Friday, 30 August 2013

Etcher – Instrument Panel design – Part 2

Well, I’m out of state for a couple of days so I can’t really do anything on the Instrument Panel other than plan and speculate.

Also, I’ve realised that I don’t have the tools in my flat to be able to cut the brass plate, so I have enlisted the help of a mate who has some tools.

I’ll be taking the stock over to my mate early next week and I’ll get the stock cut into the panel that I want and some off-cuts. I’m going to use a piece of the off-cut as the cathode for the etcher. This will just need to be bent so that it hangs over the lip of the salt bath and the negative of the etcher will clip to it.

I still need to think about how the anode will connect to the work piece. I have a couple of options:

  1. Solder a piece of wire onto the back of the work piece and then paint the exposed wire (so it isn’t just corroded away during the etching process);
  2. Leaving a piece of metal extending beyond the piece required for the end resulting piece;
  3. Braze another piece of brass onto the work piece.


Option 1 and 3 are kinda the same, the only differences are material and method of connection. Option 2 would be OK too, but leaves me with more waste.

I think that option 1 is going to be the most practical solution. Soldering on to the back of the work piece will leave a mark on the back, but it is going to be in a place that won’t be seen by anyone (unless the instrument panel is removed). I’m going to use some solid core copper wire for this, it should be reusable, so it won’t be a resource problem.

I’ve seen some baths where the work piece rests in a “cradle”, but I think that this is only really used where the etch is achieve with acid, not electricity. This could work, in theory, but in practice, the point where the work piece is in contact with the cradle it will need to be exposed, and the cradle will need to be exposed to the bath too, so both will be etched. I think that the cradle would need to be replaced periodically and the contact point on the work piece would have to be trimmed of after the etch (so it would have to be additional material on the piece … probably not all that practical.

Well … that’s probably enough talking about it for now. As I can’t really do anything interesting, I’m going to park this article until next week when I am back in the state.


I have handed the brass over to a mate to cut-out for me. I should get it back in a couple of days … not a big job, just other things in the way.

When I get the cut brass back, I’m going to file the edges and make it smooth so that it doesn’t scratch my iron.

Monday, 26 August 2013

Etcher – Instrument Panel design – Part 1

As promised earlier … I am now going to start work on the instrument panel of the Electrolytic Etcher.

In this article, I’m going to go through the design, transfer and then the etch of the instrument panel for my Electrolytic Etcher. I’m going to be using the Electrolytic Etcher that I made in the previous articles about that project to do the etching in this project.

To start with, I measured the top of the project box. This comes in at 13cm x 6.6cm. I’ve taken off 2mm from each side to accommodate the rounded top of the box, so that the plate doesn’t extend over the rounding.

I made a basic design in the previous article so that I could work out where to drill the holes for the various parts of the device.

Now, I want to add some design elements to the panel.

I’ve used Photoshop to do my design work. I also make heavy use of guides in Photoshop.

I scanned the original, hand-drawn layout at 600 pixels per inch. This size means that I have a good resolution to work with. The down side is that it turns out to be a fairly large file (about 17Mb). Still, hard disk space and memory are cheap, right?


You’ll notice that I’ve also left a fairly generous border around the image (Document Size).


Once I had the scanned image, I cleaned up all the messy bit’s from erasing lines. Did some rotation of the image so that it was lined up properly in Photoshop, then I replaced the hand drawn bits with clean lines and layers.


I split the image into:

  • field;
  • border;
  • dial;
  • through holes;
  • labels (individually);
    • Terminals;
    • Power LED;
    • Switch;
    • Numerals;
    • Panel Title.
  • Drill Guide


The above is the field, borders, through holes and dial, all cleaned up.


The numerals around the dial were then placed and I made a new layer under each number with a white circle with a black border. To make the circles, I first created a black filled circle and then contracted the border by 4 pixels and filled it with white. I do this for all of the other labels (except the panel title).


For the Off/On switch, I made the text panel by creating two circles, adding a rectangle and then subtracting the circle in the middle for the drill guide.


For the panel title, I added the text, copied the text layer and rasterized it, selected the rasterized layer and expanded the border by 14 pixels and filled it in black. Then I contracted the border by 4 pixels and filled it with white. Finally, I removed the small holes in the text that were made when I expanded the rasterized text.

Then I started playing with the field. I wanted a pattern in the field that sits behind the text, dial and drill guides.

I started with a black and white leather texture pattern.


I also tried a steam punk black and white repeating pattern.


It’s probably a bit busy …

I’m going to go with the leather texture.

When I transfer the image to the brass plate, the image will be reversed, so I need to reverse the artwork so that it comes out the right way.

First I make a copy of the Photoshop file so that I have a backup. Next, I flatten the visible layers. Then, I flip the image horizontally.


Resulting in …


A mirror image of the panel.

When I etch, the bits that are white will be the bits that are etched … the bit’s that are black will be protected by the toner ink. So I need to invert the colours.


And, you guessed it … it turns out like …



There’s a whole lot less that will be etched (around about 35%), so the etch won’t need to take very long to get a good bite.

Well … that’s the design process done. Next, I’m going to print it out and transfer the image onto the brass.

Sunday, 25 August 2013

Electrolytic Etcher–Design progress–Part 4

This weekend, I fitted the electronics into a project box so that the electrolytic etcher is all packaged up and ready to use.

I also added a LED power indicator into the circuit. After doing some testing, I discovered that my old LED was indeed dead, so I added a brand new LED lamp to the circuit as per the design shown in part 3. The LED doesn’t show up very bright in the photograph … but it is there and it does work.


I am using a 5 amp globe to demonstrate that the power is indeed flowing through the circuit and that the potentiometer does indeed regulate the flow.

The image above shows the project in the box plugged in, but switched off.


Above, the project is switched on, but the potentiometer is dialled to 0%. The lamp is off.

And finally, below, the project is switched on and the pot is dialled to 100%.


You can see that the lamp is now well illuminated, so the available voltage is now flowing through the circuit and to the alligator clips.

I will still be working on this project for a while yet. I still want to make a top panel for the project box with a dial indicator, switch and power labels and positive and negative labels.

I’ve drawn up and scanned the basic design that I will etch into the top panel. I plan to do a bit of tinkering with the design for the top panel yet. But this is what it will look like.


The plate will be etched in brass and I think that a nice copperplate font will be good. I might put a kind of cogs and wheels design into the ground area for interest … I’m not sure yet.

Again, I can’t stress this enough, this is a simple design and has been pretty easy to build and test. I can only estimate the total cost of the project, because I had the power supply, switch, wire and solder already on hand. My out of pocket expense for the project was $14.00, getting the parts from Jay Car. If I had to buy the adapter and the switch, it would probably have increased the cost by about $20. Although, you could do better than that if you sourced your supplies from eBay.

Next, I will start an article on electro-etching using this project as the power source.

Wednesday, 21 August 2013

Electrolytic Etcher–Design progress–Part 3

Well … that was more successful.

The new design without the LED and with the potentiometer wired in correctly … works fine.

Etch Circuit v2

I’ll get around to wiring in the LED at some later stage. For now, the etch controller/driver appears to be wired correctly and is giving me an output voltage. When I get around to getting my test equipment out of storage, I’ll do some voltage testing of the output.


Wire up prototype

Here is the wired solution. SPDT, Potentiometer, banana plugs attached to alligator clips and using a lamp to test the voltage output. I haven’t heated the shrinky on the AC lines yet, because I will need to resolder them into the jiffy box, and adding  the shrinky to the connection at this stage will just be a pain in the arse.

Potentiometer Wiring

Here is the wiring for the Pot. I got the Retro knob from Jaycar.

SPDT Wiring

The SPDT toggle switch came from an old project. I’ve only connected COM and Leg 1. In this configuration, it is a simple On/Off switch.

On_Pot at 60 percentOn_Pot at 100 percent

And here it is turned on. The left image is the lamp when the pot is at about 60%, the right image is at 100%. When the pot is dialled less than 60%, there is little to no light coming from it. I’d say that that is because of the minimum voltage required by the lamp. By the way … having a lamp like this is a good test tool for making sure that you are getting some power.

The next steps for this project are to:

  • Put the circuit in the jiffy box;
  • Make an etched plate for the jiffy box with labels for the dial, power and the two banana plug sockets;
  • Maybe add an LED to indicate power.

Well … apart from that, it’s job done. I’ll be using this driver in later articles showing it in use. The first article will be making the etched plate for the driver! I’m going to do that with a scanned, hand-drawn image, something a little bit steam-punk.

Electrolytic Etcher–Design progress–Part 2

Ok … so thinking about the etcher circuit, and after reading about potentiometers … it seems I’ve made a rookie mistake.

The legs on a potentiometer, when you stand the pot up and face the legs to you are:

  1. ground;
  2. input;
  3. output.

Since my circuit doesn’t need the ground, my previous design had the input and output the wrong way around.

The corrected design is as follows:

Etch Circuit v2

Not much difference from the previous iteration, but important!

Also, I’m going to simplify the design of the prototype, and not bother with the LED. The LED that I was using was an old component that I harvested from a previous project … and I think that it is dead. When I get back to the inclusion of the LED for indicating power, I’ll use a nice fresh new LED, rather than rely on an old and unreliable component.

Tonight, I’ll de-solder the project and rewire it according to this new version of the design.

Tuesday, 20 August 2013

Electrolytic Etcher–Design progress–Part 1

Hmmm … it would appear that my design for the electrolytic etcher is fashizzle.

Etch Circuit

First, I realised that the position of the LED and resistor should be reversed. So I did that. Then I soldered the parts together and gave it some power … bupkiss, nothing, nadda.

I either have a dud component, or my design is flawed. I don’t have my amp meter, so there isn’t much else I can do at the moment.

I’m going to wait until the weekend so that I have access to my other tools, and then I’ll see what I did wrong.

Of course, it could be that I’ve wired the switch incorrectly …

Oh well. This blog is supposed to be about the stuff that I try, and not everything is going to work first time … whatev’s.

Electrolytic Etching–Plans and Musings–Part 2

I’ve drawn up the circuit diagram for the etcher. This is a pretty simple circuit, pretty much all that it is doing is taking a 6.8V AC Adapter power source and running it through a switch and a potentiometer. The switch is there so that the device can be turned off and on, while the potentiometer is there to ramp the power up and down. The LED, as described in the source article (from the NavaChing website), is only there as an indicator that the power is off or on … it is not essential to the circuit. I’ve added a 330Ω resistor to the LED to help protect the component.

Etch Circuit

This design shows the legs of the SPDT and the potentiometer that are wired in. Because we are using AC power, we don’t need the ground leg of the pot. Also, because this is a simple on/off switch, we are connected to leg 1 and common on the SPDT. When the switch is toggled to position 2, the circuit is broken and the power is off.

Depending on my work commitments, I hope to wire this device up tonight. I won’t be fitting it into it’s jiffy box, however … I don’t have a drill that I can use at the moment, so that’ll have to wait for the weekend.

I’ll post another article later with pictures of the wired device.

Monday, 19 August 2013

Electrolytic Etching–Plans and Musings–Part 1

Following on from the previous articles about Acid Etching. Now I am going to do some etching using electricity.

The principals are the same as with acid etching, however, with electrolytic etching, the atoms are separated with electrons, rather than chemicals.

You can use some pretty safe voltages and the mordant is reasonably safe (salty water) so there is far less risk to your person using this method that using toxic chemicals. Safety should still be observed, the process releases gasses. While the gasses that are released are fairly benign, you should still do this in a well ventilated space.

OK. So … the electricity source. My 12V battery charger is nowhere to be had, and I don’t want to buy another one. The solution? Make one.

I still have a large number of old mobile phone power adapters with a power output range of 5V through to 12V. I don’t need anything as powerful as 12V … so I am using an old power adapter (for something … I can’t remember what it was for … a charger for something that I don’t have anymore).

I want to be able to regulate the power, so I’m going to wire it up to a potentiometer. I also want to be able to switch it off … so a SPDT (single pole double throw) switch will do the trick. I have some parts from other electronic projects, so there isn’t much that I need to buy.

The parts list for the power supply are as follows:

  • 6.8V AC Adapter;
  • SPDT toggle switch;
  • 330Ω Resistor;
  • 3mm 5mA Red LED;
  • 10kΩ linear potentiometer;
  • tuning knob;
  • PCB perf board;
  • 2 x banana plug sockets;
  • 2 x alligator clips attached to banana plugs;
  • red and black multi-strand wire;
  • 130 x 68 x 44 mm jiffy box

(the idea for this power supply came from NavaChingEtching, although I have modified the design so suit my purposes … I don’t plan to run the etcher from batteries).

I have some testing and soldering to do first, so I’ll post some pictures later when I get the device working.

As I have mentioned in other posts, I’ve had some success with electrolytic etching steel previously, but this time I want to etch brass so I’ll walk through the process in some detail so that others can benefit from my mistakes.

To recap on the process … design, print, transfer, remove paper from work piece, connect work piece to the positive (+) rail, connect a conductive piece to the negative (-) rail, immerse work piece and conductive piece in salty water, power up, bubbles and etching happen, power off, clean work piece, enjoy your success.

Sunday, 18 August 2013

Acid Etching … musings and plans – Part 3

Tonight, I got around to having another go at the acid etch of my test piece.

If you recall, the last time I did this, the acid wasn’t bighting very deeply in the metal. The process was OK, but the result was rubbish because the acid wasn’t strong enough.

I went and bought some more peroxide and made the acid a little stronger.

01 - transfer

I used a better quality paper (Kodak premium photographic paper this time) and I added some more peroxide to the acid (the peroxide weakens over time with sunlight).

I gave it a good ironing, but the transfer was still missing some bits … so I did it again.

02 - bathe

Then I bathed the piece in water to get the paper off … resulting in …

03 - transferred

A reasonable transfer. There are still some holes in the transfer, but I’m going to go with this anyway. It has a nice distressed appearance.

Next, instead of wiping the acid onto the piece, I immersed the piece in acid for 30 minutes.

After that, I used some acetone to clean the toner from the surface of the piece and gave it a bit of a light polishing.

04 - ascetone

You can see that the acid has bitten more deeply into the surface this time. The overall appearance is quite good, and I am happy with it.

05 - cleaned

As I said earlier, it looks more distressed, and that is a good thing in this case. Of course, I won’t always be looking for a distressed result, so I need to improve my transfer technique so that it does what I want it to do every time.

I’m not really sure what I am going to do with this piece now that I have made it … maybe just cut it out and mount it in a stand … who knows.

Tuesday, 13 August 2013

Steampunk Goggles–Simple Prototype

Goggle Design

For my prototype goggles, I’m going to keep with a pretty simple design. Two eye cups mounted on a nasal loop with a strap that goes around the head. Kind of like old style motorcycle/airman goggles.

The eye cups will be cylindrical pieces with straight sides and a curved outside edge that wraps around the eye. The curved piece will connect to the leather strap that goes around the head. The nasal will be a simple curved piece that will be brazed to the two eye cups, forming a single, unhinged piece.

I have made a cardboard template that fits comfortably on my eye, and from this I made some measurements and then did a design using Gimp.

goggle body

The design is 17.5 cm x 6 cm … I still need to print this out, transfer it to cardboard and then test the design against my face again so that I can make any refinements to the design that I need to, rather than simply go straight to brass.

The design was done using Bezier curves so that the design work is easier than using my compass and protractor … although that’s how I started with the design.

I have also made sure that the image that I am creating in Gimp is 1:1 scale, so that when I print it out, I don’t have to fart around with scale.

I have left a border, top and bottom, so that I can add some border design later on … but for now. That’s the hardest part of the design done.

Friday, 9 August 2013

Electrolytic Etching Steel

Some time ago, I wrote a puff piece about a reproduction 15th century crossbow that I made. One of the things that I mentioned in passing in that  article, was that I electro-etched the metal on the piece to add design and “age” to the finished product.

It’s probably worth exploring the process, since it certainly isn’t hard, but it is a worthwhile technique to know.

Basically, electrolytic etching is a process where you immerse a positively charged piece into a negatively charged solution. The positively charged ions in the metal (anode) are attracted to the negatively charged point (cathode) through a process of oxidisation. Or … put simply, the solution makes the metal rust, the electricity takes the rust away from the metal.

The art in electrolytic etching is in the design and execution of the resist.

To make the crossbow parts, I painted the steel pieces with a black acrylic paint and allowed it to completely dry. Then I drew the design onto the painted piece and scratched the design using an awl. You could just as easily use a nail, pin, fingernail … whatever will remove the paint, exposing the bare metal underneath. I also attached a copper wire to the back of the steel piece to connect to the anode (connected to the positive source).

I made up a saturated saline solution mixing the salt in until the water is saturated (that is, no more salt will mix into the solution).

The piece was then immersed into the solution connected to the positive rail of my power source (a 12V battery charger). The cathode was then immersed into the solution (via another copper wire) and the charger was turned on.

You should see bubbles rising from the exposed metal on the piece … this is from the oxidisation process. Tiny flakes of steel will be coming away from the piece also and going into the solution.

I gave the pieces about 15 minutes in the solution before taking them out.

Next, I used some steel wool and running water to scrub the paint away from the pieces and gave them a good polish.




These “freehand” etchings are quite nice and are satisfactorily “distressed”. There is some pitting that has occurred in the design, but these are entirely suitable for the end result that I was looking for.

An alternative method for producing the design, that I have used successfully with printed circuit boards and which works just as well with electrolytic engraving, is to print the design on a laser printer (onto a gloss or semi-gloss paper) and transfer the design onto the metal using the iron-on transfer method (remember to reverse the design).

To iron the design onto the metal, turn your household iron up to it’s hottest setting, place the paper onto the metal piece (ink side down) and iron it on. This will take up to 4 minutes of pressing and moving your iron around onto the piece. Drop the metal piece into hot water and let it soak for about 15 minutes. Carefully peel the paper off until you are left with just the metal and the toner.

Use acrylic paint to coat the back of the piece and to touch up any bits that are not in the design. Attach your anode and proceed as described earlier.

Paypal Donations

Donations to help me to keep up the lunacy are greatly appreciated, but NOT mandatory.