Great videos Greg there are other ways to do it as well. I use a method similar to this to make PCB boards and it will also work on brass. Not everyone has a UV light I don't so I do it a different way. I use a laser jet printer to print my pattern. because laser jet printers don't use ink this works very well. first I design my PCB and print it onto a magazine cover because magazine covers have a glossy finish this allows the print to come off with some heat. The way a laser jet prints is with toner which has polypropylene plastic in it that is heated inside the printer and is transferred to the paper as liquid plastic essentially, this is outstanding resist for etching. so I print off what I want lay it onto the copper clad sheet and use an home iron to iron the pattern onto the copper, the heat from the iron will melt the plastic and stick it to the copper. once I have it ironed on I put the whole piece in water to soften the paper. once the paper is soft it will peel right off leaving your pattern then you just drop it into ferric chloride and it does its thing.
There is another even easier way a sharpie will resist ferric chloride so if you can color you can etch. first find your pattern or drawing trace it onto your metal with an ultra fine sharpie remove the pattern color between the lines drop it in ferric chloride and watch it do its thing. if your doing brass sheet use packing tape on the back like in your first video.
The Sharpie methode is a great idea, I will test it.
I used the laser printer methode also but due to the heating while transfering the picture the edges are not always razor sharp.
See below items I made with the laser printer methode. These are double sided etsched.
This can happen sometimes with the printer method but more times then not it's the amount if pressure used with ironing down the print. I'm using a HP laser jet I get near perfect prints but sometimes ironing them down can squish out the plastic print and mess up edges I now just float the iron on the surface and all is well. You will also have an easier time figuring out the heat needed that's not to difficult. if you get a spot that isn't nice and clean an ultra fine sharpie can help define the edge
What can I say other then thank you for the videos. I see that a lot of model kits supply these photo etched pieces that makes a model quite unique. Now me being the tight-wad that I am, I'd rather be able to make things rather then purchase them (I guess that is why I am drawn to scratch building). Now that you've supplied me with the necessary tools (video link) I will make my own photo etched pieces. Once again thank you, and please enjoy the holidays close to your family.