Friday 25 November 2011
A brass headbadge
Here's a headbadge I knocked up from brass for my next frame.
The process was surprisingly simple. I started with an offcut of 1.6mm brass sheet. I polished the front surface with brasso, then cleaned it thoroughly and coated it in a thin layer of etch resist. I overlaid the black part of the little fish logo printed on clear transparency paper, and exposed the resist with ultraviolet light. Then I developed the resist to remove the unwanted stuff, put some tape across the back to protect the back, and bunged the whole thing in an etchant tank for about 30 minutes.
This setup is usually used to make circuit boards, and etch times are usually about 3-4 minutes.
Once I pulled it out of the etchant and washed the resist off, I had this:
I then rolled it to fit a headtube, cut it out, gave it a quick polish, and hey presto. The etching is remarkably deep. I confess I'm surprised at how well it turned out. It was done as a quick experiment during lunch, and I expected all the lettering to disappear.
All that remains is soldering it to the headtube and infilling the etched areas with colour.