get it cut out of a sticker from a sign guy it will be cleaner
That would be nice, for sure. But the main idea of the OP's method is that you can do it yourself by using a laser printer. I've done a few homemade t-shirts and signs by hand cutting with an x-acto knife in various things to make templates for silk screening or spray painting designs. Getting a template from a printer would be awesome.
One time I etched in aluminum plate with muriatic acid. I cut the design from some thin wax-like material. It was sold in sheet form - I think it had something to do with canning (like pickles). The cut-out parts were etched by the acid really deep. I was surprised how well it worked.
The same thing might be achieved with the old-school lacquer sheet silk screening material.
Obviously this etching works with a laser printer. I would like to see the results with a solid ink printer.