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Highly detailed ornaments

Etching as such can be extremely powerful technique in modelling and until recently it seemed to me very unrealistic to use it at home. I was very wrong.

Always the need is mother of all inventions… well in that matter I did not invent anything but it pushed me towards research and tests. For my ZENIT I wanted to prepare number of relatively small and accurate items out of brass. To cut it out – forget it, it would ruin thin plate, so the only way was to etch it, but how?

Having searched the internet I have found few posts and articles on etching, and tried to adapt it to my environment. So there are 2 major ways to prepare metal plates for etching: more expensive and more accurate and cheaper and relatively accurate :-) Final etching process it the same. Photo etching requires usage of ultra-violet light and then developing of exposed plates… to complex for home usage in my opinion. So here is the other way which requires only laser printer, foil or glossy paper from magazine.

Preparing the Foil

Printout on the foil

You can create only one side of the plate and then cover second side with paint or you can create mirror image and have two foils, one for each side - this method is a bit more tricky but, gives you more flexibility. Most difficult part is to make sure that foils on both sides are placed correctly and printed elements fit each other. As you see on the picture I printed also small circles around etching area with small dots inside. I will use them for exact pinning later on.

Normally when you print on laser printer, the toner will be on top of the foil or paper. So in case you work with text characters you may have to be printing mirrored image!

Now we have to get the toner from the foil onto metal plate using normal iron. I cut out my printings and cut out piece of copper and created a sandwich out of it where copper was in the middle. Make sure that toner touches copper! Now using normal pins I pinned down both foils making sure they are positioned correctly. Finally I start to press the sandwich with iron for few minutes on both sides. Afterwards I let it cool down.

You should let the plate cool down, otherwise when you remove the foil it can happen that parts of toner that should stay on the plate will still go away with foil (as in my case).

Later on I simply started to peel-off the foil gently, and when I noticed that some toner was still stuck to foil, I immediately stopped and pressed it with iron again. So you repeat pressing until all toner stays on the copper plate.

Now we are coming to final stage, where you get to see results. You can etch with natrium persulphate or ferric III chloride. First one seems to be faster, and is transparent but is more expensive (400g ~ €6 ), and requires temperature of around 45°C for the solution. Otherwise etching will be very slow, or can even not happen evenly. Ferric chloride is cheaper, and less sensitive to temperature but theoretically slower (have not really noticed…) but the colour of the solution is very brown, and very un-transparent. To see the progress you have to pick up the element out of the solution.

I used both solutions to check on results, and honestly still do not have an opinion which one is better. Time will show :-)

After around an hour I started to see clear results! Before you will not see much really. I tried move the plate every 10 minutes to makes sure the solution reaches everywhere :-). And finally I could see my etched parts!!

Note that etching time depends on the thickness of metal plate. So far I tested my stuff with 0.2, 0.3 and 0.5 mm brass and copper plates. Some say that you should not exceed thickness of 0.5mm as material gets over-etched, but I was OK so far.

Of course I was not so good with my first plate, actually I was very disappointed, second attempt though was much more encouraging!

Zenit's funnel