Etching Brass Bullet Pen

[BradG]

I like that system. I will have to give it a try. I have a 12v 4A battery charger that should do the job.

Lower voltage will give you a better result

Interesting, very interesting
Does this process give off any fumes?
I assume good ventilation is essential

Mainly hydrogen.

i wonder if it would work with ali sheet instead of copper. Also I would need to brush up on my drawing skill which are next to a 3 year olds

use stainless. If you use vinyl stickers you will get very crisp results. The secret to using vinyl stickers is to pour boiling water over them once applied which melts the adhesives really bonding it to the surface. it also shrinks it a little helping to remove small bubbles and creases. I found I could skip the boiling water step when electrolytic etching and still get good results, though I could see the masking had a few bubbles under it which could have posed a problem. probably best to continue using the boiling water.

Very essential, using salt produces chlorine gas so make sure you do it outside or with great ventilation.

Peter

Not strictly true Peter. While the anode will release a chlorine ion, sodium hydroxide which is formed at the cathode as a byproduct in the electrolyte, allows to chlorine ion to bond with it, forming sodium hypochlorite, converting it back to a liquid. the oxygen molecules produced will go on to create hydrogen gas. It's also worth mentioning that water alone at room temperature will absorb upto 4 grams of chlorine per litre. if you were to run the tank for one hour at one amp, 1.3grams of chlorine would be made. This should serve as a reminder to change your etching solution regularly so they do not become saturated. This leads on to make sure you dispose of the waste responsibly. you may be able to pour salt water down the drain, but not when it contains a high concentration of metal ions. bottle it and take it to your local council disposal service.

The key to this prevention of chlorine gas is to use an inert Cathode, and the correct amount of salt. The OP is etching a copper based alloy, and is using a copper cathode. as they match no undesired reaction will occur. If you was etching aluminium you would use aluminium cathodes by this logic too. How much gas produced is proportional to the current (amperes) multiplied by time (hours)


Personally, I prefer to use a more universal inert cathode such as stainless steel. I use a stainless cooking pot, with the negative connected directly to its handle, giving me a 360 degree electrode ensuring the etch is even all around. The best way of making the cathodes would be titanium plated in platinum.

 

[Penpal]

Icing on the cake Brad. Thanks Peter.

 

[wm460]

If you use vinyl stickers you will get very crisp results. The secret to using vinyl stickers

When you say vinyl stickers, is insulation tape or duct tape OK?

Personally, I prefer to use a more universal inert cathode such as stainless steel. I use a stainless cooking pot, with the negative connected directly to its handle, giving me a 360 degree electrode ensuring the etch is even all around.

Do you have to put some thing between the shell case and the saucepan?

 

[BradG]

insulation & duct tape would work fine, but I mention vinyl stickers because they are cut out on a vinyl plotter/cutter which is similar to a printer. This will give you a cut out pattern which can be applied which gives you sharp edges to your etches, oppose to wobbly lines and rough finishes by using other masks.

I personally don't put anything between the anode and cathode because I use a jig which would prevent me from being able to accidentally touch the two together (arc welding is beyond the scope of this post ;) ) of course if you wanted to take a precautionary measure with that, go to the garden centre and buy a net pot large enough to fill most the pan and submerge it. this will act as a barrier nicely.

 

[Phil Dart]

Crystal clear and concise Firefrode. You and Brad have de-bunked a great mystery for me. Two quick questions Firefrode please... firstly, where you attach the croc clip to the anode, will that not leave a mark after etching, and will it not itself become etched? And secondly, to what sort of depth is the resultant etching using your parameters. In other words, how much could you polish the anode before wearing off the etching?

 

[Penpal]

Detail is beaut following this with great pleasure my best vision of how to use shells I have yet seen that covers my design for these pens.

Peter.