Taking a step into the world of photo etching is often seen as quite daunting and tends to be avoided by the regular modeler but it’s not as complex and difficult as you might think…
I too had a similar way of thinking up until recently and I’m very glad I took the leap into making my own etched parts because I’ve discovered just how easy it really is!
Micro-Mark make it very easy to achieve with their complete photo etching kit, it contains all the tools, equipment and materials you’ll need to successfully etch your own highly detailed parts. The only equipment you’ll need in most cases is a computer to draw your designs and a good printer to print onto the clear sheet.
The only issues I ran into as a result of living overseas in Australia is the chemicals cannot be shipped due to their corrosive nature so just be aware that if you’re ordering the kit it may or may not ship with chemicals. There’s no need to worry though because making your own etching and developing fluid is very easy and the chemicals required can be bought from most hardware stores.
The chemicals listed in the instructions are Ferric Chloride for the etching solution and Sodium Hydroxide for the developing solution. Both of these chemicals are available locally in Australia however the Ferric Chloride can become a little costly so I opted to use alternative chemicals that give very similar results.
For the etching solution I used a ratio of 2 parts Hydrogen Peroxide and 1 part Hydrochloric Acid, once mixed together they make quite a strong etching solution. To make the developing solution as well as the photo resist stripper I simply use Washing Soda, when used as the developer I mix a 1% ratio of Washing Soda with water and to make the stripper solution I mix a heaped teaspoon of washing soda into about 150ml of water.
The washing soda is very forgiving when developing and you’re much less likely to accidently strip the exposed photo resist when developing.
Caustic Soda (Sodium Hydroxide) is available at hardware store and can easily be mixed to a 5% solution for developing however there’s a fine line between under developing and over developing when using Sodium Hydroxide so you’ll need to keep a very close eye on the developing progress. With the Washing Soda you have a good 2 to 5 minute for developing so you won’t have a high risk of over developing.
The kit comes with a very detailed set of instructions, the time it takes you to read the instructions from front to back is about how long it will take to complete your etching once you get fluent at the process. I found that once I had read through the instructions once or twice and actually attempted a couple of etches the process is quite straight forward and I didn’t need to use the instructions once I had a good understanding of the steps.
Something else to consider for overseas customers is the power source, the kit comes with a laminator and an air pump that both run of 110v, in Australia our outlet power is 240v so I had to purchase a 240 – 110v transformer. They are not overly expensive and I plan to purchase some power tools from Micro-Mark so the transformer will see uses for other tools as well.
The only limitation that you might run into when using the photo etch system is the size restraints, the maximum size etch with the kit is a 3 inch square due to the size of the supplied laminator, the etching tank and the Perspex used for exposing the metal. For most applications the 3 inch square size is plenty however if plan on doing larger etches you may need to source a larger etching tank and bigger pieces of perspex.
When it comes to etching the metal I discovered that if you have very fine detailed parts you’re better to use a thinner metal like 0.005 inch sheets. When using larger sheets up to 0.015 and 0.02 inches I found there was a lot of undercutting which resulted in losing some of the detail near the tips where the design would come to a point. It won’t stop me from etching the thicker material however I’ll definitely keep this in mind when designing objects to be etched.
When you visit the hobby shop you’ll soon discover how expensive photo etched pieces are! If you have even just a few items to etch the pro etch system will pay for itself before you know it.
I’m extremely impressed with the system and it will get used very regularly in my modeling endeavors. Once you’ve used all the supplies that initially come with the kit you’ll be happy to know that restocking is not expensive at all. The clear sheets go a very long way, once you make a template you can just keep them in a safe place and as long as you look after them they’ll last a very long time and you’ll get many etches out of just a couple of templates.
Disposal of the chemicals isn’t as simple as pouring it down the sink, because the etchant is very corrosive you’ll need to take it to the rubbish tip, just make sure they have an area for chemical waste as not all rubbish tips can accept chemicals. What I do is once I’ve finished with the etchant and I’m ready to dispose of it I’ll pour it into a large 5ltr container, once the container is full which takes many months I’ll then drive it down to the rubbish tip to dispose of it. It’s actually quite a painless process and the environment will thank you for it.
If you decide to give photo etching a go be sure to consider using the Micro-Mark Pro Etch System, it will help you get great results the first time!
If you want to save some money you can use the promo code 'boulder' at the checkout when shopping at Micro-Mark and get 10% of the order.