Glad Press-n-seal, which is a kitchen wrap that has a low tack pressure activated adhesive. The Press-n-seal is pretty stretchy and flimsy, so to give it a bit of structure, I applied a strip of clear packing tape over the top of the Press-n-seal. To remove the decal from the paper backing, I had to apply firm pressure to the corners of the decal as I was peeling it up to ensure that it was sticking to the Press-n-seal. Once the decal was peeled off the backing, I applied it to the aluminum plate and removed the Press-n-seal. I then used some scrap vinyl and packing tape to cover the outside edges of the aluminum plate.
Step 2: Etching the Plate
I had read somewhere that when etching, you’d get a deeper etch if the surface to be etched was facing down, with some space underneath it. To space the plate off the bottom, I cut some slits in some small pieces of EVA foam and slid them over each corner of the plate. This was then placed face down in a plastic bowl. Ferric chloride was poured into the bowl deep enough for the design to be submerged. The foam feet caused the thing to float, so I used a plastic object* to weigh it down. *Ferric chloride will eat away almost any metal it touches.
I let the plate etch for 40 minutes. It is recommended to agitate the container frequently to keep the fluid moving. I’ve seen some people add bubblers or fluid pumps to keep the fluid moving, but I just let it sit. The longer it’s in the etchant, the deeper the etch will be.
When I pulled it out of the ferric chloride, the etched areas had turned a dark color and felt like they had some scale built up on the surface. I put the plate into a bowl of water and used a nylon bristled brush to gently remove the scale.
Step 3: Final Shaping
I removed the extra vinyl/tape from around the edges and marked where I wanted the mounting holes. I drilled appropriate size holes. I then marked the final size/shape of the badge and cut using some tin snips.*
*Some tin snips are made to either be a right or left cut, meaning the waste material will bend/curl up out of the way of the snips. Be aware of which sides of the snips cause the curl. If you need to cut in a direction that will cause the non-waste side to curl, you can flip the snips over so that the waste will bend down out of the way.
I did some final shaping and edge smoothing using a flat file.
Step 4: Paint & Polish
After making sure the surface was clean and dry, I applied several coats of enamel paint to the etched area, using a hair dryer in between coats (optional). I should have used a light colored primer first, just to give the enamel color a more uniform and brighter appearance.
Once the final coat was dry to the touch, I peeled the vinyl decal off. This left the logo and border a nice aluminum color and the etched area painted.
I used some 2500 grit sandpaper and wet sanded the aluminum face. This surface could be polished up to a mirror finish if desired.
Step 5: Install the Badge
I removed the upper cover from the bandsaw and placed it flat on the table. I used a block of wood underneath the cover to support the area where the badge mounted. I reused the original push rivets and hammered them through the holes in the badge and into the cover. I then reinstalled the upper cover on the bandsaw.
Thanks for checking out my instructable. If you found this helpful or inspiring, I'd appreciate your vote.
If you have any questions or comments, please leave them below. If you make your own custom badge, I'd love to see it.